type : achromatic doubled refractor
clear aperture : 40mm (1.6")
focal length : 800mm (f/20)
eyepieces : 0.965" fully coated 25mm and 8mm Kellner's (Japan)
finder : 5x25mm plastic
mount : wooden non adjustable alt-az
This was my first telescope and I still have it today for sentimental reasons. It was with this gift from a friend of my fathers that I saw the rings of Saturn for the first time!! By today's beginner scope standards it is a very crude scope. It does have an achromatic glass objective lens that appears fully coated and comes with good fully coated 0.965" Japanese made Kellner eyepieces of 25mm and 8mm focal length (much better than the current crop of 0.965" Chinese made H, HM and SR eyepieces!!!). The package also includes a prism star diagonal which is judged to be inferior to the mirror diagonals. Since it has a focal length of 800mm, that gives me 32x and 100x magnification. Chromatic aberration is non existent due to its extremely long focal length and, if I remember correctly, it gave very good star test patterns. The tripod is an extremely shaky wooden tripod that is non adjustable in height and does not come with an accessory tray. The mount head and finder bracket is metal but everything else is plastic. It has a plastic orange colored tube (hip color for that time??), a plastic 5x25 finder (horrible color correction and has its aperture stoppered down) with a metal finder bracket, plastic focuser and focusing knobs and a plastic encased mirror star diagonal.
It was with this scope that I took my first "baby" steps in astronomy. Brighter nebulae and open clusters were easy. I remember the fine views I got of M42, the Orion Nebula and M8, the Lagoon Nebula or M6 and M7. Try as I might, I could never find the M57, the Ring Nebula in Lyra. Most of the globulars I saw as a youth (Omega Centauri, M22) were mere dim grey fuzzballs with no decernible structure. Galaxy observing was almost non existant with this small scope. The only galaxy I saw through this was M31. In fact I had better views of extended objects through my father's 20x50 binoculars! But this scope provided pretty views of the moon and planets. Saturn showed its rings and one moon (Titan). I spent a good amount of time on Jupiter tracking the march of its 4 moons and the two equatorial bands. Mars at opposition yielded polar ice caps and Syris Major! And I spotted Halley's Comet from the rooftop of my parents home and followed it for months. Halley's spotted a fan shaped tail and some jets! This scope has also seen Comet Hyakutake! All in all, it was an OK scope. I would never recommend anyone to start with such a small scope, but with this scope, I honed my observing skills in star hopping (with the insufferable excuse for a finder) and averted vision.
3"f/9.2 Newtonian alt-az reflector (sold)
type : newtonian reflector, spherical mirror
clear aperture : 76mm (3")
focal length : 700mm (f/9.2)
central obstruction : 19.9mm (0.26%)
eyepieces : 0.965" H20mm, H12.5mm and SR4mm
other included accessories : 2x plastic barlow and 1.5x erector lens
finder : 5x25mm plastic
mount : wooden adjustable alt-az with micro control for altitude and accessory tray
This was my first real scope that I purchased with my own hard earned money. Got this in June 2001 when I got back to Brisbane, from a good shopkeeper David at the then called Leisuretronics (now renamed Gamestronics). Quite a good scope for the money and it has enough light gathering power to view some objects with a little bit of detail (see "about the author" for details). The navy blue optical tube assemble (OTA) is made up of sheet metal (with crinkled textured metal end rings) and it has a metal 1.25" rack and pinion focuser with plastic focusing knobs. The focuser itself is quite good with little backlash. That and the fact that you can adjust the tension by simply tightening the two screws that hold the rack to the pinion. One thing to note though is the extremely limited focus travel of the focuser. Using a Meade Shorty 2x Barlow, I could not get images to focus. It comes with a screw on 0.965" adaptor, which I judged as an inconvenience and pathetic 0.965" eyepieces (H20, H12.5 and SR4). Out of the three only two were useable, the H20 (which I used most of the time) and the H12.5. Nothing would come to focus in the SR4. Using 1.25" plossl eyepieces in this scope brought viewing to a whole new different level. The star test revealed minor astigmatism but images were still sharp at 117x. Collimation of the scope is possible with the collimation screws at the back of the scope on the primary mirror mount and the collimation screws on the three vane spider holding the secondary mirror. All require a Philip's head screwdriver.
This scope comes with an equally pathetic 5x25 plastic finder that has been stoppered down, rendering it virtually useless for anything other than bright objects; a 2x plastic barlow with uncoated lens and a 1.5x erector lens with equally pathetic plastic body and lens. It comes with a pretty decent mount (wooden adjustable legs) with an accessory tray. The one thing I did not like about the mount was the micro altitude adjustment knob. There was too much play in that. Overall I think it was quite a good scope if you throw away the eyepieces, the poor excuse for a barlow and erector lens and finder and replace them with some 1.25" eyepieces and a no power pointing device (or even a good 6x30 finder). I think this would be a much better beginner scope than those ubiquitous 60mm refractors out there as from memory I saw better detail in the planets (Cassini's division in Saturn and ruffling in Jupiter's equatorial bands), much more nebulosity in the brighter messier nebulae (finally found and saw the ring shaped M57 and the apple core of M27), galaxies (NGC 253 immediately comes to mind!).
6"f/9.3/SPC6 6"f/5 Optical Tube Assembly Newtonian equatorial reflector
type : newtonian reflector, spherical mirror with corrector lens in focuser (replaced with SPC6 OTA parabolic mirror)
clear aperture : 150mm (6")
focal length : 1400mm (f/9.3)/750mm (f/5)
central obstruction : 1.6" (0.27%)
eyepieces : 1.25" 25mm, 9mm and 6mm Kellner's
finder : 6x30mm achromatic fully coated
mount : equatorial mount with slow motion control and accessory tray
My first serious scope and probably my main scope for many years to come (until I exhaust its capabilities). This scope came courtesy of my better half (thanks Siok Hwee). It comes from the same manufacturing plant in Taiwan (Lin Optics) as my previous scope and it is a pretty decent scope for the money. Had some problems with severe astigmatism (even after collimation...which by the way is very, very difficult due to the presence of the corrector lens in the focuser) and had to get the OTA changed. I was fortunate as the shopkeeper at Gamestronics (David) was very helpful. The new OTA was heaps better and came almost perfectly collimated. My first choice was actually a 6" dob (and many times I though I should have just gone with that.....but I can only get them through mail order....). Anyway this one works better from my apartment balcony anyway.
The main OTA is navy blue in color and it is made up of the same sheet metal as my previous scope. The rack and pinion focuser is 1.25" in diameter and is an all metal assembly with the exception of the focusing knobs which are plastic (they are bigger in diameter than the one that came with the 3"). The focuser is just as smooth and free of backlash as the one on the 3", plus it appears sturdier and even has a built in T adaptor that accepts normal SLR cameras. Just as the previous focuser, tension can be adjusted to suit the individual. The eyepieces that came with this scope was a class above those that came with the 3". All seemed to be fully coated and gave reasonable views. All also had decent 50 degree field of views but no rubber eye guard's. I used the 25mm most of the time (56x) and the 9mm (156x) on occasions. The 6mm stayed in the eyepiece box for most of the time as I found that the scope could not handle magnifications above 200x without image breakdown (even 156x was pushing it). This was probably due to the spherical mirror and possibly the corrector lens. Star test revealed astigmatism and curvature of field. Surprisingly I had no problems with chromatic aberration on brighter objects, although the scope had an auxiliary achromatic corrector lens in the focuser (appears to be fully coated as well). The views were dramatically improved when I substituted the Kellner's with a 32mm, 20mm, 12.5mm Plossl and a 9mm Synta Ultrawide (superwide is more like it at 66 degrees field of view). All have better contrast (well the Ultrawide has a slightly lower contrast than the Plossl's), and are sharper all the way to the edge of the field. Coupled with a Lumicon UHC, the views of nebular objects were incredible. The Orion Skyglow suffered lack of use as a result. The UHC was just so much better....anyway back to the topic.
The finder is a vast improvement over the pathetic excuse for a finder in the 3". While at times I wished I had a bigger 50mm finder, it is sufficient for the moment. It has an achromatic fully coated objective lens, a plastic body, an adequate dew shield (much better than those that come with the York Optical scopes with their super short dew shields). Eye relieve is adequate for spectacle users. The finder bracket is a six screw plastic deal and while very hard to align, it holds the alignment very well. My only gripe is that it does not grip on very tightly to the scopes OTA and gets knocked out of alignment pretty easily. Also its pretty hard to see the crosshairs when observing under very dark skies.
The mount itself is a pretty decent. No plastics here. While by no means the sturdiest mount (the NES mounts on the York Optical scopes are way better....these are the equivalent of Orion's Sky View Deluxe mounts….or maybe better), it is up to task for this super portable 6". Damping time at high magnification (150x and above is about 5 to 6 seconds on my concrete apartment balcony). I reckon that the damping time could be further reduced by replacing the stamped aluminium legs with wooden legs or maybe by getting one of the new shock absorbers for tripods from Orion. It does not come equip to take a polar alignment scope but it does have slow motion controls for right ascension (RA) and Declination (Dec). These are flexi cabled motion controls. The Dec flexi cable is conveniently placed and I use this most of the time for tracking objects (when not in equatorial mode...I only bother to polar align when doing planetary high powered observations which is seldom). The RA flexi cable are at inconvenient positions most of the time. This scope also comes with rotatable tube rings and those Vixen inspired quick release mounting heads. You can simply slip the OTA with the tube rings on and off the equatorial head on a whim. Adjusting the altitude is easy with the L shaped screws on both sides of the mounting head.
Collimation is achieved by a push pull mechanism on the primary mirror cell and the secondary mirror's three vane (which is way thicker than the ones on the 3") spider using a Philip head screwdriver. If you ask me, I think the need for a Philip's head screwdriver is inconvenient. The design of the primary mirror cell seems to be a copy of the Vixen mirror cell. Therein lies the disadvantage. This mirror cell is very crude and does not have springs. For each set of screws, one tightenes to hold the collimation and the other is to allow for the mirro to be tilted ever so slightly. The mirror mount on the SPC6 seems to be identical to this. I noted that with these type of mirror cells, it is better to not overtighten the screws as this will lead to astigmatism and distortion of the mirror's figure.
Overall it is a good scope. My only gripe with it is its inability to handle high magnifications (6" are capable of magnifications in the 200-300x range) which is probably the direct result of its optical configuration. The scope works best below 100x but can be pushed a little more to about 156x. just make sure the collimation screws are not tightened down too much. Also contrast on planetary subjects suffer due to the bigger central obstruction on such a short focal length. That and the fact that off axis aberrations are more pronounced too. A long focal length parabolic mirror would probably solve all the problems listed above. Also instead of flexi cable slow mo controls, they could just supply slow mo knobs.
NOTE: The optical tube assembly has recently been replaced with a SPC6 OTA. This comes with a parabolic mirror and has a focal length of 750mm (f/5). Made by Vixen in Japan for Celestron, I can now routinely use mags of up to its theoretical limit of 50x per square inch. Images are way sharper and stars focus down to a point now. Images also seem a little bit brighter probably due to the enhanced coatings on the mirrors. Globulars like Omega Centauri (resolved even at 46x), M13, M4 and M13 all show nice resolution with the chains of stars effect at 250x. Jupiter now focuses down to a nice color free ball and shows all manner of swirls in the equatorial belts. And coma is surprisingly minimal in this OTA. I am also very surprised at how little the contrast is affected by the rather large central obstruction (about the same size as the other OTA). Also I am surprised by how solid the single vane spider holds the secondary mirror. The only problem with this is that it is pretty thick and the difraction spikes (three now) look more obvious then the ones generated by the three vane spider). My only gripe is the sliding focuser (I much prefer rack and pinion focusers) which does not focus very smoothly and the mirror cell which seems to be similar to the previous OTA. The OTA is excellent. Read my recent e mail to two of my observing buddies...
Observing notes: Did you get out over the weekend? Got out at close to 12am on Sat and went to sleep at about 3am. Got some good looks at the milky way and some of the globs in Sagittarius and Ophiuchus. Again the SPC6 continues to amaze me with its contrast and clarity. M10 in Ophiuchus was resolved to the core (dare say better than M13??). The bloody tree was obscuring the other messier near M10 (M12?) but I am sure that would have resolved as well.
M22 was a stunner. The outstretched arms were very prominenet at 47x (infact they looked better at low power because at 166x and 250x I was looking more at the core and the stars had gaps between them {much like Omega Centauri and how it looks better at 47x}). The glob looked decidedly lopsided as the arms were to one side. M11 the wild duck cluster was nothing like an arrowhead at 166x. Very nice cluster.
Also looked at M8, M20 and M17. M8 looked amazing at 23x. Tons of extra nebulosity surrounding the core nebulosity. M20, the Trifid's dark lanes were more pronounced in this scope (probably due to its sharpness again) at 47x. M17 did not just show the swan at 23x, but extra swirls of faint nebulosity surrounding it (all these observations with the UHC of course). The back of the swan looked distinctly feathery at 47x. Then there is 6302, the bug nebula. Very nice views at 166x with the faint "extensions" to the right and left of the brilliant bright central region. And as if that was not enought, I finally saw 6337 (supposedly difficult 13 mag planetary...did not manage to see it in the older "spherical" scope) as a faint and small ring (with the UHC) in Scorpius. This one is also very easy to find as it is close to the bug nebula. And to top things off, I saw the ghostly Veil Nebula (the portion around 52 Cygni). Very ghostly but definately there with tapping and averted vision.
p/s: this scope has also made me a moon fan. Detail just seem to jump out at you at 166x. Seeing has been dreadful so I am pretty much limited to 166x and below. Again the surface looks like a marbled texture...
15x70 Saxon mini giants (SOLD)
My quick grab and go scope (or binoculars), these babies replaced my 3" alt-az Newtonian and my 10x50 binoculars. They are great as grab and go's as they are light enough to be hand held (approximately 2lb) and have sufficient aperture (compared side by side with Andrew's 4" ST and they had nearly the same light throughput!) for some really great wide field views. Observing with large binoculars is an experience by itself. Words just cannot describe the feeling of scanning the heavens with both eyes and coming across numerous celestial puff balls. Enough said. This was a deal too good to refuse!
The binoculars itself is encased in a nice rubber armour (not leatherette like in normal binoculars) and has a central focus wheel (which is very tight so it holds the focus very well) and a tripod mounting head. The straps that came with the binoculars (1/2 inch???) left much to be desired and digged into my flesh as I used them. I had them replaced with 1 1/4 inch video camera straps. The objectives and the eyepieces are all fully coated with a nice bluish sheen. The eye cups are huge and can hold mounted nebular filters. The field of view is vast and eye relieve is so good that you sometimes get blackout problems. The prisms were advertised as Bak4 prisms and I had them checked out and they were Bak4 prisms (no diamond shapes exit pupils at arms length). The views are surprisingly crisp and sharp to about 80% out of the field of view.
Now for the gripes. After mounting these on a tripod I noticed that the left objective seemed to have a little bit of spiking. These may be a little bit out of collimation. Also since the focus wheel is so tight, I sometimes have problems trying to focus. That and plus the fact that the focus wheel is pretty smooth (not the usual focus wheels with tiny teeth). Also the binoculars only came with a soft carry case :(
For observations this binoculars has continued to amaze me. It was with these that I bagged some objects which I deemed impossible from my suburban balcony. Caught large face on spirals M83 and M33 easily (could never find them from suburbia in my 10x50’s, 3” or 6”). Other objects included M57 and 2393 (seen as fuzzy stars), M1, M65 and M66 (surprisingly easy…..will train them on the Virgo cluster when they get higher). Open clusters and large extended nebulae are seen to advantage. While never intended for planetary observations, I tried them on the moon, Jupiter and Saturn. Surprisingly chromatic aberration was not as distracting as I expected. The moon very sharp and contrasty and looked quite clean with only slight purplish tinges seen. On planets I managed Titan, Saturn’s largest moon and Saturn’s rings (can be seen!). Jupiter’s two equatorial bands were hinted and the four moons were easy. The problem with the planets was that they never seemed to come down to a sharp focus. Just when you think you have them focused, there seems to be some spiking. Oh well….
A very good deal and I think this is the ideal quick look scope for me. Almost no setup time and no cool down time. I can just grab my trusty camping chair and an observing guide and I am good to go. Perfect!
Orion Short Tube 80 f/5 optical tube assembly (second hand)
type : air spaced achromatic doublet refractor (multi-coated)
clear aperture : 80mm (3.1")
focal length : 400mm (f/5)
eyepieces : none
other included accessories : mounting plate and StellarVue enhanced 1.25” diagonal
finder : 6x26mm Orion correct-image metal finder on dovetail bracket
mount : none
After using the 15x70’s for about a year, I began to miss my lightweight 3”newt and its easy setup for those casual nights of stargazing when I just did not feel like lugging around my 17-18kg EQ newt. I also yearned for a more diverse range of magnifications. Take nothing away from the binocs as they will always be my ultimate grab and go and airline travel scope. I just wanted something that will allow me the luxury of more magnification every now and then. I wanted sharp contrasty views only a refractor could give. I also wanted to stay within my budget and hence my search on Astromart. After looking around for a while, I found a suitable Synta made Orion (USA) 80mm short tube (ST). There are several 80ST incarnations current being sold but they are all dodgy (clones of the original Synta made ST), save the original Synta optical tube assembly (OTA). This one garnered excellent reviews in its category of cheap but good scopes. It had respectable optics (can’t say it’s the best since its not an APO or semi-APO scope and never claimed to be one) and every part was made of metal save the focuser knobs. This was one of the drawing cards for this OTA for me anyway. Although its not one of the more expensive scopes around, it just felt so solidly constructed. When I first opened the box, I was struck by how nice the scope looked. It also had a quality feel to it. I was also elated to see that the main objective was fully multi-coated and not just fully coated as Orion stated on their web site.
The first night I got the scope (it came in time for my birthday which was nice) the skies were unusually clear, so I gave it a test run. As it did not come with a mount, I mounted it on my Optex T-560 photo tripod, the tripod that usually sees use with the 15x70’s. While not a Manfrotto, it serves its purpose for the time being. When I put everything on, including the star diagonal, the 6x26 finder and the 32mm Plossl, I immediately realized that, when pointed near zenith, the scope had to be balanced. So I grabbed one of my dumbbell weights and used that as a counter balance (see pics). I have since been able to get it out on several other occasions including a shootout with my buddy Andrew’s 4”ST (also made by Synta). The 80ST held its own against its bigger brother. So what do I think of the scope after having owned it for a good three weeks now? Well all I can say is that it performs as I had expected it to be, after some minor tweaking. When I got the scope, the optics seemed to be pinched (stars did not focus down to a point but were rather triangular in shape). This was easily remedied by removing the dew cap, loosening the plastic retaining ring, keeping the scope upright and then tapping the tube gently to allow the objective to sit nicely in the cell and then tightening the retainer ring to finger tight. Also when looking down the barrel of the OTA, I was immediately struck by how “shiny” the inner tube was (much like how my 6” newt was before I flocked the upper tube). But it did have a single baffle midway down the OTA. I once again unscrewed the retainer ring, removed the objective doublet, blackened the frosted lens edges of the objective lens and flocked the upper tube (up until where the single baffle sits). Now when looking down the barrel, the OTA is pretty dark save the focuser and its three shiny screws (a job for another time perhaps). Even then its nowhere near as shiny as it originally was. A second Synta 80ST OTA (this one was a blue SkyWatcher) which mistakenly made its way to me looked markedly brighter down the tube without the mods I made.
These mods made a whole world of difference under the stars. Views I got of M42 were contrastier, even without the UHC in place. Eta Carina Nebula was magnificient, partly due to the huge FOV (well incomparison to my newt). With the UHC in, I could probably spend hours lost in its many dark lanes, rifts and tendrils. Stars focused down to a point and there were definitely more stars resolved across 47 Tuc’s face then before (same effect I got when I flocked my newt!). Also there was surprisingly very little chromatic aberration in this fast achromat. Sure the views were not as true colored as the views I got in my newt (Saturn and the moon looked a little more yellowish) but they were not as bad as I though they would be. And true to its configuration, the views were sharper and more contrasty than the newt. Saturn was a revelation, even at 66x. Cassini’s division was easy even at that magnification and looked even better at 133x. The difference in color between ring A and ring B was also very evident, as was the cloud band on the disc and the darkened poles. I could even make out the crepe ring (though not as easy as in the newt). Jupiter was not as contrasty or as sharp as Saturn. My guess is because it is much brighter than Saturn. In any case, it was sharper than my newt and showed the two main equatorial belts with two thinner bands (I have to date seen up to 5 bands during a night of excellent seeing with some detail in the one of the main equatorial bands). I have yet to get a very good view of Jupiter but my guess is that I will be able to make out some smaller details on the face. More on this later. Also the trapezium in M42 revealed a very faint, but definitely present e component (much better seen in Andrew’s 4”ST). One thing to note however was that the 15x70 still gave a much better images of extended objects. There was more nebulosity seen in M42 through the binocs than in the 80ST (without the UHC though).
The accessories it came with were also respectable. The Orion 6x26 correct-image finder was nice and solidly built. It was all metal, maybe save the eyepiece portion and the metal bracket was great as well. Lenses were all glass and fully coated with a nice bluish sheen to it. It gives correct-image views and I just simply love the “no brainer” finder bracket..my only gripe it that the views are markedly dimmer than my 6x30mm finder on the 6” EQ. The StellarVue enhanced diagonal was great as well. Felt pretty solid and came with a nylon tip to prevent scarring of the eyepiece barrel, a nice touch. It is claimed that the enhanced diagonal reflects more light than the standard, almost 10% more. Have not been able to confirm this yet though. More testing required. My gripe with this diagonal is that it does not have a recessed ring to prevent it from slipping out of the focuser tube when fully loaded with a Barlow and heavy eyepiece. I also have a gripe with the focuser tube as 1 thumbscrew was not sufficient to hold the diagonal tight enough. I had several heartstopping moments when the diagonal just turned on its own and almost dumped my eyepieces onto the concrete! Also the focuser was nowhere near as smooth as the one on my newt!
102 f/5 4” Synta short tube refractor (SOLD)
type : air spaced achromatic doublet refractor (multi-coated)
clear aperture : 102mm (4")
focal length : 500mm (f/5)
eyepieces : none
other included accessories : mounting rings
finder : none
mount : none
I got this OTA used from a fellow local astronomer with tube rings and a dovetail (EQ5) for a good price. This OTA did not come with a finder or star diagonal. For that I use the finder from my Orion 80ST and the StellarVue enhanced diagonal I got with my used Orion 80ST. The reason’s for its purchase was to supplement an intermediate aperture that could substitute for my C6 newt on trips where the OTA had to ride at the back and risk losing collimation. A refractor can simply be chucked in the boot with some bubble wrap and would not need collimation on arrival. Also this scope could be mated to my existing EQ3 clone mount with an extra dovetail and can be used alt-az without counterweights making it grab and go. Due to the lightweight OTA, this setup was pretty solid when in use. Initial inspection of the OTA revealed a nice and evenly multi coated objective lens. The level of coating was similar to the one on my Orion 80ST. Also there were two knife edged baffles down the tube contributing to the contrast of the final image. The scope has a nice black color. This scope also has a nice 2” rack and pinion focuser that is a bit stiff, probably due to the Synta glue/grease they use for lubrication. Under the stars the scope performed rather well, although the views were not as deep as I liked. There wasn’t much of a difference in views of the brighter globs between my “old faithful” Orion 80ST. There was slightly more resolution in the 4” although not enough to warrant a new scope to replace my venerable 80ST. Maybe I have been spoilt by views in my used Celestron/Vixen 6” which resolves the major southern globs to the core, creating that grain of salt on black velvet effect. Also this scope exhibited markedly more chromatic abberation (and possible spherical abberation as well as the views at higher powers were just not up to mark) than the Orion 80ST, to the extent that I did not like to use magnifications above 100x (my Orion 80ST can be pushed to 133x). I haven’t extensively tested the scope on the major planets but I was not impressed by the views of Mars this opposition. So the verdict….I might still keep this scope for more testing to see if it is worth keeping (it also looks very nice mounted on the EQ J I still find that I use my C6 and Orion 80ST more extensively from home as the C6 gives much brighter and deeper views and the Orion 80ST is just such a sweet setup on my photo tripod. The 4” cannot be used on the photo tripod as the OTA is two times heavier than the 80ST and makes for a very unstable setup.
10"f/5 Guan Sheng Dobsonian reflector (250mm)
type : newtonian reflector, parabolic mirror
clear aperture : 250mm (3")
focal length : 1250mm (f/5)
central obstruction : 25% (approximately)
eyepieces : 1.25" 26mm FMC GS Plossl and 9mm FMC GS Plossl
other included accessories : free binoculars 10x30 and generic moon filter (green)
finder : 8x50mm (nice spring loaded)
mount : dobsonian mount
My first foray into large scope country. I had planned to get this scope in the near future but did not expect to get it so soon. Due to a stroke of luck, my research poster won me some money at a recent BioNano conference for my work on resilin and hence this scope. I have had experience with such a scope as my close observing buddy David has one and I have used it rather extensively from SAS's dark sky site out at Leyburn. My first look through a large scope when I first came back to oz was through a 10" GS dob. I remember fondly the views I had of 47 Tucana, the brilliant southern globular, which was fully resolved into a rich swarm of stars all the way down to the core, and this from a suburban Brisbane site close to the city! From dark skies, some of the component stars actually show color as well. Also the views of Jupiter's belts (too numerous to count) and all the festoons and detail and Saturn's belts and rings (A, B, C components all easy as was Cassini's Division and Encke Minima). I have even seen filamentous detail in M1 the Crab Nebula in Taurus from Leyburn and have sketched several objects through his scope. But this is getting ahead of myself. Now to the very beginning.
I had known all along from the first time I used David's scope that a 10" f/5 solid tube dob would be the scope of scopes for me. It has sufficient aperture to go deep into Abell and Hickson's territory and yet portable enough to fit in a small car without the tube being converted to a Truss. Also the weight of the OTA and mount is not overwhelmingly heavy and one person can easily carry and set up the whole scope in two sittings. Also a 10 inch scope collects 56% more light than an 8 inch scope and a 10 inch has been said to be the smallest of the great dobs. So it was a logical choice for a visual astronomer like me. The die was cast and the order placed on the 19th of December, 2005 from Andrew's Communication down in NSW. The scope arrived at my doorstep 2 days later in two boxes, one housing the OTA and the other flat box housing the mount. When the courier called me at the office to inform me that the package had been delivered, I rushed home to get the boxes into the house. I was surprised to find that the smaller flat box containing the mount to be as heavy if not heavier than the box housing the OTA. Without further ado I began to open the boxes and lo and behold...a nice noble white shining tube....a dob to call my own! I then began to try and carefully unpack the various parts without damaging the contents in my highly excitable state of mind. I made a mental checklist of the various parts that came with the dob, the nice spring loaded 8x50mm dovetail finder, the two 1.25" GS FMC (yes fully multicoated...NICE!) in 26mm and 9mm focal lengths, the free generic green moon filter and the 10x30 roof prism binoculars. When I finally spied the instruction leaflet, I found it to be totally inadequate and spartan. All that was provided was a very small diagram detailing the parts and where they went. The printing was so small that one could not distinguish one screw part from the other. But using my knowledge of the scope, I managed to get everything assembled in about 20 minutes (maybe faster I was not timing myself). Everything to aid in the assembly was provided excluding a Philip's head screwdriver. An allen wrench was provided and most of the screws worked with this. Throughout all these steps, I was meticulously taking pictures as well. So I guess one could put the scope together much quicker. When the scope was assembled, I proceeded to check the collimation. It was nice to note that a center doughnut was present, saving one the frustrations of having to self center spot the primary mirror (which involves removing the primary mirror mount from the tube...not something for the faint of heart). Collimation was pretty spot on and I especially like the finger collimatable collimating knobs and tightening screws.
Surprisingly the weather remained clear for a week and a half after the dob arrived. The weather gods must have been on holidays too. Turns out that I got the dob at just the right time as I had heaps of opportunities to test it out under Brisbane's suburban skies. During summer the limiting magnitude does not penetrate as deeply as the transparent winter skies. I estimated the magnitude limit from my courtyard to be approximately 5.3-5.4. As my current ground level courtyard (the scope will be too cumbersome to carry up and down flights of stairs but it should be doable) only gives access to stars at zenith and near zenith, stars to the south where all the celestial goodies are, and to the north are inaccessible. I made do with M42, the Orion Nebula and the surrounds. M42 was magnificient in this scope. The added aperture made the wings stand out beautifully and I found myself mesmerised by the views even without the aid of a filter. The trap easily stood out at medium magnifications and the E and F component were ridiculously easy. Also at higher power, the cirrus cloud effect became very pronounced in M42. I also looked at M78, the reflection nebula in Orion. This one was easy as well although the views were washed out due to light pollution. The DGM Optic VHT filter made it stand out better. I also looked at the globular in Lepus and this was also resolved at higher magnification. I then surfed around and looked at open clusters (i.e M41, etc.) in Canis Major and checked out NGC 2438 in M46. Its amazing how much power you can use on such large an aperture without the image dimming. 2438 looked like a fainter version of M57, the Ring Nebula at 208x.
Then at the end of the week I had a chance to try out the dob on the whole sky from Andrew's place at Parkinson's, and to pit the dob against a larger scope, namely Andrew's incredible 12.5" f/6 Truss dob. This would also give me a chance to try to fit the dob in my Hyundai Excel Sprint. Fits in nicely once I remove the back cover and put down one of the top of the back seats :) I was again reminded of how easy it was to move the dob. It was not heavy at all. On getting there, we checked out all the usual suspects. The standouts were 47 Tucana (brilliantly resolved to the core with diamonds on black velvety effect...even at low magnifications), M42 again (rusty colors were visible in the wings and we confirmed this in Andrew's scope as well!), planetaries and their inner detail shone through with Andrew's newly acquired OIII filter (NGC 2392, the Eskimo Nebula showed its triangular face and fur parka; NGC 3242, the Ghost of Jupiter showed clearly its CBS eye detail and NGC 2438 showed its ghostly ring visage), the delicate swirls of the Tarantula Nebula with and without filters and its surrounds (its great to be able to surf around without worrying about lock knobs as on my EQ mount...look at all that nebulosity around the Tarantula) and not forgetting Eta Carina and all those dust lanes....goodness! Then there was Saturn. There were so many moons hovering around Saturn and Saturn itself presented so much detail. The banding on the planet stood out vividly as did the pole darkenings. No more subdued shades! The rings showed abundant detail from Cassini's Division going all round the planet to the delicate Crepe Ring and Encke Minima. If I had to summarise the scope in two words, it would be BRILLIANTLY BREATHTAKING. Oh and did I mention that the 10" held its own against larger competition? All the detail that was present in Andrew's scope was also present in mine. Star test revealed a very well figured primary mirror. Patterns on both sides of focus showed similar patterns reminiscent of the excellent mirror in my Celestron/Vixen C6. If there were any gripes, it would have to be the very tight tension springs and the lack of smoothness in the azimuth bearings, but these can be easily remedied using milk jug washers or some ezy sliders.
AOE 20x80LW
My latest aquisition. These are the perfect foil for my large dob under dark skies :) Looking at the price of these giants, it is amazing what little money can buy you these days in terms of optical equipment. This is indeed the golden age of stargazing! Large astronomical binoculars can be had for the price of a single 50mm branded binoculars, with all the bells and whistles. This Aquila Optics binoculars boast fully broadband multicoated optics on all surfaces (as opposed to fully coated optics on my old Saxon's), inclusive of the internal Bak 4 prisms (and it shows when you look down the barrel with minimal green reflections and has no light cutoff in comparison to the lesser Bk 7 prisms that are used on cheaper imported binocs...no diamond shaped exit pupils here) and is very nicely baffled. It has the standard binocular tripod adapter socket and comes with a very nice metal tripod adaptor (as opposed to the tough but still not too rigid plastic one that came with the Saxon's. This one used to flex quite a bit under the Saxon's weight). The focusing mechanism is not too tight and the binocs comes covered in a nice rubberised armor coating (no leatherette here but I am not complaining). The lens caps that came with the binocs were also an upgrade as well as they were nice flexible caps that were really rubbery, thus holding on better than the stiffer caps. The eyepiece caps had a flexible "bridge" holding both of the caps together. There was also a cool carry bag to carry the binoculars in (although I would have prefered a stiffer carry case). The neck strap that came with it was also better than the ones that came with the Saxon's as it was a lot wider than those "pencil thin" straps that came with the Saxon's. This large binoculars also seemed lighter in weight than my previous Saxon 15x70 giants and seemed to be similar to all the other 20x80LW's being sold in the market by Garrett Optical, Oberwerks and the newer Barksa's. They must all come from the same giant binocular factory in China! Anyway enough of the preliminaries, time to give it an optical test run.....
On viewing through the binocs, I was immediately impressed by the immersive views. While I was afraid that the narrower FOV of this binocs would make pointing the binocs harder, I did not find that this was a problem at all. The binoc views also seemed contrastier and more well baffled than the Saxon's. This could probably be attributed to several factors, such as the better coatings and probably a higher magnification ratio as well. Eye relieve was also very, very comfortable on this binocs. For daylight viewing, keeping the eyecups fully extended made for more comfortable viewing as the eye relieve was too much when fully retracted (the eyecups by the way were just right...not too stiff and not too flexible). The added magnification and aperture really flexed its optical muscle on large and bright southern globular clusters, my favourite DSO targets. Omega Centauri in Centaurus and M22 in Sagittarius were a revelation. There was some resolution clearly evident on these objects, appearing granular with some of its brighter members shining through. The Ara and Pavo glob too gave up some of their stars from my mag 5.5 to 5.6 suburban winter skies as did M4 in Scorpius in the binocs (its great to obtain new optical equipment in southern austral winter with gorgeous transparent night skies and the center of our galaxy riding high in the sky). Open clusters (M6 and M7 in Scorpius) sparkled in them as did some of the brighter nebulae (M8, M20 and M17 in Sagittarius). Smaller nebulae showed more shape and structure due to the extra magnification (for instance M17, the swan showed its swan shape much better in this binocs than in the Saxon's). I was once again reminded of how awe-inspiring it was to just scan the central bulge of our home galaxy, the milky way and all its clusters in giant binoculars. While scanning this same region with my 10" dob was cool, there is something about scanning the heaven's with two eyes that speaks to the very heart of our souls. Its something that cannot be described in words! This giant was also great for galaxies as I spied NGC 4945, the great edge on in Centaurus, NGC 5128, the Centaurus A galaxy and M104, the Sombrero in Corvus. The FOV exhibited some expected field curvature, but this was not obstrusive at all till about 20% from the edge of the FOV (performance was very similar in this respect to the older Saxon's). There is of course chromatic abberation on brighter objects seeing that this is only a doublet, but still I had good views of Jupiter and its satellites. And I though I could make out its two main equatorial bands (more easily than in the Saxon's). Cool. Will have to try them on Saturn and the moon when I get the chance. Overall it is a great replacement for my trusty Saxon's. I will probably have more to rave about as I get to use them more over the course of the next few weeks. And did I mention that they are incredibly light (1.8kg) and can be used handheld seated for short periouds. My only gripe would have to be the long length of the barrel (37cm????). Its a lot harder to grasp them at the ends :)
60mm f/11 Yosco refractor, Japan (SOLD)
type : singlet refractor (coated)
clear aperture : 57mm (maybe less with the internal barlow)
focal length : 700mm (f/11)
eyepieces : 12.5mm HM, 8mm HM and 1.5x erector lens made in Japan
other included accessories : 0.965" metal bodied mirror diagonal
finder : 5x25mm
mount : wooden extendable
I got this vintage Japanese made 60mm refractor from e-Bay locally for a very, very low price. On paper and from the pictures, the scope appeared to be a classic enamel white refractor from years gone by. Indeed the construction of the scope was sound. It was all metal (including the finder mount) save the objective retainer ring which was plastic. It had a nice wooden tripod with slow motion controls on the altitude axis, like all the current small refractors and was surprisingly stable. The tripod was also extendable, making for very comfortable viewing at elevated angles. The scope also came with some nice fully coated Japanese made 0.965" eyepieces (a 12.5mm HM, a 8mm HM and a 1.5x erector eyepiece) and a nice metal bodied mirror diagonal. And I really liked the super smooth metal focuser and metal focuser knobs, a rarity on lower end scopes these days. But my first look through the scope proved disappointing. Something was terribly wrong with the scope. For starters the views were terribly dim for a 60mm scope (which turned out to be a 57mm scope as the plastic retainer ring stoppered down the aperture). To further aggravate this, there was what appeared to be metal baffles down the tube. This, in addition to the single coated lens did not make matters any better. On removing the objective lens, I found out that there was an inner barlow like tube with two negative lenses on each end. I tried removing this and then experimented by moving this tube up and down the OTA to increase the aperture but the scope would not come to focus at all. A practise in frustration!!!!! And the stoppered down finder was next to useless and had very poor eye relieve. I ended up selling it as a project scope. Maybe someone with more mechanical know-how could actually make this scope work. It was a real shame as I was all ready to embrace a small, light "grab and go" scope in my arsenal.
Kasai Comet #66 60mm f/6.9 ST refractor(SOLD)
type : achromatic doubled refractor (coated)
clear aperture : 60mm (2.4")
focal length : 415mm (f/6.9)
eyepieces : 0.965" fully coated 8mm HM, 2x barlow plastic body(Japan)
finder : 6x25mm plastic
mount : spindly plastic head metal legged mount adjustable alt-az
Found this really cute looking 60mm short tube scope on e-Bay, also for a very very good price. I have been chasing the perfect vintage 60mm refractor for a while now. Later found out that this scope was made by Kasai in Japan, probably around the time when my firstscope, the Cometron CO-40 was made. This scope sported the same Celestron orange from the 86 Halley's era, the same 6x25 plastic finder with good color correction and good eye relieve, the plastic encased prism diagonal, sturdy plastic/bakelit focuser, and down to the 8mm HM, metal barrel eyepiece that came with my Celestron. The objective was a full 60mm of aperture and was coated (some white reflections)...what a relieve as there were no baffles like in the Yosco. The mount looked very spindly with its plastic bakelit head but held up surprisingly well under the weight of the scope and was very easy to use. The scope only locked in altitude but swivelled freely in azimuth. Nice and smooth! I had some great views of the moon (quite color free...more so than my Orion 80ST) and yielded some very nice views of open star clusters and M42. However I soon discovered that from suburbia, 60mm scopes do not make much sense as they just do not have enough light gathering power to make views worthwhile. The planets, while sharp were small and featureless, even with the barlow. I ended up selling the scope and stepping up to a 4.5" Meade Newtonian OTA.
114mm (4.5") f/8.8 Meade AST OTA(SOLD)
type : spherical mirror with barlow in the focuser setup
clear aperture : 114mm (4.5")
focal length : 1000mm (f/8.8)
eyepieces : none
other included accessories : mounting rings
finder : plastic 5x25
mount : none
Got this OTA only used off Astromart for a very very good price as well and decided to give the barlow in the focuser setup another go. Sheesh seems like I have become more of a cheap but okay scope tester of late rather than a stargazer. I really should be spending more time observing and less time testing telescopes!!!!! Anyway the scope came with a plastic 5x25mm finder and a plastic focuser that was reminiscent of my 6" catadioptric newt's focuser. I first tried using this scope handheld in a camping chair with the 24.5mm SWA in the focuser without much success. Later got it mounted on my photo tripod for futher testing with all three of my premium eyepieces, the 24.5mm Meade SWA, the 20mm KK Widescan III and the 6mm TV Radian. All came to focus, even when the 2x Orion Shorty Plus barlow was employed. Views were much brighter than in the 60mm refractors as expected but also showed a sharp spiking and stars did not focus down to a point. I then pulled the primary mirror out of the OTA and center spotted the mirror and recollimated the scope. Views were much sharper now at low magnifications but still nowhere near as sharp as I would have liked it to be at magnifications of over 100x. My conclusion for these barlow in the focuser scopes is that they are just incapable of higher magnifications due to their spherical mirrors. They would make brilliant large finders for larger scopes but iwould not recommend them as a first scope or as an only scope. Their strength probably lies in low to medium powered views of DSO as some of the globs started to show resolution. I got good views of Omega Centauri and 47 Tucana in this OTA.
113mm (4.5") f/4 Orion StarBlast
type : parabolic mirror
clear aperture : 113mm (4.5")
focal length : 450mm (f/4)
eyepieces : Orion Explorer II 17mm, 10mm, 6mm
other included accessories : single arm dob mount
finder : red dot
mount : dob
Got this cute lil scope from the Orion warehouse in Watsonville in NorCal on my recent work cum holiday trip to California. Was really lucky to get one as it was on backorder (yup visited their main showroom in Cupertino but they did not have it there). But after explaining to the store person that I came all the way from Australia, she called the manager and he agreed to let me have to floor model. Kudos to the legendary customer service at Orion. I now have firsthand experience of their great service!!! Anyway have been wanting to try out this scope for a while now so it was great to finally get my hands on one. There have been so many glowing reports from big names such as Phil Harrington and Geoff Gaherty. Since I got the floor model, there were some things missing such as the starguide CD and the collimation cap. But they did throw in an extra eyepiece, a 10mm Explorer II, in addition to the 17mm and the 6mm. The scope came pre-assembled and packed into a rather large box. The scope also comes with an Ez Finder II zero power finder. On inspecting the scope, the dob mount and the eyepieces, everything was in good working order. The eyepieces showed pleasingly green reflections, not the expected fully coated blue indicating multicoatings. Later testing showed them to be competent performers, even in such a fast focal length scope. I was amazed at how sharp the ep's were all the way out to the FOV. And eye relieve was good in the 17mm, doable in the 10mm and a little tight on the 6mm, with my glasses on. And there was no annoying spikes indicating good baffling. Comparisons with my many element mega FOV eyepieces showed that they allowed more light through. Must have been the number of elements as these are 4 element ep's as opposed to 7 to 8 element in the mega ep's. For instance the 6mm Explorer II showed brighter views than my 6mm TV Radian. Also I found that among my better eyepieces, the 20mm KK Widescan III showed the worse edge abberations with the view only staying sharp in the centre, with seagulls occupying the rest of the FOV, a sign of coma. Must be the function of its huge FOV (84 degrees FOV). And the parabolic mirror makes a big difference. High power views were sharp and color free. A big improvement over my Orion 80ST achro. Side by side comparisons showed that the StarBlast went slightly deeper (but not by much) in comparison to the Orion 80ST. Views were slightly brighter and there is more resolution on globulars like M22 in Sagittarius, M4 in Scorpius and NGC 6397 in Ara. Planetary views were also good and color free although I found that the Orion 80ST consistently gave sharper and more contrasty planetary views (I told you I got a good samples didn't I ;) I think refractors still rule when it comes to showing minute detail in planets, even one as fast as my 80ST. Also the dob mount is a big departure from those shaky aluminium stamped tripods. When placed on a bar stool, I can scan the heavens jitter free. Feels like I am soaring through the heavens in my StarBlast spaceship. My fave combo is the 17mm Explorer with the DGM Optics VHT. Scanning the heart of our milky way with this combo is breathtaking......M8, the lagoon and M20, the trifid nebula in the same FOV. I usually leave the 17mm Explorer II in the focuser for super quick jaunts into deep space on weekdays. I also find the EzFinder II to be very easy to use. having come from a powered finder school of thought. At a recent dark sky getaway, my observing buddy Yixin used this scope and judged it to be a tier above other newbie scopes due to the ease in finding objects using the zero powered finder. I am now a convert to this sort of finders, although I would still use the 50mm finder on my big dob. Having more time with this scope under dark skies have further cemented my love for wide field small scopes. They are such a joy allowing fantastic views of large objects such as the whole Veil Nebula and the North American Nebula in Cygnus (with the NPB in place of course). I now have a dilemma as I have two very wide fields scopes....which one to keep. I think I can justify have two of them :) Anyway I am going to get back to enjoying this great lil scope...later...
Eyepiece and Accessory mini review
24.5mm Meade SWA (1.25”, 67 degree FOV, Japan) : Currently my most used eyepiece, superceeding my previous most used eyepiece, the 32mm GS Super Plossl. This is an extremely well built eyepiece and is very substantial to hold (as in heavy). It is an older model SWA (made in Japan) and does not have rubber eyecups and it comes fully multi coated. The reason for me using this more is that it offers almost the same FOV as the 32mm Super Plossl at a higher magnification. The background is much darker and more detail is visible at this higher magnification. If there was a problem with this eyepiece, I would have to say that the field is not flat in an f/5 scope. This is to be expected. But only the outermost ¼ of the field is distorted with seagulls. With the barlow in, the field is much sharper almost all the way to the edges. Some distortion is still visible but you would have to look very hard.
20mm Orion Expanse (1.25”, 66 degree FOV, China) Got this used off Astromart. It is a rather nice ep with a very large eye lens. I use this extensively in the Orion 80ST at 20x as it is a nice “panning” ep. The background is not as grey as the 32mm at 23x in the C6 probably due to its smaller focal length and its gives a pleasing image scale in the 80ST. My only gripe with this ep is that it seems to have some sort of field curvature and the stars become seagulls about 20% out from the center (though not nearly as bad as the 11mm Chinese UWA). Best used barlowed. Very comfortable eye relieve and I can see the whole FOV. Also multi coated. I usually leave the UHC filter screwed onto this ep when I observe.
20mm KK Widescan III (1.25”, 84 degree FOV, Japan) Got this used off Astromart as well. Its a rather light ep considering the number of elements it houses. Fully multicoated with very nice barrel knurling, nice pliable rubber eyecups and check out the FOV on these. Eye relieve is a little on the tight side but if you put your eyes close enough, you can almost make out the incredible 84 degree FOV. Its like looking out through a porthole into space. This is a poor man's Nagler. The ep is very sharp at the center of the FOV and is noticeably sharper than the 20mm Expanse at both the center and at the edge of FOV. Surprisingly sharp even in two of my f/5 scopes (Orion 80ST and the 10" f/5 dob...the ep would not come to focus in my C6). I estimated it to be sharp till at least the last 1/4 of the FOV. On comparison, the FOV looked similar to the 24.5mm SWA.
9mm UWA (1.25”, 66 degree FOV, China) : My second most use ep in my collection. I tend to grab the 32mm Super Plossl, the 9mm UWA and the 6mm UWA when observing with the C6. Very comfortable eye relieve (no scrunching up to the ep), sharp to the edges (courtesy of its barlowed formula) and it gives a comfortable 166x with the barlow. This is the mag I routinely use when seeing is not up to the mark. This ep seems to be well baffled and I don’t detect any ghosting on brighter objects. My only gripe with this ep is that its field lens is set flush with the edge of the barrel so one must be careful when treading filters to this. Two of the best ep’s in this series.
6mm TeleVue Radian (1.25”, 60 degree FOV, USA): Got this brilliant TV eyepiece to replace the 6mm UWA that I was missing so terribly as the 5mm X-Cel gave too much power on my 6” scope for those not so steady nights. I find myself using 250x more frequently than 300x as the seeing seldom permits such high magnification. I get the same resolution as the 5mm X-Cel in any case. The FOV is slightly larger than the X-Cel and the contrast is markedly superior as there is no flaring on bright objects off axis. Also due to its barlowed nature, this ep is sharp to the edges and does not exhibit any edge of field distortions. One can allow a planetary disc to drift from one end of the ep’s FOV to the other end. Superb high powered and planetary ep that comes with 20mm of eye relieve and a very nice retractable barrel to adjust for non eyeglass wearers. My only gripe is its weight (this is one hefty chunk of glass) and its slightly warmer views on planets and the moon. I have compared the Radian side by side with the legendary Orthos and these do not give up much to the orthos other than the slightly warmish colors. Even the 5mm X-Cel was much better in this aspect! I also prefer to use this on its own without the barlow...fantastic high powered eyepiece.
Orion 2x Shorty Plus Barlow lens (1.25”, Japan): This is the deluxe 3 element APO version from Orion. Also found under the Celestron and Vixen brand as the Ultima barlow, this has been touted to be the best shorty barlow available in the market offering a full 27mm FOV and color free views. Personally after comparing the Shorty and Shorty Plus Barlow, I could not detect any difference in views. Both appear to give the same nice sharp contrasty views. I noted however that the Shorty Plus seem to give slightly more magnification than the Shorty. Contrast and color correction seemed similar to the Shorty to my untrained eyes.
DGM Optics VHT (Very High Throughput) and NPB (Narrow Passband Filter) 1.25". As the filters received rave reviews by Phil Harrington in a rather recent Astronomy writeup and both 1.25" filters were on sale, I decided to bite the bullet and see how well they perform. I could always sell my Lumicon UHC filter off if these two worked out well. After discount, I paid even less for both these filters than the Lumicon. Anyway to cut a long story short these filters are stupendous. They come in very nice round plastic filter cases that snap shut and both filters complement each other very well. The VHT filter is a mid-band filter (as opposed to broadband according to Dan McShane, the owner of DGM Optics) and it gives a very nice balance between bright stars (does not dim them as much and star colors are very natural) and nebulosity. I suspected this filter to be more than just broadband because I could make out a lot of delicate structural detail in M42's wings with this filter and was proven correct when Dan sent me that e mail. As for the NPB filter, this filter gives very high contrasty views (more contrasty than my Lumicon UHC). The background was significantly darker and I could make out added detail in M42's wings and Tarantula Nebula's swirls. Eta Carina was an awesome sight with the filter in with its dark lanes running everywhere in the 10" f/5 dob. My one gripe with the NPB is that stars take on an unnatural hue due to some color bleed reminiscent of the UHC filter. Overall both are great filters at budget prices.
Ex Equipment review:
6mm UWA (1.25”, 66 degree FOV, China): My third most used ep and one that I usually grab with the 32mm Super Plossl and the 9mm UWA. Big eye lens and tremendous eye relieve. Gives about 250x with the barlow in the C6 and this is my “globular cluster” buster. Also very good for smallish planetaries. Sharp to the edges (courtesy of its barlowed formula). My gripe with this ep is its baffling. This seems to be the worst among the UWA (Expanse) series in terms of baffling. It throws up a very large flare when a bright object is just outside its FOV and has extensive flaring on the moon and planets, obscuring detail. Highly not recommended for bright objects but brilliant for deep sky.
15mm UWA (1.25”, 66 degree FOV, China): This is my favourite ep for panning and for some “serious” study with the Orion 80ST. It is noticeably sharper to the edges than the 20mm Orion Expanse and gives a much darker background (and brighter objects due to the scale) at 27x. It still has pretty good eye relieve though not nearly as good as the 32mm Super Plossl and the 20mm Expanse. I have to get in close to see the whole FOV. This one probably has the shortest eye relieve of the whole Expanse series but the better ones in this series with regards to edge of field correction and flaring. Nice multicoated eye lens for all in this series.
5 mm Celestron X-Cel (1.25”, 55 degree FOV, China): My planet, globular and planetary buster ep. This one only gets out when the seeing is perfect (for 300x with the barlow). Less than perfect seeing and this ep with not focus sharply (which happens all too often). Has a huge eye lens and superb 20mm of eye relieve. Very nice fully multi coated optics as well. Also a barlowed formula and as such is sharp right to the edges. Very well baffled and there is very minimal flaring. In comparison to the 6mm UWA, it is light years ahead. Bright objects also appear more neutral toned in comparison to the 6mm UWA (probably due to its color correcting ED lenses). During moments of good seeing, globular clusters are plain awe inspiring. Resolves Omega and 47 Tuc brilliantly (as is M13 and M5!).
Orion 2x Shorty Barlow lens (1.25”, Taiwan): This is not Orion’s deluxe APO version. Its cheap and it serves the purpose. The previous owner blacked the lens edges and darkened the inner tube. Baffling now seems superb and I detect no ghosting with all my ep’s. The lenses seem to be multicoated. Not threaded for filters and it does not have the full 27mm field but gives up very little (if at all..I know I could not detect any difference) in comparison to the Shorty Plus.
Baader Moon and Skyglow filter (1.25”, Neodymium): A do it all filter for planets , the moon and hopefully DSO’s as well. I had to find a replacement for my “green” moon filter. As it is made of neodymium, other than cutting down some light, it also serves to isolate the RGB lines and as a result, the colors are more neutral. The moon looks distinctly greyish (rather than yellowish) in the 80ST and looks much like the views in my C6. It is also supposed to block some light pollution although I can’t really see an improvement (well maybe a little bit on M8 and M27). I eventually sold this filter as I find that I can still tolerate some chromatic abberation and hence was not really using it much.
Orion SkyGlow filter (0.965”, Japan): My first light pollution rejection filter. Definitely a marked improvement in bright emission nebula and planetaries from the suburbs, although the UHC showed heaps more subtle details and nebulosity. Also enhances the views of reflection nebula’s although not by much. What I did find is that it also improves the views of Jupiter and it does not cast weird shades of green as the UHC does. I eventually got rid of this filter due to its lack of use (plus it being in the 0.965’ size) although I still sometimes miss it.
Lumicon UHC filter (1.25”): How did I ever live before getting this. My most used accessory after the 32mm Super Plossl. This filter improves the views of bright emission nebula and planetaries incredibly (even in the small 80ST!). From my mag 5’ish suburban skies, M42 sprouts wings and tendrils, M8 occupies a large space with its dark lagoon etches into its nebulosity, the Trifid’s (M20) dark lanes are prominent and the Helix Nebula’s dark center is very visible. The Dumbbell Nebula appears almost photographic in appearance. From a dark sky in the 80ST, the whole Veil Nebula is visible as ghostly wisps and the North American Nebula sticks out. And handheld I can see the Rosetta Nebula....cool! My gripe with this one (seems like I have heaps of gripes!) is that its thread is very shallow and this does not work well with some ep’s (no grip at all!). Also there is some color bleed so stars appear unnatural in color.
11mm Chinese UWA (1.25”, 80 degree FOV. China): Got this out of curiosity. The FOV was huge but eye relieve was extremely short, the eye cups were not pliable (could not stay folded down) and it just does not go with short focal length scopes. Sold it in a jiffy as both my scopes were of a short focal length. The FOV was sharp only at the very center and was noticeably unsharp 30% out from the center.
20mm Guan Sheng Super Plossl (1.25”, 52 degree FOV, Taiwan): Fully coated and it has a nice metal body with knurling for grip, rubber eyeguards and came threaded for filters. The first of my higher quality eyepieces (note that all the Super Plossl eyepieces came from Guan Sheng-GS in Taiwan). A step above the Kellner’s that came with the scope. My most used eyepiece then. Perfect plossl with images sharp right to the edges. The only problem with this was its tighter eye relieve. Could not see the entire FOV with my eyeglasses on. Ended up selling this.
32mm Guan Sheng Super Plossl (1.25”, 52 degree FOV, Taiwan): I use this eyepiece the most among all the eyepieces’s in my collection (in the C6 at least and before the 24.5mm Meade SWA came along and spoilt me with the wider FOV). It offer’s a nice flat field almost free of aberrations and is sharp to the edges (well maybe some slight coma in the C6 at 23x but you had to look very very hard) even without the 2x Shorty barlow in place. From my mag 5’ish suburban skies 23x gives a very grey background. I prefer to use it at 47x with the Orion 2x Shorty barlow as the skies are markedly darker and the image scale is a little more pleasing. Eye relieve is very comfortable and I can see the whole FOV without any problems with kidney beaning. Also has the added bonus of being fully multicoated with a nice metal body, a knurl’s finger grip and is threaded for filters.
25mm Guan Sheng Super Plossl (1.25”, 52 degree FOV, Taiwan): This is one of the two 1.25" ep's that came with the 10" GS dob. Its a surprisingly nice ep with fully multicoated lenses (very evenly coated under inspection), knurled rubber grips, pliable rubber eye cups and even safety undercuts to prevent any mishaps (GS makes the best low cost astro equipment in my opinion). I had it checked out and compared with some of my current ep's and while the FOV was a very restrictive 52 degrees, I was astonished by the contrast and sharpness of the ep's. GS sure makes very good ep's for the price they change. However I decided to sell it off as I have been spoilt by my wider angle ep's.
9mm Guan Sheng Super Plossl (1.25”, 52 degree FOV, Taiwan): This is one the other ep that came with the 10" GS dob. Like the 25mm Plossl, it is also a nice ep with fully multicoated lenses, pliable rubber eye cups and even safety undercuts to prevent any mishaps. The only thing different about this ep was the lack of knurled rubber grips. Contrast and sharpness was very good as well but the tiny eye lens was very discouraging to eyeglass users like me. Ended up selling this as well.
12.5mm Guan Sheng Super Plossl (1.25”, 52 degree FOV, Taiwan): Fully coated with magnesium fluoride and also very sharp right to the edges. Came with nice pliable rubber eye cups and knurling on the barrel. Also threaded for filters (standard thread which was good). Very good medium powered ep and gave great views of Omega Centauri, 47 Tucana and the larger southern globs. However extremely tight in the eye relieve department. Sold this off.
6mm Celestron SMA (0.965”, China): Very sharp and well corrected ep. Too bad eye relieve was non existant and it was in the 0.965” format. Fully coated with a nice metal body and threaded for filters. Noticeably brighter than the 8mm Celestron HM ep probably due to the age of the ep and the coatings. Sold this as well.
25mm Celestron Kellner (0.965”, Japan): Very old ep now but still very good. Seldom used due to its 0.965” size. Kept this for sentimental reasons. Fully coated with a nice metal body and threaded for filters but no rubber eye guards. Gave very good low powered views of some of the larger Messiers and mated very well with my now defunct 0.965" Orion SkyGlow filter (threaded for filters) and very well built by todays standards. Was also used on my 3" and 6" equatorial scopes for testing.
8mm Celestron HM (0.965”, Japan): Served its purpose in the early and mid 80’s as my planetary ep. Eye relieve was non existent and it was not even as sharp as the 6mm Celestron SMA. Also fully coated. But it did show me Saturn's rings, Jupiter's two main equatorial belts and 4 moons and polar ice caps and surface markings on Mars at opposition in the mid 80’s so it can’t be all that bad. Threaded for filters and built much more solidly than the current crop of 0.965" eyepieces coming out of China.
25mm Kellner, 9mm Kellner and 6mm Kellner (1.25”, China): These were the original ep’s that came with the 6” E-Bay’ish catadioptric. Used the 25mm Kellner heaps (good eye relieve although the FOV was very limited….probably around 50 degrees). All of them came fully coated with nice uniform blue magnesium fluoride. No rubber fold down eye guards or knurling on the barrel though. I did not get to fully test out the other two smaller focal lengths due to the Cat’s limited resolving power and sharpness due to the built in barlow so I cannot really comment on the quality of these eyepieces. All I can say was that the eye relieve on these were minisicule. Also the threads were not standard and as a result I could not screw on any of my filters. Was only workable with the green “moon” filter that came with the scope. Sold them as well.
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