Tuesday, November 10, 2015

The quest for the deep...hunting Stephan's Quintet and the Deer Lick Galaxy's fleas in Pegasus

"Annotated deep field of the Deer Lick and Stephan's Quintet Galaxy Groups"

Prelude

One of the things I set out to do as a visual astronomer was to strive to go deeper whenever possible. I made a pledge to do this when I got my 10" GS dobsonian back in 2007, and go deep I did, seeking out fainter fare, detail in fainter objects, as well as pushing the magnifications as high as I could to eek out as much detail in the brighter planetary nebulae and globular clusters. One thing that always eluded me though was galaxy clusters. The Abell's and the Hickson's were still out of reach, and my best guess is that the smallest sized scope for such an endeavour would be at least a 12.5" scope. I am partially right though, some of these are doable in a 10". That said there is no detail visible, and under most circumstances all you see is one extremely faint blob with no resolution of its individual members.

Abell and Hickson Galaxy Clusters

So what are the Abell and Hickson's? The Abell catalog of galaxy clusters is an all sky catalog containing 4,073 rich galaxy clusters. The original list, published in 1958 by George O. Abell only contained 2,712 galaxy clusters, the "Northern Survey". This catalog was revised and 1,361 clusters from the "Southern Survey" was added by co-authors Harold G. Corwin and Ronal P. Olowin in 1989.

The Hickson Compact Group, also known as HCG is another collection of faint and compact galaxy groups, numbered at 100 and published by Paul Hickson in 1982. The most famous of this is of course one of my quarry's, HCG92, Stephan's Quintet. Both the Abell and Hickson catalog of objects are regarded as observational targets for advanced visual astronomers with big telescopes from the darkest skies!

The most famous and probably most observed of these clusters is Stephan's Quintet and NGC 7331, the Deer Lick galaxy group (and its smaller companions, the fleas). These two objects are only just above the threshold of a 10" scope. While NGC7331 is easy, the fleas are not visible. As for Stephan's Quintet, well lest just say all I though I saw was a faint haze that was barely there with averted vision. There was no galaxy cluster per se. That makes what I just accomplished all the more impressive, and this with a scope a fraction of the size of my 10". Least to say I am a convert to CCD imaging. Presented below is an image I took of section of the cosmos that showcases the above-mentioned galaxy clusters, in the northern reaches of Pegasus the winged horse. Not only does the Quintet make an appearance, I can actually make out its individual members (see asteriks denoting the members).

Also in the same frame, we have NGC 7331, the Deer Lick Galaxy and its companion galaxies, the fleas. This image was a composite of 10x42sec exposures through a 70mm Celestron Travelscope optical tube assembly riding on a NexStar GOTO alt-az mount, no tracking! The CCD camera of choice is my new-old Meade DSI II OSC. Since the focal length of the OTA is only 400mm, my guess is that my 102mm OTA at 1000mm would frame it better...and frame it way better it did. Below is the result of last weekends dark sky imaging trip to Saratoga Gap. All the major members are now fully resolved, and I have annotated my images. See figure legends for details of the subs and exposure times. I can only imagine how much more can be captured if I had a EQ GOTO mount for longer sub exposures. But I am happy with what I captured with my cheap and simple imaging gear!!!!

Wide Field Imaging of both clusters in the 70TS at 400mm focal length on NexStar GOTO

"Stephan's Quintet and Deer Lick Galaxy clusters: 70TS: 400mm focal length: 10x42sec"

A Closer Look: Imaging with the 102GT at full focal length 1000mm on NexStar GOTO

"Deer Lick Galaxy: NGC7331, NGC 7735, NGC7336, NGC7337, NGC7340: 102GT: 1000mm focal length 20x21sec"

"Stephan's Quintet: NGC7317, NGC7318, NGC7319, NGC7320, NGC7320C: 102GT: 1000mm focal length 20x21sec"

The results I obtained for this "deeper sky" imaging session was indeed very encouraging. I might try my hand with imaging some of the brighter Abell and Hickson clusters the next time the new moon comes around. Stay tuned for more......

Monday, November 2, 2015

Astro nostalgia: My vintage scope collection

Isn't it funny how a lot of our life choices are dictated by a certain time point in our development. For me, I seem to be stuck in an eternal 80's loop. All my hobbies, my music choices, etc are 80's centric. Well I was born in the early 70's, but did most of my growing up in the late 70's and early to mid 80's when I started to take note of the world around me. Amateur astronomy was a big part of those years. Star Wars burst onto the big screen in 1977 and that had a HUGE influence on me! The telescope was like my X Wing fighter as I took off to the stars every clear night at my parents yard. I remember those years as they were just yesterday, getting my first scope, a dodgy plastic objective, plastic body tabletop toy 40mm scope with eyepieces the size of a peashooter. I would later come into the possession of my dad's beat up 20x50mm porro prism Japanese made binoculars, and a Celestron Cometron CO40 with real two element fully coated achromatic objectives. I used the buggery out of those two to observe celestial bodies and deep sky objects, moving around my parents front lawn, yard, and even climbed onto the roof to spy Halley's Comet in the predawn sky. Contrary to what most beginners experienced (maybe it was just my tenacious scientific nature), the small aperture did not deter me from digging deep and trying to see as much as I could. I remember going to the libraries to look for star charts, and writing to the local astronomical society, based in my country's capital of Kuala Lumpur. I exchanged several letters with Professor SM Chong as he gave me tips and sent me photocopies of star charts, etc. I will never forget his patience, mentoring this young budding scientist. Thank you prof if you ever read this!!!! I also exchanged several letters with the BAA in UK. I did not have the money back then to join any society but they were very patient and sent me photocopies, just like prof.

Upon reflection, I now realise that the bulk of my observing menagerie consist of used scopes which I purchased over the years via Astromart getting back into the hobby in 2001. I put together a list, as well as photographs of me and my scopes! The trend continues on till today. Most of my scopes are Celestron's (my first scope was a Celestron), and all of them belong to the 80's. Enjoy!

Turn back the clock (by Johnny Hates Jazz):

Celestron Cometron CO40 (40mm f/20) Alt Az Japan (mid 80's vintage)

The scope that started it all for me. I know its extremely small by today's standard's, and most would probably label this as a CTT. Celestron had these for sale to capture the Halley's Comet craze flyby. The optics are fully coated but this scope showed me so much, from Saturn's rings and Jupiter's belts and moons to deep sky delights such as M8 and M22. Scope has the nostalgic Cometron orange bakelit tube, 5x24 stoppered down finderscope with metal base, a plastic body prism diagonal and a 25mm Celestron Kellner and a 8mm Celestron HM in 0.965" size.

Celestron Cometron CO60 (60mm f/15) achromatic refractor on Vixen Polaris Mount EQ (mid 80's vintage)


"Celestron Cometron CO60EQ"

This is the scope that ended my search for the ultimate vintage 60mm scope, having gone through no less than five 60mm scopes (Kasai 60mm ST, Yosco 60mm, its alt az brother CO60, Orion OmniVista 60mm ST, Meade 226 60mm and even a Burgess 65mm BackPacker ED). Its long focal length does extremely well to suppress chromatic aberration yielding very neutral color images, similar to the above scope. The scope came with the same crappy stoppered down 5x24mm eyepiece with metal base, a much better metal bodied prism diagonal and just one eyepiece, a 10mm Celestron Kellner in the 0.965" size. The best part of this ensemble is the mount that comes with the scope, the much vaunted Vixen Polaris mount. This mount it totally overkill for the scope, and back in the day came packaged with their 80mm and C6 scopes!!!!!!

Edmund Astroscan (105mm f/4.2) newtonian reflector (unknown vintage)


"The dimunitive Edmund Astroscan"

Always wanted one of these bombproof scopes. Glad I got one since Edmund is currently no longer manufacturing them! I know the parabolic optics are sealed and non collimatible and it is only good for low powered wide field scanning but boy is this scope a joy to use, so long as you have something to set it on. All you need is a dark sky, some sort of pointing device (since its hard to sight down the tube due to its bulbous back). My favourite eyepiece to use with this scope is my 13T6 Nagler! Since I got this used, it did not come with the original eyepieces, the Edmund RKE eyepieces. Also there was no non powered finder on mine so I got a red dot finder for the scope. I plan to hand this scope down to my lil one in the future. In fact she has already started using it! Came with the shoulder strap and metal base.

Celestron Vixen C6 (6" f/5) newtonian reflector mounted on Vixen Porta Mount (mid 80's vintage)


"Celestron C8 SCT"

My first real scope was a beat up C6 with super excellent optics that constantly surpassed the views in other Chinese and Taiwanese made 6" f/5 scopes. I think it was the "special" coatings on the optics cause my scope constantly went deeper in comparison to the mentioned (compared side by side with other 6" f/5 scopes). Gorgeously sharp views of Jupiter's cloud belts, the big red spot (salmon spot ;), Saturn's Cassini's Division and C ring and super sharp views of DSO's. Fave eyepiece to use in this scope was the Orion Expanse 20mm. Surprisingly very little detectable coma for such a fast scope! There are some caveat's though. The sliding focuser takes a little getting used to and personally I prefer rack and pinion or Crayford focusers. Also the secondary mirror is a little larger than required for visual use, although the stated literature says that this is required for full field immunimation for astrophotography. Since I got the OTA only, there was no finder, mount or eyepiece on mine. I used it on am EQ3-2 mount for years, and recently on a Vixen Porta Mount. Now that I have a Polaris mount (see above), I hope to get a new set of tube rings so I can mount this on the mount it was old with!!!

Celestron C8 (8" f/10) SCT mounted on Orion VersaGo III (mid 80's vintage)


"Celestron-Vixen C6 Newtonian"

My current largest scope and what a performer!  Replaced my bulky but trusty 10" dobsonian with this OTA. I am beginning to understand the allure of a large SCT! You do see much more sitting down and observing. I was always bending and contorting when using my dob, even when seated as I did not have one of those fancy adjustable astro chairs! Views are just as bright and detailed as in my 10" dob, and it is so much easier to move around (big factor for me as I like moving around the yard when observing). Also great when I was living in a two storey apartment, and we did not have a lockup garage. With this scope I can carry the whole observing rig in one sitting. With the dob it was two trips, the tube and then the mount. Although not super heavy, it was super awkward to move due to the length and girth of the optical tube. All I got was the OTA, Telrad finder, and a 1.25" visual back so I had to supplement the scope with an optical finder (I prefer the 50mm finders for larger scopes), a diagonal (purchased a 2" Orion SCT diagonal used) and a low powered wide field eyepiece (my lowest powered 1.25" is my Meade 24.5mm ep and that gave  81x). Got the Orion DeepView 40mm three element ep as this gives the lowest and brightest views. No need for fancy ep's in a scope with a long focal length!

Epilogue

There are still some 80's scopes which I have set my sights upon that I have still to acquire. The two include Edmund Scientific's 76mm red tubed newtonian on an alt az equatorial (yup it is set at an angle!) and Celestron's Schmidt Newtonian Comet Catcher (Orange Tubed Version). Whether I get these, only time will tell. I only purchase something if I can get it at a good price!!!!!


Tuesday, October 27, 2015

Let's talk about planetary nebulae!

When I first got back into visual stargazing in 2001, one of the objects that was top on my list to re-discover and re-observe with my then largest telescope, a 76mm f/9.3 newtonian reflector, was a planetary nebula familiar to most amateur astronomers, M57, The Ring Nebula. I have always been fascinated with planetaries. However back in the day, when all I had was my trusty 40mm long focal length Celestron Cometron refractor, I was severely limited to only the brightest planetaries, M57 and M27. From my rather light polluted backyard in the 80's (back then probably red zone skies??!!), I spied a fuzzy star where M57 was to be. Yup no doughnut visage visible. The 3" reflector opened up a whole new world for me. The doughnut was not only there, it was rather bright too. And M27, the first planetary nebula to be discovered in 1764 by french comet ferret Charles Messier,  showed its dumbbell shape in my small scope. The nebula looked almost photographic in appearance after I obtained a Japanese made Orion SkyGlow filter in the 0.965" size. So began my love for planetary nebulae. With a narrowband filter, I began my quest to bag as many planetaries from my balcony observatory in Indooroopilly, and my dark sky site in Leyburn, Australia. Visually, mid sized planetaries were the easiest and showed the most detail. Large planetaries, such as the Helix Nebula in Aquarius, show up best in RFT's from dark sky sites with a narrowband filter. The most challenging of the planetaries were the small minute ones. These appear as tiny pinpricks no bigger than the stars themselves. The trick here is to "blink" them using a line filter such as a OIII filter. This is a trick used by advanced visual astronomers to confirm their quarry, since these filters dim the light from stars while allowing the light from the planetaries to pass through.

So what are planetary nebulae and how do they differ from supernova remnants? Well planetary nebulae are formed by stars that don't have sufficient mass to support a cataclysmic explosion to form a supernova. The usual suspects that puff out a shell of glowing gas after it has exhausted all its fuel are old red giant stars. Planetary nebulae are relatively short lived phenomenon, lasting only a few tens of thousands of years. As such they form all sorts of interesting shapes, some of which are visible to visual astronomers. Below are a selection of planetary nebulae that I have sketched and imaged. I have included a description of them and how to appear visually in a scope.

M57: The Ring Nebula, Magnitude: 8.8 Size: 230" x 230" (Lyra)

Discovered by Antoine Darquier in 1779, and a month later by the famous Charles Messier, this is one of the showcase planetary nebulae you see in the textbooks and observing manuals. Indeed it is one of the brighter and showier objects for beginners to deep sky observing. I remember seeing this object for the first time in my Cometron 40. It was nothing more than a blurry star. Probably due to its lack of light gathering power, no amount of magnifying allowed me to see the celestial doughnut visage. Years later, in 2001 to be precise, I saw this same object, as it should be seen, in my 76mm newtonian a ghostly ring of smoke! Now with several tens of years of visual observing under my belt, I can spot this object and make out its hollow tube visage even in a 60mm refractor. To see the inside of the hollow illuminated by ghostly luminiscensce you need at least an 8" scope. This object is even detectable as a out of focus star in my 8x40mm binoculars from dark sky sites. An easy object to image too!

M57 at 1000mm 102GT, DSI II

M57 at 400mm 70TS, DSI II

Sketch of M57 at 166x in the 6"


M27: The Dumbbell Nebula Magnitude: 7.5; Size: 8' x 5.6' (Vulpecula)

The first planetary nebula to ever be discovered, this is one of the few planetaries that looks like a planetary in small instruments. If all you have is a small pair of binoculars (most commonly available garden variety 7x50mm binoculars), this is the planetary I would recommend, since it is large and bright enough to cut through light pollution, and unlike the other smaller ones, this actually looks like its namesake! Through the telescope, it starts to strut its stuff, appearing almost photographic in appearance, with the help of narrowband filter of course. To me the nebula looks more like an apple-core from light polluted sites without a filter. Under dark skies, with a narrowband filter, this same nebula looks more like a football than a dumbbell or apple-core. What's cool about this nebula is you can actually see the background stars shining through the nebulosity!

M27 at 1000mm 102GT, DSI II

M27 at 400mm 70TS, DSI II

Sketch of M27 in at 47x the 6"

M76: The Little Dumbbell Magnitude: 10.1 ; Size: 2.7 x 1.8 arcmins (Perseus)

This is one of the supposedly harder objects to spot in the Messier list and one I had never seen due to its very northerly location. I found this object "easy" even from white zone skies in Los Angeles in my 6" (and later discovered that this object was also visible with a filter in my 102mm GOTO refractor), and this without the use of a narrowband filter. I guess the imposing visual magnitude discourages beginning observers from even trying. While it was "detectable" without the filter, I found the views to be vastly improved with the use of my DGM NPB narrowband filter. The views were even better when I obtained a OIII line filter! Appearing as a bar of light, this object need high magnification to do it justice. Imaging this was also ridiculously easy, and the CCD brought out the colors in the object!!!!

M76 at 1000mm 102GT, Meade DSI II

M76 at 400mm 70TS, Meade DSI II

Sketch of M76 at 37x in 6" and 50x in the 102GT

NGC 7293: The Helix Nebula Magnitude: 7.6; Size: 25' (Aquarius)

The largest and brightest of the planetary nebulae also happens to be one of the hardest ones to detect from light polluted locales. This is due to the fact that the object covers a very large portion of the sky and has a very low surface brightness. This is one object that is greatly enhanced by narrowband filters, and looks the best in very wide field instruments. This object is now detectable even from red zone skies with the help of OIII filters. Imaging wise, this is a brilliant object as it is so big. Color is also very evident, even with 30 second exposures!!!!!!

Helix at 400mm 70TS, DSI II

Helix Nebula at 56x in the 6" 

NGC2438 in M46 Magnitude: 1.8 ; Size: 1.1 arcmins (Puppis)

This is another very interesting planetary nebula that shows abundant detail in small scopes. Found in the southern constellation of Puppis, but high enough for northern hemisphere skywatchers to pick up, it is superimposed on the open cluster M46. Physically they are not associated, but they do make a very pretty pair. Greatly enhanced by the use of a narrowband filter, this one is large enough to not require too much magnification. Imaging this one required me to use a broadband imaging filter due to its altitude in the sky.

M46 and NGC2438 at 500mm 102GT, Meade DSI

Sketch of M46 and NGC2438 at 70x in the 6"

NGC7009: The Saturn Nebula Magnitude: 8; Size: 41" x 35" (Aquarius)

The famous Saturn Nebula does not reveal its secrets easily. I though I spied its famous ansae at 300x in my 10" dob, but that is a big "if" (big part of this is the seeing...and lil turbulence blurs this). Looking more like an bloated elongated star in smaller scopes, I have also yet to capture the "rings" using my 102GT at 1000mm.

Saturn Nebula at 1000mm 102GT, DSI II

NGC2392: The Eskimo Nebula Magnitude: 10.1; Size: 48" x 48" (Gemini)

This is another brilliant lil one that shows abundant detail in larger scopes. Visually I have detected the outer parka, and the subtle triangle in the central region making out the eskimo's face in my 10" at magnifications in excess of 300x. This same feature cannot be made out in the 6", but the outer parka is visible. Photographically I have been trying to get the exposure right to highlight its internal detail. All I have gotten so far is an outer and inner ring without any internal detail at 500mm focal length in the 102GT.

Eskimo Nebula at 500mm 102GT, DSI I

Clockwise: Eskimo Nebula at 400x in the 10", at 156x in the 6" and 70x in the 6"

NGC6818: Little Gem Nebula (Sagittarius)

This is another bright but small planetary that does not show much internal detail even in a 10" scope, but it does show a disc at higher magnifications. Color is evident visually in scopes 6" and larger. The best CCD image I have of this brilliant planetary was with the 102GT at 1000mm focal length, showing a nice lil green disc. 400mm just does not do justice to this object!

NGC6818 at 1000mm 102GT, DSI II

NGC7008: Fetus Nebula Magnitude: 12; Size: 1.4' x 1.1' (Cygnus)

Never knew what I was missing with this one. Amazingly bright and rather large, it is one of those you want to "scrutinise" at higher magnifications, if you have sufficient aperture. I have still yet to train my bigger scopes on this lil beauty. That said it looks pretty even in a 4" scope. CCD imaging brings out a whole level of detail. Even with my 70mm TS OTA there is abundant detail in this object. I need to re-image this at full focal length to see if I can get more detail out of this object.

NGC7008 at 400mm 70TS, DSI II

NGC3242: Ghost of Jupiter/ CBS eye Magnitude: 8.6 ; Size: 25" (Hydra)

One of the planetaries that actually looks like its namesake, this is a fairly large object which shows abundant detail in large apertures. Also known as the CBS eye, this curious feature is actually doable in apertures as small as 10". I have seen this at 300x magnification! This same feature is invisible in my C6! Have to try for it in my C8 next time I have a look at this. Imaging this with my Meade DSI II OSC was a lot harder than I though due to overexposure. I am still coming to grips with getting the exposure correct for the more compact and high surface brightness planetaries.

Clockwise: NGC3242 at 400x in the 10", 112x in the 6" and 56x in the 6"

NGC5189: Spiral Planetary Magnitude: 8.2; Size: 90 x 62 arcsec (Musca)

A strictly southern hemisphere object since this DSO is found in the small constellation of Musca, the fly. I remember my first views of this object through a SAS member's 16" truss dob (thanks Kevin Dixon!!) and though I was looking at a very detailed spiral galaxy!!! I later found out that this was a planetary nebula, and a very pretty and unique one at that. Also I discovered that it was bright and showed a lot of detail even in my C6 scope., even from light polluted Brisbane!!! Since it is a planetary nebula, it is greatly enhanced by narrowband filters. I have gotten great views of this in my 6" and 10" scopes even from red zone skies with the filter screwed on. A must see object if you are ever in the southern hemisphere!!!! Just wish I had a CCD cam and a tracking scope back in oz. This would have been an excellent subject to shoot!!!!!

Sketch of NGC5189 at 56x in the 6" 

NGC3132: Eight Burst Nebula/ Southern Ring Nebula Magnitude: 9.87; Size: 62" x 43" (Vela)

Technically this is still visible from the southern states in continental USA, although I have not tried to pick this up just yet. This was one of my favourite planetaries while living in Queensland, Australia, ranking right up there with M57 and M27! Big and bright, this one too needs magnification to do it justice, showing its multi-shell appearance at higher powers in my 6" and 10" scopes. In the 4.5", I can just make out its ringed appearance, although the multiple shell appearance eludes me. Like the rest of the mid sized planetaries, this also looks good from light polluted skies. All that is needed is higher magnification, or the use of a narrowband filter. Wish I could capture this on CCD! Maybe when I visit my old stomping grounds in the future!!!!

Clockwise: NGC3132 at 400x in the 10", 112x in the 6" and 56x in the 6"

NGC6302: Bug Nebula Magnitude: 7; Size: 3' (Scorpius)

This is one of my favourite southern planetaries, and also one which is visible from the northern hemisphere. It is brighter and exhibits more detail that most people realise, showing an elongated bar, with a pinch down the middle. Imaging this object with the Meade DSI II requires a SkyGlow Imaging filter as this object, while not a horizon skimmer, does not cumulate very high in the night sky. Visually, I find I can push the magnification pretty high on this one. Also does very well with a UHC or OIII type filter visually.

NGC6302 at 400mm 70TS, DSI II

Sketch of NGC6302 at 93x in the 6" 

Tuesday, October 13, 2015

What's new from the roost? Full focal length imaging of summer bounties with the 102GT and Meade DSI II OSC

Well I haven't posted in a while. Call it apathy. Call it the lack of motivation. I think it is a little bit of both. I have been actively observing and imaging, just maybe not as voracious as back when I first got my astrophotography setup. Now that I am more comfortable with getting DSO's in the narrow FOV of the Meade DSI II OSC in the wide field 70mm TS OTA, and the 102GT with 0.5x focal reducer, I was just wondering if I could take it a step further and image through the 102GT OTA without a focal reducer. That means I would be imaging at its full 1000mm focal length, as opposed to 500mm with the reducer, and 400mm with the wide field 70. Objects that would greatly benefit from this increased focal length (i.e. magnification!!!!) include globular clusters and planetary nebulae (hence my motivation since summer has only passed and a whole heap of summer DSO's are still ripe for the picking). With the 70TS, I generally found that I could push my subs to 42 seconds and still get sharp stars unguided. This number came down to 30 seconds on the 102GT with the Orion reducer. Playing around with the 102 at full focal length, 21 seconds seemed like the perfect sub exposure. I ran with this, seeing most of the objects I was going to image for the first time were brighter globular clusters, and some old faithful planetaries, that needed the extra oomph to get the details burned onto the pics. Below is a selection of some of the spoils of my imaging session at full focal length from my red zone San Jose skies. Enjoy.....

M30 Globular Cluster, Capricornus "The Wing Chun Wooden Dummy Cluster"

M55 Globular Cluster, Sagittarius 

M2 Globular Cluster, Aquarius

M13 Globular Cluster, Hercules "The Great Hercules Cluster"

M92 Globular Cluster, Hercules

NGC6818 Planetary Nebula, Sagittarius

NGC7009 Planetary Nebula, Aquarius "Saturn Nebula"

M4 Globular Cluster, Scorpius

M5 Globular Cluster, Serpens

M22 Globular Cluster, Sagittarius "Crackerjack Cluster"

M10 Globular Cluster, Ophiuchus

M12 Globular Cluster, Ophiuchus

M28 Globular Cluster, Sagittarius

M80 Globular Cluster, Scorpius

M11 Open Cluster, Scutum

It is interesting to see all of the globulars side by side as this is how they appear in the eyepiece at the same magnification. Till the next time...

Wednesday, July 15, 2015

A tale of two scopes: My obsession with small refractors

Pre-amble


"Cometron CO60E in alt az mode"

What is the allure of small refractors? With their limited aperture, views of most objects are dim, in comparison to larger reflectors. Maybe its the history, the romance. Galileo never had a scope as good as some of the most basic model we have today, yet he discovered Jupiter and its dancing moons! Trying to rekindle the first time, the first views of objects would probably rank highly too. I have been an avid fan of small refractors for as long as I can remember. I have been chasing that elusive "keeper" scope for quite a while now. I remember lusting after these small scopes ever since I obtained my first "real" scope, a humble Celestron CO40 achromatic refractor back in the early 80's. While most people would have probably left the hobby after looking through such a small scope, I was not one of them. Maybe it was my innate curiousity to push the boundaries, to discover what I could see with such a small aperture. It is probably that same curiousity that prompted me to take up my profession, as a research scientist. That childhood spark is still there!

I have gone through several small scopes in the 60mm class since returning to the hobby in 2001. Some notables include the dastardly Yosco stopped down 60mm Japanaese scope (everything about this scope screamed vintage Japanese, except for its less than stellar stoppered down single element optics), the Kasai 60mm Orange ST scope on spindly tripod (Never should have let this one go. One of a kind and probably made by the same good people who made the Celestron Cometron scopes), a fantastic grey tubed Celestron Cometron CO60 (Another throwback to my 80's roots, this was the bigger brother of my CO40. Came with the same shaky mount and 5x24 stopped down finder), yet another amazing blue metal tubed Meade 60mm refractor (This one was actually a very good performer, and the mount was surprisingly steady) and the tank-like Orion 60mm ST OmniVista on a makeshift alt-az slow motion mount. My last two acquisitions might yet be the ultimate 60mm class scopes. Introducting the Burgess BackPacker 65ED optical tube, and my $15 (yup you read right...the person was going to throw the scope out!) Celestron Cometron CO60E.

Burgess BackPacker 65ED Optical Tube Assembly (OTA)


"Burgess Backpacker 65ED"

Chanced on this scope while randomly browsing the Astromart web site, like I always do on a daily basis. Its funny how I never heard of this scope until now, seeing how I am very much aware of Bill Burgess and his "experimental optics and scope". The story with this scope is that Bill was trying to produce a small short focal length scope that had color free optics by using ED optics. He ordered a batch of about a 100, only to discover that the two elements did not sit properly together, and with the non collimatable lens cell, the optics were never going to focus down to a point source. To cut his losses, he sold off the optics, the OTA body and the dew-shield for a song $25. In the know amateur's got wind of this and snapped them up and began experimenting with this "work in progress". Being ever so resourceful, some of these said amateur's got the scope to work. The instructions are still available here.

"Burgess 65ED on Orion Paragon HD-F2 photo tripod with slow motion control head"

Next up was finding a focuser for the OTA. Again Bill came to the rescue and made available a rack and pinion focuser for the said scope. And the rest is history. My copy of this scope came with a respectable single speed GSO Crayford focuser. Being an "experimental" scope, the last owner wanted to make sure I knew its limitations. Being in the Bay Area,, he drove the scope down and we met at Orion Telescopes Store in Cupertino. This scope came with the pre-drilled lens cell for collimation and an attached mounting shoe, much like those found on the early Orion 80ST OTAs. Seeing how the Crayford is not standard fare, the OTA is back heavy and tends to want to gravitate that way when observing. I tried screwing on a short Orion dovetail, but due to the distance between the holes, I was not able to get it to sit properly. Due to the weight of the scope, the OTA would always find a way to rotate out of the dovetail. My solution to this was to mount the OTA on one of those slow motion devices for photo tripods. Surprisingly this worked really well. I found I could use the scope quite comfortably on my Orion HD F2 photo tripod this way. This will make for an excellent throw in the booth of the car type observing sessions.

Optically this scope does one up on two element achromatic refractors as there is less false color on brighter objects. Still in comparison to say a newtonian reflector, the views are markedly warmer. I also found that the scope does not like doing higher powers. There is some flaring off to the side of bright objects. My guess is that collimation is still slightly off and needs to be touched up a bit. Still all in all, the views  I got from this "mere" 65mm scope were on par with my 70mm Celestron Travelscope ST. Where scopes such as these excel are under dark skies and with wide angle eyepieces. Testing the scope from my orange zone observing site in Saratoga Gap, with the 24mm Meade SWA eyepiece, and the 13T6 Nagler, I had a grand time touring the star spangled fields of Sagittarius-Scorpius. The views were markedly brighter than what I remembered in the Japanese made Orion OmniVista. In fact this scope behaved more like my old 80mm Orion ST! So I guess the take home message is that if you stay with medium and low powered eyepieces, this scope can and will deliver. Now time to find a way to mount it for CCD imaging!

Celestron Cometron CO60E


"Cometron CO60E on Vixen Polaris Mount"

Now this is the definition of an excellent Japanese made starter scope. After a couple of nights of testing, I can safely say my quest for the perfect 60mm long focal length scope has ended!
Found this beauty for a song ($15) on Craigslist. The scope was about to be chucked out so I had to go rescue it. Comes with a gorgeous Vixen Polaris Mount (the only EQ mount back in the day that could do double duty as an EQ and an alt-az mount due to its design) and rare as hens teeth 60mm adjustable tube rings! The scope only came with one eyepiece, a nice 10mm Celestron Kellner, a sweet metal bodied 0.965" star diagonal (not like the plastic ones that came with the alt-az Cometron models) and those stoppered down 5x24mm plastic body finders (but with a metal bracket). What I do love about this scope is its longer focal length (910mm versus 800mm on the alt az models) and its fully coated optics (as opposed to the coated optics on the alt-az models). The vintage of this scope is similar to my first scope, the orange tubed Celestron Cometron CO40 (early/mid 80's in time for Halley Comet). I remember seeing adverts by Lumicon for this scope in Astronomy Magazine's 80's issues, touting these scopes as the perfect scope for capturing Comet Halley on film! I would say that would be stretching the truth a little, unless you were doing wide field piggyback astrophotography with a motor drive.

"Vixen Polaris Mount, a hybrid alt-az, EQ mount"

To say that this scope is over-mounted would be an understatement. The mount that comes with this scope is one of the most sought after vintage Vixen mounts, the Vixen Polaris Mount (they are no longer made mind you!). Back in the day you could get several OTA bundled with this spiffy mount. Orion Telescopes used to sell the Vixen/Celestron C6 f/5 (newtonian reflector with the sliding focuser, which I also happen to own!), and a CO90 (90mm long focal length achromatic refractor). Mount a dinky little achromatic 60mm refractor, even with a long focal length, and you got yourself a rock steady setup! What makes this even sweeter is that due to the design of the mount, this can do double duty as a non motorized equatorial mount, or a rock steady alt-az mount. The only thing I dislike about this is the screw on balance weights and the threaded shaft for the counterweights (you can only use the proprietary counterweights on this). Some have solved this by threading on the standard counterweight shaft from its younger brother, the Vixen Super Polaris mount.

"Focuser on the Cometron CO60 OTA"

Optically, I expected great things from the OTA. Based on my experience with small long focal length refractors, this scope, with its even longer focal length (910 mm versus 800 mm on the standard alt az model), color correction would be pretty good. I was right. The scope threw up gorgeously sharp and almost color free views of Venus, an extremely difficult test for two element achromatic lenses.  The king of planets Jupiter showed subtle banding pattern (not just the two expected equatorial bands) and Cassini's Division was plain to see in the scope. And all these using just that one 10mm Celestron Kellner eyepiece which gave a magnification of about 91x. I even snuck in a peek at M57 the Ring Nebula, and while not nearly as bright as the views in my larger scopes, the celestial doughnut was definitely visible. The dark hollow was visible, with averted vision.

I had another chance to test the optics out with a new/old eyepiece I purchased just for this scope. It is a  80's "Halloween" 25mm Celestron Plossl that looks to be in a 1.25" size, but with a 0.965" silver barrel. This eyepiece gives a magnification of about 35x, just the right magnification for wide angle views, with a little bit of power. Due to the size of the barrel, and its long eye relief, I found the eyepiece very comfortable to use with my eye glasses on, something which is usually not possible with 0.965" barreled eyepieces. I scanned the southern milky way with this combination and it was a revelation. Of course views are not as bright or detailed as in my larger scopes. But the views of objects such as M8, M20, M17, M22 and even M28 were nice. From my red zone skies, the globulars were still unresolved globs of light. However the larger emission nebulae threw up a surprising amount of detail from my skies. I will be taking this scope to a darker site at some point because I know what a 60mm scope is capable of after using my now sold Meade blue tubed 60mm. Stay tuned for more reports from both scopes!!!!!

"Scope came with a very nice metal bodied star diagonal and 10mm Celestron Kellner"