Thursday, April 16, 2015

Random Musings: Visual or Astroimaging, my conundrum and where the future is heading

The Conundrum

I think I am having a mid astronomy life crisis. I am sure every astronomer goes through this at some stage. I am still pretty much a grassroots astro dabbler, abeilt a very advanced one. Its funny how things can change. I am now a full on astro imager, with the occasional dabble in visual (more like casual perusing after I finish imaging). I am still not sure what has changed since for the longest time, I never even had the urge to image. I think there are many reasons to this. The move from my beloved southern skies in Australia was a bit catalyst. For one all those glorious southern sky gems are no longer accessible in the northern hemisphere. I remember the first time I got under truly dark skies here in California. That was at Mount Pinos, Los Padres National Park and while the first trip there was magical (there was snow on the ground the first time I got up there!!!!), the northern milky way was not as enticing as its southern counterpart. In fact as soon as I got there, I started looking in the direction of my good old friends, Sagittarius and Scorpius! And till this day, whenever summer comes around, I still point my scopes towards those southern wonders!

Also living in an apartment building for almost 5 years made a difference to the usage of my once frequently used 10" GS dobsonian. We shared a carport with our neighbors and hence I could not store my big scope in the garage for quick trips out to dark skies. Having to lug that beast in two trips meant the scope was getting less and less use. I ended up using my small scopes more, and ultimately replaced my beloved 10" f/5 with a Celestron C8 SCT OTA, one of the best decisions I ever made so far. Now that I have an Orion VersaGo III, this incredible set up gets used heaps. I can easily carry the whole shebang from one location to the other. Also I am not sacrificing that much in terms of aperture (had both scopes side by side and the the 8" went head to head with the 10"...views were consisently just as bright...even on globulars!).

The third factor was the ease in getting quality gear for cheap here in the USA. "Embarrassment of riches" is an understatement. I would have never dreamed of owning a GOTO scope, partly due to my cheap arse mentality. So when I chanced upon a Celestron NexStar 102GT for under $200 in a local Costco, I literally threw my money at them. That was a good thing too since I have not seen such a good deal surface after that fateful Christmas! A similar scope from other vendors go for at least $350 or more! So what if there is only 4,000 objects in its database as opposed to 40,000! I can always upgrade my hand paddle to a more advanced one later on.

Also since I am now in Continental USA (CONUS for short!), buying used gear from Astromart is a whole lot cheaper (postage cost next to nothing so most sellers absorb postage!)! I quickly found used CCD imagers for cheap on Astromart, progressing from a Meade DSI I OSC, to an Orion DSI OSC and currently my Meade DSI II OSC. While these are not top of the line CCD images with big arse chips, the images they throw up are good enough for me, and are pretty much inline with my grassroots imaging thinking. My current basic astro-imaging set up is a lowly Celestron Travelscope 70mm ST OTA, riding on the Celestron NexStar GT mount (similar to the Celestron SLT and Orion StarSeeker II series of mounts!). With this OTA mount combo, I can go for wider fields without the use of a focal reducer, and have an exposure time of up to 30 second without star trails for my subs!

The Future

"Orion Telescopes SkyViewPro mount"

"Orion Telescopes Sirius Mount"

Now that I have moved from my apartment dwelling into a house with a humongous yard, I have started to re-evaluate my equipment yet again. I have come to the realisation that I really love astro imaging and have been having visions of acquiring a much more precise mount for my lil and not so lil scopes. The criteria for the mount would be that it would have to have full GOTO capability with that 40,000++ object database, and be able to handle at least my C8 OTA(12.5lb) for deeper sky imaging. Several mounts spring to mind, an EQ5 class mount (Orion Sky View Pro with a 20 lb load capacity), or better yet an Orion Sirius Mount (30 lb load capacity), if I go by the two times load capacity rule! I am leaning more towards the latter since the next step up is the monstrosity of a mount, the Synta EQ6 or Orion Atlas mount, that is almost twice the weight of the Sirius mount! If I were to acquire such a mount, I would probably start imaging from home more, and would probably have to invest in a autoguider (shouldn't be to hard to get a used one) and some narrowband imaging filters.

"Meade LightBridge 16"

That said, I have always dreamed of owning that big dob that would let me go really deep. A few years ago, the 10" was doing wonders for me, as I had more free time and darker skies in the outback in Australia. However my lust for more faint light has led me to this conclusion, I would have to make a substantial jump in aperture to take my views of dim fuzzy's with little or no detail (The jump from 10" to 12.5" side by side convinced me of this. A good example is galaxies, in this case NGC 1365 in Fornax. Detail in the spiral arms were "detectable" in the 10" and 8", but looked more like a photograph with averted vision in my buddy's 12.5"!) to details jumping out at you! My dream scope would have to be in the 14" to 16" range. Budget for this would have to be between $1600 and $2000 for a 16" class scope. These would also have to be truss, and since I am still pretty much a cheapskate, I will be looking at purchasing a mass produced scope (i.e. they will be heavy in comparison to the premium dobs out there). One of the strikes against this is I can see myself finding excuses to not use the scope as set up and takedown would be increased! So for the price would I get one of them heavy SkyWatcher or Meade Truss tube dobs, or pay a little bit more for a light weight Hubble optics scope. Only time will tell!

"Hubble Optics 16" UL"


The galaxies of Sextan's, from the red zone 10th April 2015

"Spiral Galaxy NGC 2967 (mag 11.6) Sextan's"

Imaging galaxies is possible from less than perfect skies. All you need is a little patience and a Orion SkyGlow imaging filter :) It also helps when the galaxies are of the small elliptical kind. I had the idea of trawling Sextan's for galaxies after reading an article on Sextan galaxies in Astronomy Magazine's Stars and Galaxies. Most of them are dim'ish but due to their high surface brightness, they were easier to bag.

"NGC 2974 (mag 11), in case you were wondering, the galaxy is on the top left hand corner next to a bright star, Sextan's"

Anyway enjoy these till I get out to dark skies again and try for the fainter ones in the Virgo-Coma region! Exposures are 8x30sec using the Meade DSI II OSC, Celestron Travelscope 70 OTA and Celestron NexStar GOTO mount.

"Spiral Galaxies NGC 3166 and 3169 (mag 10.3), Sextan's"

"Spiral galaxy NGC 3423 (Mag 11.6) Sextan's"

and a special bonus, Leo ellipticals:

"Ellipticals NGC 3607 (mag 10.8) , 3608 (mag 10.8) , with two other smaller galaxies 3605 and 3599"


Monday, April 6, 2015

I have galaxies pouring out of my ears. Another realm of galaxies imaging run. Saratoga Gap 28th March 2015


"NGC 4214 a dwarf barren irregular galaxy in Canes Venatici, Mag10.2"

The title says it all. I have gone stark galaxy raving mad. My current list of targets are all galaxies. Well this is what happens when you have done all the brighter DSO's and can now fully concentrate on the dimmer fare. It also helps that this is galaxy season as we turn away from the spiral arms of our home galaxy and can peer deep into the void where other island universes roam. Its not such a bad thing. There are so many galaxies in the Leo-Virgo-Coma-Canes and Ursa Major regions that making up an imaging list is child's play. I am really digging my current imaging schedule. Also I have learnt so much about my set up that I can now routinely bag dimmer fare. The familliarity with the stacking and processing software make a big difference too! My main problem now is my images are too red. Might have to use the Orion Skyglow imaging filter to tone down on the reds.


"NGC 4244 an edge on loose spiral galaxy in Canes Venatici, mag 10.2"

Having done most of the Messiers, the bulk of the galaxies on my list are now NGC's. This time round I had some fave's that I had seen and sketched in the past from Australia. These included NGC 4656, the Hockey Stick Galaxy and NGC 4631, The Whale Galaxy and its baby, both found in the constellation of Canes Venatici. I am very much in imaging mode at the moment so its imaging from the get go. Somewhere along the way, I lost my visual observing mojo. My plans are to image all that I can and then if there is some left over down time, I do some visual. I am also loving my new high capacity laptop battery as it has such a long life span. Haven't tested it full yet but after almost 3 hours of imaging, the battery was only half used! Nice.


"NGC 4274 spiral galaxy in Coma Berenices, mag 10.4"

The aims for my next imaging run at Saratoga Gap are to mine the galaxy fields of Leo and Sextan's. Stay tuned!!


"NGC 4414, an unbarred spiral galaxy in Coma Berenices, mag 11"



"NGC 4449, irregular galaxy in Canes Venatici, mag 10"



"NGC 4490, the cocoon galaxy and NGC 4485 in Canes Venatici, mag 9.8"



"NGC 4535 barren spiral galaxy and NGC 4519 in Virgo, mag 10.7"



"NGC 4559 spiral galaxy in Coma Berenices, mag 10.4"


"NGC 4631 Whale Galaxy in Canes Venatici with its baby elliptical NGC 4627; Mag 9.8; Edge on spiral galaxy"



"NGC4656 Hockey Stick Galaxy in Canes Venatici, mag 11"



"NGC 4699 Spiral Galaxy in Virgo, mag 11.9"



"NGC 4725 in Coma Berenices. Intermediate barren spiral, mag 10.1"



"NGC 4762, barren lenticular galaxy in Virgo, mag 11.3"

Note all images taken with a Meade DSI II OSC with a Celestron Travelscope 70mm OTA on a NexStar Alt Az GOTO mount, no focal reducers and no filters from an orange zone site. Subs for all are 8x30 seconds unless indicated and captured using Meade Envisage Software.