Hi All,
Again, not very active, but managing to still push out a few images while abroad – bless internet controlled telescopes. I’m pleased to present my latest effort, M101 – The Pinwheel Galaxy (see image below).
The Pinwheel Galaxy (M101/NGC5457) is a face-on spiral galaxy residing in the constellation Ursa Major. The galaxy’s magnificent structure displays thousands of bright HII regions containing clouds of high density hydrogen gas that is contracting under it own gravitational force. M101 appears asymmetrical on one side due to what is believed to be caused by a near collision with another galaxy. M101 is approximately 27 million light-years distant.
About the image;
The image is and LLRGB composite with a total exposure time 4.3 hours (Luminance:112mins;R:50mins;G:50min s;B:50mins) acquired using GRAS3 (TOA150 w/ST10XME) under the pristine dark skies of New Mexico. I think this is a classic example of why I don’t image much with NABG cameras – I hate blooms. Never got excited about dealing with them. Using an NABG camera for wide field work such as the presented image, you can be guaranteed that there will be a bright star somewhere in the field that will cause grief – hopefully not too close to nebulosity or other prime structure. Give me an ABG that I can bleed with 15 or 20 min subs any day. Quick run down – All subs calibrated (dark/flat/bias/hot+dead pixel removal) in MaximDL. Blooms removed using Ron Wodaski’s debloomer MaximDL plugin. All subs registered in Registar, the combined using Sigma Reject in MaximDL. Three iterations of deconvolution in CCDSharp applied to the luminance. Subsequent processing performed in PS. Gradient removal, noise reduction and selective contrast masking. Colour balance is close to correct – factored in a .6 increase in atmospheric extinction for the blue data. I had problems with the green channel due to what appeared to be a tracking problem, thus stars were elongated. I removed the troublesome green subs and re-combined. No other trickery, other than subtle colour balance tweaks – boosted the red highlight saturation to bring out the HII regions. Seasoned to taste.
My apologies for not providing a high resolution image (reduced to 60% for web presentation). I have problems with my web hosting provider (who suffered a major failure) and as such don’t have a web presence at the moment. I’ve signed up to a more reliable provider, but have not had the time to get everything back online – still need to create the MySQL database for the gallery functions etc. I may also take this opportunity to enhance a few things such as dynamic watermarks etc. Sorry about this (rather unprofessional and not my style). Stay tuned.
The folks at Global-Rent-a-Scope recently came up with some deals for members. Nice discount rates. To put a dollar value to this image isn’t easy to calculate. I typically purchase a lump sum of points – which at times makes it cheaper in the long run. They also calculate based on the percentage that the moon is illuminated. I try not to think of it as single image, but more a service offering. You get access to some nice scopes and the support is great. Arnie and Brad are top guys and quick to resolve any matters that may arise. If you’ve got some general questions, they might be answered by the FAQ - http://www.global-rent-a-scope.com/FAQ/
Simultaneously, I’m also acquiring data on other objects (on different GRAS scopes), trying to plan the runs so I shoot the object only when they are high. Reasonably easy, even if you’re controlling a scope in the US. TheSky helps with all planning and object timings.
Check out their web site for details. They’ve now got a pricing structure to suit the astro-imager, which is much welcomed (compared to the “scientific bunch” rate). Also speak with Fred (Bassnut). He’ll certainly know the plans etc (may even give you an intro rate to get your feet wet.->Fred). Remote imaging, if you’ve never done it before is quite an experience. You’ve got access to scopes across the globe so can image 24x7 if you’re really keen.
Regarding the acquisition process. You simply login, define the target, exposure lengths, quantity of exposures, etc, etc. Then start the run. The raw light frames are downloaded and sent to a central FTP server. Here you can download them, along with calibration frames for each scope. You can then commence your regular image processing functions. Not sure what you mean – “Did you have to wait up while it was being acquired?” There is no need to sit around and watch the operation taking place. I typically kick it off and check the status now and then. When the imaging run is complete, the system automatically logs you off so billing stops.
There is of course other competitors, which may influence the internet controlled robotic market. Another group known as Light Buckets is getting online. Steve from Light Buckets is a good operator. They’ve got a 14.5” RC in WA (Pingelly) and a 24” RC in New Mexico that they’ll have online soon. In fact, the 14.5" RC was commissioned last week and ready for customers. It was delayed due to RCOS TCC problems.
The market may change as this service grows. Nothing but healthy competition to fuel this expanding market. I would like to note that I do not have any affiliation with either GRAS or Light Buckets. I’m simply a consumer of their service.
Slight diversion, but I hope this explains a few things. Thanks again for your praise.
Good detail in the image but it appears to have a touch too much magenta on my monitor.
It's interesting how our NH friends complain that all the good stuff resides in the SH, but they have it over us when it comes to galaxies. I'd certainly like to tackle these objects.
Cool shot Jase I do love a Galaxy just hanging in space.
I just want to advise folks that the FAQ that was linked in Jase's post is somewhat outdated, sorry. Its due to GRAS recently switching to 100% ACP-GRAS control SW on all the G's. ooops
This FAQ still needs to be updated to reflect this and will lead to some confusion methinks. My apologies for the tardiness, but priorities press on and things are in a constant state of evolution here
Better off going straight to the video tutorials and get stuck into it fast
Excellent pic Jase, I like the colour balance, looks vibrant.
You like ABG cams !! . WHAT happened to doing it the hard way, he, 4m FL, sensitive NABG , hours handcrafting every detail in PS, and even more hrs of masterfull healing brush bloom removal massaging. Wheres the ART, the ADVENTURE (your such a woose ).
Seriously, I understand what your saying though, NABG can be a real drag, but G15 (as you know) with the more linear NABG cam suits science and NB, given time is money and lower exposure times for the same signal therefore can make data capture much cheaper, and of course blooming is much less of a problem with NB.
Cost of useing GRAS ?. For a US$50 trial, you get from 0.8 to 1.8 hrs (depending on scope). This would be ample time for an LRGB killer pic, and considering the ease a pic can be taken and the gear quality available, its a small price for a result that will proudly be presented for a lifetime (well, a few weeks of posting anyway.) And of course it gets much cheaper for other packages. Sorry for the add, but I was prompted .