Galaxies at 300mm

[themos]

Hello, here's an unguided stack of 24 3-min exposures (@ISO 200) with the 450D Canon digital camera. I used the TAIR 300mm lens stopped down to f/5.6. DeepSkyStacker for stacking. IRIS and PixInsightLE for processing. This is reduced x3 and cropped for the web.

M81, M82 and NGC 3077 are visible. They are all in the Ursa Major constellation.

[themos]

UGC5302, a 15.1 mag galaxy also shows up in the full-size image. Also MCG+12-10-013 and MCG+12-10-019. These were found by using IRIS to do astrometry of the image(http://www.astrosurf.com/~buil/iris/tutorial13/doc31_us.htm) , then finding faint fuzzies in an IRIS negative. Circling the fuzzy with the mouse, IRIS gives RA/DEC coordinates (right-click menu "Compute") which is then fed into the Aladin online viewer http://aladin.u-strasbg.fr/aladin.gml

[Beyond_Vision]

Good focus and good star shapes to the corners Themos. It would be worth taking some flats which would give it a real lift.

Regards

Kevin

[themos]

Yes Kevin, that lens is not bad at that aperture. I've turned it into my grab-and-go refractor by sticking a Nagler 12T2 at the end.

I will write down "I must shoot flats" 100 times. You can see a nasty "hole" in the picture. But I am quite surprised at how much "science" information one can get from shots of this type even when they don't look very pretty. The astrometry and photometry tools in IRIS are great fun.

[Beyond_Vision]

It's not to late to take the flats since it was taken with a camera lens which would be in a fixed position.

It's a very powerful program for a freebie if you can get used to the interface and as you say it's nice to get a bonus to get some measurements made from an image too.

Regards

Kevin

[themos]

It is too late for this one because more/different dust spots have appeared!

Also, my estimation of how many calibration shots are required has gone up a lot since reading HAIP.

[themos]

Ok, this is fun and interesting. The Aladin stand-alone java application is rather good. You feed it your image, you do some astrometry on it ( look at the tutorial in CDS tutorial) and then you can bring up all kinds of catalogs to mark up your image. Here is a version with Tycho-2 stars marked in blue circles and PGC galaxies marked in yellow crosses.

[zhgutas]

Very nice Themos! I simply love widefields, and this is a cracking one too!

Marius