Your astrophotos

Re: Virgo Cluster

NCTiger — Tue, 06 May 2008 13:01:19 GMT

Worked on Virgo galaxies again last night. Used a Canon 200mm f/2.8L lens on the 40D for some widefield shots. Was able to get seven Messier galaxies (and a number of NGC and IC galaxies) on one frame - stacked 10 subs at 85 secs with four darks and two flats:

Re: Virgo Cluster

NCTiger — Thu, 01 May 2008 21:13:30 GMT

Did some additional imaging last night of a portion of the Virgo Cluster - centered on M-58. Picked up several more Messier galaxies and several NGC galaxies.

Here's the negative - some of the smaller galaxies show up better:

Re: Virgo Cluster

NCTiger — Tue, 29 Apr 2008 14:39:14 GMT

Thanks Starwolf - have a moderate light pollution problem from my backyard, difficult to get to a dark sky site - hoping to do so this weekend. That should help darken the background somewhat. In the meantime, I set up last night in my backyard and did a wider field shot of the Markarian's Chain. Used a 300mm lens on my Canon 40D at f/4.0 and ISO800. Stacked five 4 minute subs with two darks and two flats in DSS. Used the Hutech light pollution suppression filter on the camera.

Re: Virgo Cluster

Starwolf — Sat, 26 Apr 2008 15:10:39 GMT

Very nice indeed. All you really need to do is darken up the background a smidgin'. I think it is an excellent shot.

This area is indeed Markarian's chain (It starts with M84). It's approx 60 million LY distant.

Re: Virgo Cluster

NCTiger — Sat, 26 Apr 2008 01:58:51 GMT

Do you know the name of that chain of galaxies in your picture?

I believe it's a portion of Markarian's Chain.

Why are you using ISO 1600? Unless you are taking your images in pristine dark skies avoid using such a high ISO. An ISO of 400 will yield much less noise and won't wash out as quick.

Force of habit I guess. I'd been imaging with no guiding for several months, so I used the highest ISO to take the shortest exposures. I'm beginning to get the hang of auto-guiding, so I should be able to back off on the ISO. I'll try the 400 speed at my next opportunity (if we ever get clear skies in this part of western N.C. again!).

Thanks for the comment and suggestion.

Re: Virgo Cluster

tkerr — Fri, 25 Apr 2008 22:26:08 GMT

Nice shot, one of my favorite areas to obsereve.

That is only a portion of a chain of galaxies which is only a small portion of the Virgo cluster of galaxies. Do you know the name of that chain of galaxies in your picture?

If I may ask a question and make a little suggestion; Why are you using ISO 1600? Unless you are taking your images in pristine dark skies avoid using such a high ISO. An ISO of 400 will yield much less noise and won't wash out as quick. At ISO 400 you will be able to take a couple longer exposure without getting too much noise or LP wash out, then a bunch of shorter exposures to stack together. Everytime I try anything ISO 800 or 1600 it's too noisy and grainy looking.

Have A Nice __________

Virgo Cluster

NCTiger — Fri, 25 Apr 2008 20:49:34 GMT

I imaged M-84, M-86 and friends a few nights ago between clouds and tree branches. Used the Canon 40D at ISO1600 through an 80mm Stellarvue Nighthawk II, a W.O. 66 mm guidescope, Orion Starshoot autoguider, all mounted on a CG-5. Moderate light pollution, so used a light pollution suppression filter. Series of exposures ranging from 90 seconds to 210 seconds stacked in DSS and processed in PSE4.

Needs considerable improvement. Same scene in APOD for today:

http://antwrp.gsfc.nasa.gov/apod/ap080425.html