Contrast stretching ngc6188

casstony · #1 13-10-2018, 11:48 AM

I was really impressed with Karl's ngc6188 yesterday and decided to have a quick go last night; I only got 24 minutes before it went behind trees.

Also yesterday Jon mentioned 'stretching' which I'd been previously unaware of, so I'm starting to look into that.

When I stacked the 8x3 minutes of 6188 and moved to photoshop the screen was nearly black, but in 'Curves' I dragged the line about 4/5 of the way to the left and heaps of colour popped out. Looking forward to learning more about stretching and trying it on my other images

Karlzburg (Karl) · #2 13-10-2018, 01:40 PM

That looks good Tony.

I noticed after I stacked mine it was just a black screen with just a couple of stars. Wasn't until I worked it a little in star tools that it started to come alive.

Gavin1234 · #3 13-10-2018, 08:32 PM

Great image Tony. Looks like a challenging target too.

Tom359 (Tom) · #4 14-10-2018, 07:39 AM

Your getting quite good at this T, I will be mining all of your knowledge over the coming months FYI. Probs should t-up some coffee and a late evening under the stars soon.

Imme (Jon) · #5 14-10-2018, 07:57 AM

Well done.....that stretching definately brings out the details doesn’t it!

casstony · #6 14-10-2018, 11:20 AM

Quote:

Originally Posted by Imme

Well done.....that stretching definately brings out the details doesn’t it!

Certainly does, especially when the histogram is really skinny (from what I've seen with a brief play around). I got more of 6188 last night and some interesting stuff in the SMC last night - keen to process that today.

casstony · #7 14-10-2018, 11:22 AM

Quote:

Originally Posted by Tom359

Your getting quite good at this T, I will be mining all of your knowledge over the coming months FYI. Probs should t-up some coffee and a late evening under the stars soon.

You're welcome to come over and see how the professionals image Tom

casstony · #8 14-10-2018, 06:02 PM

So I did 6188 again last night with about 2.5 times longer total exposure but shorter subs (2 min instead of 3 min). Less colour came out so I guess longer subs are more important for faint objects.
4 minutes next time

Tom359 (Tom) · #9 14-10-2018, 10:21 PM

Once this wedding thing is sorted your on.