Keyhole Nebula

[1ponders] (Paul) · #1 07-02-2005, 12:28 AM

My first DSO. Canon300d. f/6.3, ISO1600 Exp 60 sec. single exposure Alt/Az mount . unprocessed except for cropping. Focus is a bit soft.

Can someone let me know the technique for stacking in PS7. I have another 4 images I'd like to stack on this one. And how to autoalign different layers.

iceman (Mike) · #2 07-02-2005, 06:04 AM

Can't you use registax for stacking them?

I adjusted the curves and levels in PS to bring out a bit more detail, probably went a bit too far on it though.. when you process it yourself you might go a bit easier on the curves.. personal choice I suppose.
I also filtered it through NeatImage to reduce the noise.
Oh and there's a few compression artifacts because I processed an already reduced version.

Excellent shot of a great nebula!

ving (David) · #3 07-02-2005, 09:20 AM

gotta get me one of those cameras!

nice snapshot!

[1ponders] (Paul) · #4 07-02-2005, 09:43 AM

I'd thought I'd better post it as it, didn't want to waste time on processing. There seemed to be a clamour for some DSO's, almost as if there was somekind of withdrawl going on or sumphin'

I'm pretty happy with the first attempt though. All I need now is to learn to stack, (to start with anyway)

Robby · #5 07-02-2005, 10:25 AM

You gotta be happy with that Paul,
You can stack using Photoshop. I have not tried stacking large images with Registax, but I would hesitate to do so.
To stack in Photoshop just place each image on a seperate layer. Use difference blending to line them up, then use normal blending on each layer and change the opacity on each layer to subsequent less ratios in the order of...
1 = 100%
2 = 50% (1/2)
3 = 33% (1/3)
4 = 25% (1/4)
5 = 20% (1/5) etc.....
Alot of DSLR uses use Images Plus for stacking & aligning, but I'm too tight to buy it. PShop seems to work fine.

Hope this helps
Cheers

[1ponders] (Paul) · #6 07-02-2005, 11:34 AM

Robby can you explain "difference blending"?

Robby · #7 07-02-2005, 12:53 PM

Hi Paul,
Take a Master image a place it on Layer0.
Then take the image you want to align and have it on Layer1.
Then change the blend mode to Difference. You will notice the images go black except where there is mis-alignment. Now move Layer1 until all is Black. Images are now aligned. Change the Blend mode back to normat and set to 50% on Layer1. You have now stacked two images together & averaged the result.
Cheers

[1ponders] (Paul) · #8 07-02-2005, 02:05 PM

Ah cheers Robby, thanks. I think even I can do that

Now all I have to do is get more RAM so I don't have to wait 5 minutes after every adjustment I make (usually moving and rotating etc). BTW do you work in TIFF, BMP or JPEG or RAW. If RAW how do you get PS to open them. I've not had any luck so far. I've had to convert them to TIFF

gbeal · #9 07-02-2005, 02:14 PM

Paul,
without wanting to unsurp the good advice from my learned companion, full credit, I seem to favour Registax, and just jpegs. It works for me, and then I tweak with levels in Photoshop.
The slave is good at and understands Photoshop so uses that, but the dummies like me allow Registax to do all the work.
Keep it simple.
Gary

[1ponders] (Paul) · #10 07-02-2005, 02:31 PM

Let me paraphrase that Gary so to see if I'm understanding you correctly. Take or save the images as jpegs then load into Registax (Even if they are slightly out of alignment?) and process. Then to PS

Or load into Registax as bmps or tiff and process and save as jpegs, then go to PS?

Robby · #11 07-02-2005, 03:57 PM

Hi Paul,
I normally set the 300D to Highest JPEG setting and auto White Balance. I have not yet seen any significant advantage in working with RAW's. Just adds about an hour to the processing time!! JPEG's seem fine, and although the purists will argue till the cows come home, jpegs work for me just fine!
Gary has a good point, but I have stuck to Phop for large images. Each to there own... Full credit. I here MaximDL is pretty good too...

.
Cheers

Striker (Tony) · #12 07-02-2005, 04:41 PM

Paul...definetly set your camera to save as JPEG..raw format is just a waste of time......your not going to see the difference between Raw and Jpeg as long as you dont set the JPEG compression up to high.....more compression the smaller the picture file size will be...but dont go overboard.

silvinator · #13 07-02-2005, 05:17 PM

wow, there is so much detail lurking in your shot from what Mike has managed to do with it. Can't wait to see your final version Paul. That's a really great effort for your first DSO. Keep them coming!

gbeal · #14 07-02-2005, 07:24 PM

Paul,
as others have said, I use jpeg all the time.
I started with Raw, but couldn't see the difference, so go with the easiest way now.
So, shoot jpeg, and registax jpeg.
Gary