Stacking for noise reduction

Hi Folks,

Not being an expert in Photoshop, I'm trying to figure out the basics.

I've heard that, if one takes a number of identical pics and "stacks" them
in Photoshop, one can obtain an end image with less noise.

I'm wondering what steps are involved in this process so I can ask my son to
give it a try.

Appreciate all the help I can get.

Thanks,
Dudley

 

In this example, they show a high ISO shot but why use high ISO if
you're on a tripod? I don't think this technique is very useful in
normal photography... maybe if your camera only does 30 second exposures
& you've got something very dark. Astrophotography isn't normal photography.

--
Paul Furman
www.edgehill.net
www.baynatives.com

all google groups messages filtered due to spam

 

In what context, Dudley? You might find dark-frame-subtraction (which
is a built-in feature of some cameras, or can be done manually) helps
also, depending on what he is shooting.

Registax is often mentioned by astronomers, but I haven't used it, only
dark-frame occasionally...

 

The technique is a bit different, Paul, but my A720 is a bit noisier than
I'd like, even at 100 ISO. I thought I'd try the technique to see if it can
improve the quality of some of my pics. Since I do a lot of low-light work
without any movement, I'm hoping that stacking will give me quality closer
to that of a DSLR.

Take Care,
Dudley

 

Thanks for the links, Alan. They are just what I was looking for. Your
Google query was much more presice than the one I tried and yielded much
better links.

Take Care,
Dudley

 

If you are tripod based you may get the kind of results you are looking for
with HDR processing in a program like Photomatix--the Photoshop version
leaves much to be desired.
It is best to use identical images obtained with different exposures, at
least 3 but it can be more depending on your desires/experience.
You can use Photomatix to process as HDR images differently processed
versions of the same image, particularly useful if you are beginning with a
raw image, probably useless if you are using in-camera mutilated jpegs.

 

If you just want to do stacking and do it easily then try a little program
called "registax".

Cheers.

Pete

 

Take Care,
Dudley