Hi

 I am experimenting fiddling with my pics in Adobe's Photoshop Elements 6................I can stack images.......but I don't how how to subtracts the Darks that I have taken.......could someone give me some advice please?

 Many thanks,

Nick

try deep sky stacker instead

Thanks for that, I will give it a try.

 Does anyone else have any tips?

 Nick

I'm fairly new to using Photoshop Elements 6, so I'm just learning it myself.   Anyways, I'm not possitive, but I don't think the stack command is the same as stacking images to compile into one like you would in Registax or Deep Sky Stacker. I might be wrong but I think it is to stack images to organizing them like you would a collection of prints into a pile of pictures. Placing them into a pile with only the top image showing.  
You want to use either Deep Sky Stacker,  Registax to register, align and compile a stack of individual frames into a single image. 
I use Deep Sky Stacker for Deep Sky images Registax for planetary and lunar images.  Deep Sky Stacker will handle the darks, flats and bias automatically and is friendlier on your system resources (CPU and Memory). It makes it much easier on you.

Other suggestion; since you're using Photoshop Elements 6 buy a Noel Carboni's Astronomy tools for photoshop.
http://actions.home.att.net/Astronomy_Tools_For_Elements.html 

And get your hand on a copy of the book called "Photoshop Elements 6, The Missing Manual".  It's a good book to help you along with photoshop..
 

Have A Nice __________

 Here is a link to a friends site with a tutorial on Photoshop editing of astro images. There is a way to get rid of sky glow and noise without darks. It is not too Firefox friendly so you may want to use I.E. if you normally use F.F.