[RB (Andrew)]

Originally Posted by Aster

Should have been clearer with my question.

All 4 images are as originally stacked, no levels or curves or anything.

Yep we realise that and that's why the two raw stacks are darker, it's what Jase was talking about with the bit depth stretch etc.
"Going from 12-bit to 16-bit will not result in any data scaling, but the image will probably look rather dark until you stretch it."

Originally Posted by Aster

The main thing which had me puzzled was why the change in the background hue/colour in the converted RAW to TIF Stack ?

Meaning, I converted the Original RAW frames into TIF before stacking in DSS.

When you convert the RAW's to tiff and then stack the tiff's you end up stacking the stretched converted frames.
Not what you want to happen.

Originally Posted by Aster

Andrew, you used the converted RAW frames Stack, the one with the different background, to fiddle with. I found that harder to get the right balance in CS2 then the original RAW stack.

So, it is best to stack the original RAW frames, not convert them to TIF and than stack.?

Thanks to both of you

Yes I used this one because it had more range, don't forget these images have been down-converted for the web so I chose the jpg which had more room to play with before clipping.
Yes it's best to stack the original RAW frames and not convert them to tiff first then stack.
The final RAW stacked file will be darker but this will give you a bigger dynamic range to manipulate.