How to stack correctly in photoshop?

[Garyh]

Hi all ,
just a simple question here for stacking multiple layers/images in PS.
Would I be right to say if I had 6 images I wanted to stack, would I be doing things right if the first frame/background be left at 100% opalcity then the the other 5 layers set to 20% before flattening the image?
I do this as a last resort when registax and deepskystacker does a bad job of it!!
Any ideas on the correct way when doing multiple layers?
Cheers Gary

[iceman (Mike)]

I think the other 5 layers would be set to 16/17% instead of 20, as you want 100% over the 6 layers.

But other than that, yes that's how you do it.

[Garyh]

Thanks Mike, I was pretty close on the right track there.
I used to make say in my example layer1 75%,layer2 60%, layer3 45%, layer4 30% etc but the stacked image didn`t look right too me..so I changed to what I mentioned above.
Cheers Gary

[sheeny (Al)]

If you want each layer to contribute to the final image by the same amount the sequence is:

1 (background) 100% opacity
2 50% opacity
3 33%
4 25%
5 20%
6 17%
7 15%
8 13%
9 11%
10 10%
etc

The formula is 1/n, where n = the layer number.

Al.

[Garyh]

Thanks Al for that information, I shall give it a go!!
Cheers Gary