How to align multiple stacks

[Didge]

Hi,

Ive created 10 stacks, each from a single astrophotography session of the recent lunar eclipse - 1,699 images all together.

The images in each stack are aligned, but the stacks aren't aligned with each other because I had to move my telescope to avoid trees as the moon moved across the sky.

I've copied each stack into a single document as groups in the layers panel.

Now I want to align the 10 groups with each other - what is the best way to do this - without having to realign ALL the images ?

Also, I'm trying to view the 'Range' for all the images, but selecting the 'Range' for one group draws its range over the top of all the groups displayed at a lower level in the layers panel.

Is there a simple way to display the Range of all the groups combined ?

Many thanks,

Gary 

[Didge]

I should have mentioned that all the images in each group are pixel layers - no vector graphics or text etc.

What I'd really like to be able to do is simulate blend modes on layer groups, without having to rasterise them.

That way I could treat each group as a layer, and used the 'difference' / 'subtract' / 'exclusion' blend modes to align the groups manually.

So for example, you could apply the 'Maximum' stack operator for each layer, and then the 'Difference' blend mode to determine the difference between each group, and then use the nudge function to shift one group to match the other at pixel level.

Is this possible ??

Gary

[walt.farrell]

I'm not aware of any way to align stacks like you've asked about. You might need to export each stack as a new TIFF file, and then align the 10 TIFF files.

[Didge]

Hi Walt,

Yes, that would work, but I need to preserve each image because I want to align individual images in each stack, then align the stacks, then export each separate image to composite into a movie.

It seems that (Live Stack Groups) functions differently to 'vanilla' groups ...

I found I can get the result I want by using the 'Group' command on each Live Stack Group to enclose it in a 'vanilla' group.

Then the blend modes work on the enclosing group.

Then I select the entire group in the top layer, and 'nudge' that pixel by pixel until the groups line up exactly.

Regards,

Gary