Custom Bit Depth

Use the posterize command.

But how are you planning to save these images?

I am unsure. What I am currently thinking is that If I can covert a copy of image into 12 bit I will then copy those pixels back into the original image, with their new color information. The software I am using these images in (Director)is not the problem, it is the display that they will be shown on (12 bit screen). I am trying to create 24 bit images that only use colors found in the 12 bit pallete. What do you think?

Why not just duplicate the file and convert the duplicate by going under Image>Mode>Index Color. This will give you an 8-bit palette (256 colors) which should be fine for a 12-bit screen.

It's been a while since I've used Director much. I'd do the images with an 8-bit palette. You'll get better performance than using a 12-bit or 24-bit palette. I believe director would 12-bit images as 24-bit anyway.

You only need to convert one image to 8-bit. When you import it into Director it will also place the palette in the cast member list. You can then use this palette to transform any remaining images.

The best app to use for this is actually debabelizer. It can analyze all of your images and create the "ideal" palette to use on all of them.

Also don't forget to set your stage properties to use the new palette.

--Wow edit is back. What's old is new again.--