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daz1761
09-26-2011, 10:21 AM
Hi

I am about to render my scene but I would like to be able to composite my own background using adobe after effects and I was wondering what image format to save it in?

I normally render a frame using a 24bit TGA format, I was thinking of rendering my scene using a 32bit TGA format because of an 8bit alpha channel, but I got confused when in the render globals tab when I come across "save alpha" as well as "save rgb"

Thanks in advance

nickdigital
09-26-2011, 10:27 AM
I think those options are if you want to save out the RGB and alpha out as separate image sequences...but I could be wrong.

If you pick TGA32 or PNG32 you'll get a render with the alpha embedded, that's most likely what you want.

daz1761
09-26-2011, 10:43 AM
I think those options are if you want to save out the RGB and alpha out as separate image sequences...but I could be wrong.

That does make sense, so if I did want to do that would I still select 32bit TGA?


If you pick TGA32 or PNG32 you'll get a render with the alpha embedded, that's most likely what you want

Excellent, will stick to that in future, just need to sus out how to stitch them all up in premiere pro correctly

Thanks :)

nickdigital
09-26-2011, 10:57 AM
That does make sense, so if I did want to do that would I still select 32bit TGA?


Not sure, try it and see what happens. :D

wrench
09-26-2011, 04:17 PM
No, you can save in whatever format you like, even if it has no built-in alpha if you do that, but then your compositing software needs to take separate alpha files into account.

Also, try PNG-32 as your format. TGA is not compressed at all so the files can be very large, whereas PNG is, but losslessly, unlike JPEG (JPEG can't have an alpha either).

B