Alpha in rendered pictures


(tmohr) #1

Hi,

i’d like to render pictures and export them as TGA with ALPHA in them.
How can i enable this? The background is always black.

Best regards,
Torsten.


(VelikM) #2

Click the ‘RGBA’ button (in the Display buttons window) to have the render include the alpha channel. The app you view the pic on has to support alpha.


(theeth) #3

It is always a good idea to use Key instead of Sky (or even Remul). Look for the Key button at the bottom of the Display Buttons window.

Key rendering will mess the RGB channels for halos, but the Alpha channel is made to compensate for this.

Martin


(Jamesk) #4

If you plan to composit stuff in the sequence editor, it’s recommended to use ‘Premul’ for the alpha. At least that’s what the Blender Guide claims the sequence editor expects. ‘Key’ works best if you will composit in photoshop or some other 2d app.


(tmohr) #5

Hi,

ithanks for your hints, but still when i save a file and load it in gimp
it has no alpha channel. Also the info tells me it is a RGB file.

I selected RGBA and tried “Premul” and “Key”.

Hmm, what can be the problem? I save the files as uncompressed TGA.

Thanks for hints,
Torsten.