Turntable bug? Frame around object

[Nerowulf]

Hello

I was testing the turntable, because I want to have a spinning model, where there is a movie behind it. Therefore I though I could do a turntable and turn off environment and shadow, and save the pictures as TIFF.

So I tested this on a simpler model, to cut off some rendering-time.

Everything went well, except for one thing. Around my model, there is a white line. I don't want it. Removing it with help from Photoshop would work, but no way I will do that to 100 frames.

[guest84672]

Did you render the images with "alpha channel" checked?

[Nerowulf]

The "include alpha" yes.

I tried now without it checked, and then I got a white background. I don't want any background. What does the alpha do?