What if i render as RGBA when its no transparent background in the scene?

Hi. My question is What if i render my scene as RGBA instead of RGB when its no transparent background in the scene? It will somehow affect my rendered image or post processing abilities?

My understanding is no it will not nor have I seen any change in my work. I have read it will cause longer render times but there to I haven’t personally noticed any real difference.

Main thing is extra file size as it record the alpha channel - by choosing rgb instead, you should see a small difference.

Thank you. Thats probably one of the reasons why my scene renders so long…

No, it’s not. The effect on render time is negligible. You refreshing a web page during the render is probably going to effect your render time more. Even the disk space effect is pretty small for most formats, because they’re compressed. Even with lossless compression, an entire channel with a single value will compress down to almost nothing.

And I agree with you.
RGB or RGBA it’s a choice at the time of saving the render, so it shouldn’t affect rendertime. If you save RGBA an image with no transparent background you’ll just get an extra channel (alpha) plain white, very light on disk