why?
It is probably not supported by the render pipeline. Which one are you using?
Under HDRP, I have the option available.
May I ask what feature of the TextureSampling input type are you using ?
It is not a common use case, thus is probably one of the feature that receives less attention compared to the other ones.
I use TextureSampling just because it support the alpha(Gameview not).
Im in URP, and I found that in my case. The recorded images have alpha channel but the check box does not show up.
In your Unity Docs, it said that if I do not use Game view and jpeg format, it should have the option of caputure alpha or not.
SO is it a bug?
I don’t think it is a bug (that the UI does not have an option). There might be a bug that there is an alpha channel in in the output PNG (containing the wrong data potentially)
URP does not support rendering of alpha from what I can tell, so this option cannot be supported until it does.
ok so the Doc of the Renderer aims on hdrp.
In my case I can export image sequence with alphal channel in unity urp. It does but not good.