How can put background in the image while not affecting render result?

[gandhics]

I want to see my render against plate.
I put the image as screen space environment map and turn on all overrides in Scene Environment rollout.
But, the render is still getting GI from env map.

[pokoy]

You probably have put the map into the environment slot, this will create GI if Corona is set to use 3dsmax environment. Put it into the background override slot in the renderer settings instead.
You can still use the environment slot for the background, for example if you need the viewports to show it, but you then need to set Corona to use its own environment, you'll find this in the renderer settings tab too.