[solved] adjusting exposure after render

Is there anyway to adjust the exposure after rendering ? with the Physical camera ?
I realise this is one of the benefits of the Physical Camera, being able to set each camera to a different exposure.
However I find the new Perspective Correction is better and easier to use than using the standard camera with correction modifier.

Press 8 > Turn off Exposure Control

You can now use the Corona VFB Exposure instead

Aaah okay its under the environment and effects, got it.

Thanks