yes thats what I’m doing, but I leave the green alone since the lens is usually optimised on green
the optics comp works best on diagonal scaling but is still not quite right since the idea is to effect a refractive index change/displacement rather than a barrel/pin correction
maybe I could try a displacement map using a bw grad – but I will have to do it in 4 halves – top, bottom, left , right
unless someone has the finger on the pulse for this sort of thing