Postscript
Having spoken to the guy who did my EOSM conversion, to 720nm, it looks like the EOSM sensor has an asymmetry that results in colour cast down the left hand side.
Apparently the EOSM3 has this as well. Not sure why? Tolerancing in the glass maybe? You see less of the effect if you convert to a full spectrum filter, ie less glass.
If you process in B&W you won’t see it.
If you process in false colours you will, especially if you push the colours, eg with a heavy debase.
You can reduce/eliminate the colour cast in LR, but it will require a bit of extra post processing.
Just a warning if you are thinking of using an EOSM for IR imaging.
Cheers
Garry