Just a dumb thing to do but today I did some still life work with 4x5 and 120. With 4x5 I used Portra 160 and calibrated the light meter to suit. Then I switched to my Mamiya with a roll of Portra 120 400 forgetting to alter the light meter settings. To add to the dilemma they were 30 second exposures in low light. Oh shit, I had spent 6 hours labouring away on getting everything right, well almost everthing as it turns out.
It wasn't until I was packing up my gear I realised the stuff up. Half the 120 film was already exposed at the correct levels. Can the overexposed shots be rescued in the developing or is the gap too great? I am happy to take a guess and cut the film where I think the overexposed shots start to develop it separately to the rest.
I use Tetanol Colourtec C-41 solutions for developing.