Everyone says to check every piece of equipment before shooting an event. I recently shot a family member's graduation party, with a Sto-Fen "Omni Bounce" cover on my auto flash, my first use for the cover. Figuring that it was inconsequential, I didn't check it ahead of time.
The cover was causing considerable light to scatter back to the flash's photocell. (Later I found on the manufacturer website a recommendation to always have the flash tilted up 45 degrees when using the cover, to prevent this). The result: very underexposed negatives. As I noticed late in the event that the flash seemed a bit dim, I had a feeling this would happen, and processed only one roll to see. The others are being pushed 1.5 stops--the most the local lab recommends pushing Portra 160--but it's likely that they, too, will still be underexposed.
When I put the first (normally processed) roll on the light table, I could still see people, faces, etc. They were faint, but I could see them, more so than in an overexposed area of a chrome. It helps, too, that these are 6 by 6 negs, so loss of high-spatial-frequency detail doesn't matter as much as for 35 mm. Is there a standard way to recover these images digitally? (Fed up with paying out the nose for low-res and oversharpened scans from good film, I am buying a scanner.) Should I give up on color and treat them (in the computer) as though they are black-and-white? Should I try to print them optically as black and white, then scan the optical prints? Should I learn to print C41 myself--I've only done black-and-white--and try the "Anderson process" of bleaching and rehalation (and then scan those positives and enlarge)?
In short, does anyone out there have any tips for recovering something useful from underexposed C41 film?