C-41 films. Overexposure really beneficial?

[pentaxpete]

I shall have to 'dig out' the remaining outdated VPS III I have in 'fridge ---
1987 dated VPS III rated 40 ASA in my Mamiya C220
Arches 1 by Peter Elgar, on Flickr

Crocus 1 by Peter Elgar, on Flickr

 

[Mr Bill]

Before I go on, have a guess at how you think the films aged (up to a year or so after the expiration date).

I guess not too much interest in this, but since I carried the topic on I should answer. In our mass market portrait chain, a particular Kodak VPS III emulsion, from when it was NEW, until it was PAST EXPIRATION date, DID NOT CHANGE sensitometrically. The sort of thing you read about - that it slowly changes as it ages - DID NOT HAPPEN, with respect to what a photographer or lab can see.

Upwards of 5 or 10 thousand sensi wedges, covering beyond the expiration date of dozens of complete emulsions (the entire emulsion runs were reserved for us) over the years conclusively supported this.

Portra 160 NC showed the same sort of results, but I can't speak in great depth as I was not intimately involved. We eventually cancelled our new-emulsion screening program, as the Portra film was so consistent. I should also point out that my Portra experience is now out-to-date by roughly 8 to 10 years. So I can't be certain that the same conditions still hold (but I'd probably bet a lot of money that they do).

I shall have to 'dig out' the remaining outdated VPS III I have in 'fridge ---
1987 dated VPS III rated 40 ASA in my Mamiya C220

Cool. This is so far out of my experience that I would have had no idea.

 

[BMbikerider]

I bracketed Ektar 100 and had a pro lab develop and provide a contact print. While I could scan all and get decent results, I notice that there is a shift in color among the different exposures. It's not great but enough if you need color fidelity.

I can agree with this. Manufacturers will have gone to great lengths to determine the exposure required for the optimum reproduction. Why some folk feel they can do better than the manufacturers is beyond me, unless it is of course the exposure meters fitted to their cameras is incorrectly calibrated and they feel they need to go +/- to get the exposure that suits them. Or are they so uncertain of the reading given by a meter they feel they have to compensate in case they miss a good photograph.

 

[RPC]

Shouldn't really be much, if any, noticible shift in color with normal bracketing overexposure, but probably would be with underexposure. A noticible shift in color with exposure changes will always result if there is crossover (characteristic curves aren't parallel) in either the film or paper, which can result due to improper processing or the film is shot at the wrong color temperature.