I have a Fuji 5l kit, that will have reached its 6 weeks recommended use in about a week, and i've only processed about half the intended films. I've heard people saying they have used the developer beyond the date recommended.
My question is, should i add extra time to the developer process, and if so by how much. can anyone lend me their experience if they've tried it.
Normally you would add time as you go anyway, so that the development time for films 5 and 6 is longer than for 3 and 4, which is longer than 1 and 2, etc. I've used Agfa developer which is a couple of weeks older than recommended, and did not add any extra time to compensate for its age, and I would recommend that you do the same.
already doing that(my kit states after 24 films before changing times and i'm still only on 3' 20"); my question was more about how old time-wise, than the amount of time's its been used.
I keep a few rolls exposed with brackets of the MacBeth chart. Cut off a few frames from one of these test rolls and process it in your chemistry to verify its performance. This method is a lot better than taking a chance on failure on important film.