Related question... If i'm running C41 5 days a week, is it advisable to run control strips? I am not sure if that's necessary for non-replenished developer systems...
Hi, control strips are generally considered to be mainly for replenished systems, because there are more things to go wrong. Say, for example, a replenisher pump fails so that you are not getting developer replenisher. A control strip would show weaker development, and you'd start troubleshooting and probably find the bad pump right away. Obviously you don't need to worry about this sort of thing if you don't replenish.
But a second use of control strips is to prove that your process is functionally "within spec." I'm thinking you plan to do some commercial processing, so maybe you want to know if it is, one way or another. A lot of people here would say no need - just use the correct time and temperature, you'll be fine. But what if your temperature readings go on the fritz - say you're 2 degrees off; how would you ever find out (or do you even care)? Or perhaps you got a shipment of chemicals that are sub-par, or are somehow damaged. How would you find out? If you have control strips, you test process one, read it, and you know if you're ok or not. Of course there are other ways to check on this. You could shoot a test roll, then split half off to a lab that you somehow know is in spec; you process the other half yourself and compare.
So I'd say it largely depends on how finicky you are about things, and how reliable all of your systems, including chemical suppliers, are. If the end result doesn't matter much then you don't have to be so finicky. But if you're trying to do higher end work then it probably behooves you to know how your processing stands. Imagine being in the position of having a high-end wedding shooter come to you saying, "My last wedding, I split the film between you and XYZ Lab - your film is not as "punchy," what's going on?" It would be nice if you could look at your records and say, "hmmm... my test strips were right on the money that day, must be the other guy who is at fault."
Sorry there's no real easy answer to this.
