Zone VI Compensating Developing Timer
I was looking at the Calumet site today and I noticed they are selling the Zone VI Compensating developing timers again. I thought they had quit makeing these. Maybe they saw all the interest in used ones and decided to go back into production with the timers.
Zone VI Compensating Developing Timer
I always liked the compensating metronome. Not sure if that's still made. It makes printing so easy ... step on the pedal for light, take your foot off when you need to stop and grab another tool (or a drink) and just count clicks. Helps keep burning and dodging consistent from print to print also. only drawback is you have to turn the music down. and after 4 in the morning or so it can be challenge for me to count too high above 15.
Zone VI Compensating Developing Timer
Paul - this post is regarding the compensating development timer, not the enlarging timer. Mike - I got my timer on the used market (and they do command high prices). Sure glad to hear they may be making them again. Have you confirmed that they really are making them, and it's not just a hold-over on their website? When I tried to get one from Calumet, their website still listed the timer even though it was not available new from Calumet.
Zone VI Compensating Developing Timer
Sorry, my misunderstanding.
Question about the timer: does it allow you adjust the curve of the temperature/time relationship, or does it make the (wrong) assumption that all developers respond similarly to temperature change?
I have a lower tech, foolproof solution that can be adapted for any developer. If anyone's interested I can post intstructions on how to do it. Maxim Muir published it in his black and white newsletter a few years ago.
Zone VI Compensating Developing Timer
"Question about the timer: does it allow you adjust the curve of the temperature/time relationship, or does it make the (wrong) assumption that all developers respond similarly to temperature change?"
I don't know if there are any internal trimmers that someone familiar with the circuitry could adjust to accomplish that, but it has no such external controls. Given Fred Picker's material choices, it's probably set up for Tri-X in HC-110.
Zone VI Compensating Developing Timer
From the outside, there is no way to adjust the curves. Perhaps there are some "pots" or something if you opened up the timer. Not sure.
However, I took some data and did a comparison with the curves on the Ilford site for HP5. For each one degree F difference from that temperature specified by the Ilford curves, my timer's compensation would be off by approximately 3 seconds. (With the timer turned to the film setting, versus the paper setting.) I had no way to evaluate the paper setting of the timer.
Assuming that the Ilford curves are accurate, that's not too bad. I use my timer for all film and paper development. Versus relying on the timer for large differences in temperatures, I try to stay close to the specified temperature using a water bath and let the timer compensate for any small variation in temperatures thereafter.
Zone VI Compensating Developing Timer
I have owned one for years. The timer is set up for Tri X and HC 110. There is no way to adjust it. Have found it lent alot of consistency to my paper developing too.
Peter
Zone VI Compensating Developing Timer
There is a way to adjust it, but you have to open it. If you do open it there are two screw adjustment wheels, one on the far right and one on the far left about 1/3 down from the top of the circuit board. The right hand adjustment, adjusts the slope of the curve or, IOW the percentage change for each degree of change in temperaure. Leave this one as is, it is about right regardless of developer. The left one takes care of the "set" temperature, this is the one you want to adjust if you want your "normal" temperature to be higher or lower than the 68 ºF that is set to. I adjusted mine to read 74 ºF as the base temperature .
There is nothing to it, BTW make sure you unscrew only the screws in the corners, if you do the middle ones, you will loosen the circuit board.
Zone VI Compensating Developing Timer
The curve depends on the developer agent used. Metol has a diferent curve than hidroqinone.
I have used it with D-76 and it gave me no problems. What will be neat is to try to put the termistor
(sensing probe, I think it was 5K ohms) inside a Jobo tank with a sort of rotating external contacts to send the info to the meter.
Jacques
Zone VI Compensating Developing Timer
I know the curve depends on the developer, but the setting they use is pretty much average and it is a good reference, unless you are willing to open the gizmo every damn time you change developers.
I beleive you meant metol has a different curve than phenidone as most developers are a combination of these two with Hydroquinone. You would be surprised how close the curves are once they are mixed.
Do you have a Zone VI timer?