Tmax 100 Dichroic Fog

[IanMazursky]

Hi Keith,
I would love to try some other developers but the PhotoTherm was designed a bit differently then a Jobo ATL.
Its not as flexible when it comes to chemistry and times. A lot is pre programmed.

PhotoTherm has a table that comes with the machine for most films but its only for Tmax dev 1:5.
Most of the times are not the standard published ones for rotary tube but they work for the combo of film, chems and times.

Phil,
Thanks for the suggestions. I need to keep the same densities in the negs that come out of the processor.
I am using them to help calibrate my LVT Rhino. The LVT is extremely sensitive to processing.
Ill try to experiment with Tmax RS soon. Hopefully i can match what i get from the regular Tmax dev.


I did some more research on the net and found that a acidic stop bath might help.
The PhotoTherm uses a water bath between the dev and fix. Maybe that could help to stop the Dichroic Fog?
Ill try to mix up some kodak indicator stop bath and reprogram the machine.
Hopefully that works.

Thanks to everyone for the suggestions.

[Robert Hughes]

But, what if I stick with Tri-X? Will I suffer from Trichroic fog?

[percepts]

But, what if I stick with Tri-X? Will I suffer from Trichroic fog?

No you'll just be very tri-ing

[IanMazursky]

Hi Robert,
Nope, TriX is fine. Ive processed a lot of it from the same Tmax dev tank and they are 100% OK.
Its seems to be only Tmax 100 that causes the problem.
Of course it has to be that Tmax 100 is giving me problems and thats the only film that Durst recommends for the LVT.
Some days you just cant win.

I was also thinking about what Phil said about the water quality. While our water is fantastic, i wonder if the PH changed.
The PhotoTherm uses a water bath as a stop, maybe its not acidic enough in the winter.
I should get a PH meter or find those little strips from my old chemistry sets and make a running record.

I know some of you are wondering why i don't use distilled water, the PhotoTherm requires the metals that are naturally present in tap water to run.
In the tempering chamber (a lab stir plate/heater with a stir bar), it has a number of metal wire electrodes at different heights that sense the water level.
It uses them to tell the pump when to stop pumping fluids and when the proper level of fluid is reached for the different sized drums.
I even bought one of those home water distillers off of ebay, it works but i cant use it for the PhotoTherm.

[PViapiano]

Ian...did you know that PhotoTherm will make you a new custom chip with times and temps for basically the return of your current chip plus shipping?

[IanMazursky]

PViapiano, Thanks for reminding me, i knew they could make a custom chip but i didn't know the second part.
It might be where i have to go.

I just tried using an acid stop and it didn't help so Tmax RS is next.
Im going to call PhotoTherm in the morning to see if they any more recommendations.

[Sal Santamaura]

...While our water is fantastic, i wonder if the PH changed...

The latest water quality report for your supply is here:

http://nyc.gov/html/dep/pdf/wsstate08.pdf

Note that, since the Catskill/Delaware and Croton Systems are blended, your tap pH runs from 6.5 - 8, with an average around 7.2 (98.3% of delivered water comes from Catskill/Delaware).

I hope those data will keep you from having to do your own measuring. As a former New Rochellean, I've certainly missed the water quality since leaving there for southern California 33 years ago. Here, we simply describe ours as "crunchy," just like the air.

[Brian Ellis]

Is it just the regular Kodak T-Max developer that can cause dichroic-fogging, or can other brands and types of commercially available developers do so as well?
I don`t use T-Max developers, I`m just curious to know.

I used D76 1-1 almost exclusively with TMax 100 and never had any fogging or similar problems. Also used Rodinal once in a while and another brand - LPN? LFN? - something like that - without a problem. John Sexton uses TMax RS but IIRC he dilutes it differently than Kodak suggests or does something else differently, I don't recall exactly what.