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jon.leatherwood
4-Oct-2011, 09:54
I've been working in the darkroom for a good 40 years but am totally puzzled by my results with Pyrocat-MC.

I'm using TMAX 400 4x5, and it's all coming out under-developed (using the edge marking as a guide). I've mixed the developer in my tap water (filtered well water) as well as bottled drinking and distilled water, with no change in result. Time/temp is 10 mins in tray at 75F, shuffing usually two sheets, continuously for the first 30 secs, then at 30 sec intervals. I'm using TF4 fixer w/o stop bath. Everything looks a stop or two under.

I just shot and processed a test with a different meter, scrupulously checking exposure, bellows extension factors, etc etc, and it's just like all the others.

When I mix up my dev (6cc + 6cc + 600ml H20) it's slightly brown in the tray, and after I've finished developing (after 10 mins) it's turned wine red/purple, which I gather is normal. The code on the bottles is 120.

What am I doing wrong?????

Thanks

Richard Wasserman
4-Oct-2011, 10:23
I think you might be under-developing. Depending on the range of the scene I process TMY-2 which I rate at 250 EI for 18 minutes @72, agitating every 3 minutes. I enlarge with a color head.

domaz
4-Oct-2011, 14:10
I have to add a bit to the published times for Pyrocat-MC as well. Don't take the "standard" development times at face value.

Jay DeFehr
4-Oct-2011, 16:53
Jon,

Edge markings are not a very reliable indicator of proper development. Have scanned/printed your negs?

ic-racer
4-Oct-2011, 17:14
I just shot and processed a test with a different meter, scrupulously checking exposure, bellows extension factors, etc etc, and it's just like all the others
Was that a Zone 1 test shot? Did it come out to 0.1 log D?

Increase development by 20% and re-assess. Keep increasing development time until they are printable on your favorite paper. If you use multigrade paper, there is a lot of leeway.

jon.leatherwood
4-Oct-2011, 20:13
I checked in with Sherry at Photographer's Formulary and learned that the batch number on the bottles dates from two years ago - she thinks that's the problem. How time flies ...

I'll get some fresh juice and reassess.

Many thanks for the input.

Cor
5-Oct-2011, 07:54
Jon,

If it's mixed in glycol, it should be ok. Stock colour changed to a very deep brown/black, but with no adverse effects (checked with the Guru himself..;-)..) It seems that the metol is causing the colour change a deep brown with no adverse effects on development.

Best,

Cor

Bob Farr
5-Oct-2011, 11:40
In addition to the above, are you pre-soaking the film?? And do you have enough developer so it does not become exhausted during development??

Good luck, let us know what you find out.
Bob

evan clarke
6-Oct-2011, 16:18
My normal time for TMY in MC is 14 minutes with continuous agitation...EC

evan clarke
6-Oct-2011, 16:19
Also, at 1+1+100 ANY fixer residue will kill development.. I am using 1.5+1.5+100..

sanking
6-Oct-2011, 16:53
Also, at 1+1+100 ANY fixer residue will kill development.. I am using 1.5+1.5+100..


Because of the very small amount of developer used in Jobo (and BTZS type tubes), and the relatively high pH needed to fully activate pyrocatechol, any acidic residue left in the tank may reduce the pH of the working solution, thus making the developer less energetic.

BTW, I also recommend long term (more than six months) storage of both Stock A and Stock B, in glass containers.

Sandy King

zoneVIII
11-Oct-2011, 13:00
my normal time for tmy2 is 18minute @21C intermittent agitation 10s perminute, EI 320, pyrocat MC in glycol 3 years old

Jay DeFehr
11-Oct-2011, 13:38
Wow! These times seem very long to me, and on the order of 2-3X my times with Hypercat II, which contains no secondary developer.

John Berry
11-Oct-2011, 23:06
If your doing tray developing as you indicated, your agitation is going to be a problem. You need to develop a protocol that is based on continuos agitation.