edge density/stain issues with tmy, pmk, and jobo reels
tmy-2 in 120 format shot with two different Pentax 67II's (the cameras aren't the issue), the film isn't the issue either
jobo cpp-2, on speed 4, bi-directional rotation
2 min presoak as I do with all films up to 8x10
jobo 2500 series tanks
plastic reels (one roll on each reel)
1L fresh pmk for first half of development, fresh 1L for second half
30-45 second water stop bath (I never use stop bath)
4 minutes in homebrew fixer (Agfa 304 rapid fix)
10 min wash
distilled water final rinse
tmy-2 in 120 format shot with two different Pentax 67II's (the cameras isn't the issue), the film isn't the issue either
I use the exact same setup for E6 and c41 and never had an issue of any kind.
This isn't the only time I've seen this happen but I'm looking at previous rolls of tmy-2 and I can't find any defects. The only roll I can find similar density issues with is a roll of plus-x I soubet in tmax 1+4 but the density is outside the exposed film area.
The added stain/density runs lengthwise on top and bottom of the film for the entire length of the roll. It appears to be about 1/16" wide and 1/4" in from the edges of the film.
PMK does a wonderful job with TMY in trays (sheet film) and Jobo etc hand-inversion tanks (roll film). But it is not recommended for rotary
processing. Too much agitation, oxidation, etc - and this might easily explain your specific problem (or it might not, but let's call it one of the
"usual suspects"). There are other pyro tweak made for rotary processing. If you think you absolutely have to stay with PMK, there are a few minor tricks you could try: try adding a tiny amt of 1% EDTA to the developer to help flow; 2) use the lowest RPM possible; 3) have a fill tube
to displace any oxygen in the tank with inert argon gas.
I've been using pmk with rotaty processing for 10yrs and i've heard "it's no good" plenty of times. It works just fine. Bob Carnie has been using it this way for a lot longer than me, w/o issues. I use edta as well. As i said, Nearly all of my film gets souped in pmk so I don't think developer choice is causing this issue.
Last edited by wildbill; 05-01-2014 at 07:58 PM. Click to view previous post history.
I get flow marks like this with the same equipment and film, but with Xtol. I think it is something that randomly occurs and cannot be permanently fixed.
When you pour the developer into the tank, assuming you are using the lift, it should be spinning at maximum RPM's for the first 30 seconds. Then reduce to the slowest speed for the duration of the developer time. Have you been putting the reels in the Photo Flo solution, dried Photo Flo on the reels could also cause this problem.
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I have always keep it on speed 4 whether or not I'm using an expert drum with 8x10 or 2500 series with 120. I did another roll of tmy tonight (that had to be pushed to 1600) in tmax 1+4 and it came out perfect.
The damned Jobos are revved up like heck, so I don't know how in the world anyone could call results ideal. The first thing I'd do with one of
those things is pull the tiny gearmotor and berserk speed control and install something more serious.
... So how do I (specifically) know that PMK and rotary processing aren't all that great?.... Sure I got printable results. But my PMK negs got a
lot better when I quit doing it that way.
I'm getting better negs and prints with the jobo than I was with other previous methods. There's more than one way to skin a possum. I'm more interested in what is causing this random issue.
Anybody have any other ideas?