Dark Gradient on 120-Tmax-400 in Clayton chem.

<p>I processed 5 rolls of film this weekend using Clayton F76 Plus developer concentrate and Clayton Archival Fixer concentrate.<br>

For all 5 rolls volumes, ratios, and temperature were dead-on label specifications.<br>

Previous uses of this combination with 120-Tmax-100 gave excellent results using 12 minutes @ 1 to 9 ratio at 68°F and then 4 minutes of fixing followed by 10+ minutes of rinsing in the developing can. Agitation of 5 bump-turns of the agitator stem every 30 seconds for both processes. No issues.<br>

This time, 3 rolls of Tmax-100 came out fine, but 2 rolls of Tmax-400 developed at 8 minutes, per label, came out with purple residue, all other steps and times the same as previously specified.<br>

The residue seemed to mainly be in areas of lower exposure, but I also noted it was in a gradient from the bottom of the tank to the top, going from lighter at the bottom to heavier at the top.<br>

Note that my camera is an M645, so the shutter moves vertically, but the gradient is horizontal, so it is probably not camera related.<br>

Rinsing consists of a funnel placed into the central column of the tank and a low flow stream of tap water running into it, so it does rinse from bottom to top. 10 minutes. Then 2 more minutes of the tank filled with Clayton Archival Wash (1:42) prior to a final fresh water rinse and then distilled water with a rinse agent prior to hanging.<br>

Any suggestions as to what I am doing wrong? Does 400 film need longer fixing times? Is my rinse to gentle or too short? I'm at a loss to understand the differences.</p>

<p> </p>

<p>Re-fix the affected films and see if it cures the problem. If it does, look at your method and see where you went wrong.</p>

<p>T-grain films, like T-Max, take a long time to fix. But also, T-Max has a lot of sensitizing dye (the stuff that makes it red and green sensitive) and it takes a lot of fixing to get it out. And yes it makes a pink/purple look if you don't get it out.</p>

<p>As above, refix and rewash, and it should clear.</p>

Something similar happened to me. Since then I presoak the film again and again until I get rid of the dye. It does tend to

be darker at the bottom which might explain your gradient. Just in case I also overfix, but I think its the dye.

10m rinse at the end is too little I think. I would say 20m at least.

<p>Hello everyone. Check your hypo with a snipet of film before doing a session. If it takes over 3 minutes to clear, consider replacing the hypo. I have found most of my Tmax films require 2-3 times the clearing time to eliminate the purple/blue dye used in these films. I use a non acid hypo religiously. You might also consider using a "big pinch" of sodium sulfite in the first post hypo wash, if the film appears clear on the emulsion side, but has the blue dye still present. If your developer has a generous amount of the ss, the blue dye usually comes out in the presoak or developer liquids. Bill</p>

<p>Thanks to all for your help. Based upon the accumulated responses, I've done the following with excellent results:<br>

1. Pre-rinse the film in the developer tank (Thanks Andres)<br>

2. Normal developing time per chemical manufacturers schedule for the Tmax. Switched back to tank inversions every 30 seconds instead of the tank cam bumper.<br>

3. Stop rinse of 50% distilled vinegar (2% acidity)<br>

4. Water rinse (short)<br>

5. Fix for 10 minutes, again with tank inversions every 30 seconds.<br>

6. Water rinse for 25 minutes <br>

Results look great! No loss of contrast or detail, uniform exposure.<br>

I was not concerned with hypo strength, I always mix a fresh 20 oz. from concentrate, and it was a newly opened bottle.<br>

For anyone interested, I've put together a small excel sheet that allows me to get my 68 degrees in the developer every time. I live in SoCal and stored materials are almost always around 76-82 deg., even with the AC on.<br>

1. I keep a quantity of filtered water in the fridge and another volume in the cabinet with the concentrate. The water volumes are intentionally large to avoid transients, especially in the fridge, as they vary +/- 5 degrees as the compressor cycles. <br>

2. When ready to process a film I measure the temperatures of all 3 liquids and enter them into the spreadsheet.<br>

3. I adjust the volume of "warm" water in the spreadsheet until the result is 68 or a little below. The spreadsheet gives me the ratio of warm to cold water, in ounces, to achieve the correct temp for my developer tank.<br>

I use light poly beakers for mixing to avoid errors from the mass of a warm glass measure affecting the final temperature. <br>

I always err on the low temp side, and if the mixture is a hair cool I wait a couple of minutes till it comes up to spec. It is usually within a degree.<br>

The calculation is based upon the enthalpy of each fluid referenced to absolute zero (-460 F) and the relative masses. This is a calculation I use in my day job all the time to determine air volume dilutions.<br>

If there is a place here to post the excel template I'm happy to share it. </p>