tmax developer

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What is so special about Tmax developer that makes it the best suited for Tmax films? Why isn't there a formula for Tmax from scratch? Is it a kodak secret or just an innovative idea from the sales department?

-- xosni (xosni@gega.net), May 02, 2001

Answers

More the latter, IMO. I believe T-MAX developer is Kodak's answer to Ilford's Microphen, and not a very good one. Like Microphen and DD-X, it apparently utilizes Phenedione to gain about 60% more real speed without pushing. That's its claim to fame. However, in my experience, T-MAX developer is grainy and not very smooth in its gradation. That may be why there are no formulas.

-- Brian Hinther (BrianH@sd314.k12.id.us), May 02, 2001.

Kodak hasn't published one of their formulas in 40 years. They've mostly stopped selling individual photographic chemicals (you can still get a few, but they are prohibitively expensive) so they make their money by selling pre-mixed proprietary formulas. It is simply their standard business practice now.

-- Ed Buffaloe (edb@unblinkingeye.com), May 02, 2001.

Xosni: The following is from Kodak's MSDS for TMax Developer:

2. COMPOSITION/INFORMATION ON INGREDIENTS Weight % - Component - (CAS Registry No.) Concentrate: 45-50 Diethanolamine-sulfur dioxide complex (063149-47-3) 40-45 Water (007732-18-5) 1-5 Sodium bisulfite (007631-90-5) 4 Hydroquinone (000123-31-9) < 1 Pentetic acid, pentasodium salt (000140-01-2) < 1 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidinone (013047- 13-7) Working solution: 85-90 Water (007732-18-5) 10-15 Diethanolamine-sulfur dioxide complex (063149-47-3) < 1 Sodium bisulfite (007631-90-5) < 1 Hydroquinone (000123-31-9) < 1 Pentetic acid, pentasodium salt (000140-01-2)

-- Ken Burns (kenburns@twave.net), May 02, 2001.


Well, I like it for HP5+ at 1600 and sometimes TMY @1600, if I develop them together. But when the bottle is finished I will switch back to Teteanl Ultrafin Plus, at least as good as DD-X for pushing like TMZ to 6400.

-- Wolfram Kollig (kollig@ipfdd.de), May 03, 2001.

Like it or not, there's no denying that Tmax developer is able to extend the straight line region of the density/exposure curve for many films. It would be interesting to know just how and why it does this, and perhaps adapt the technique to other formulae.

-- Pete Andrews (p.l.andrews@bham.ac.uk), May 03, 2001.


Looking at the MSDS information, it appears that the activator is a self-buffered organic alkali, (Diethanolamine- SO2 compound). Anyone familiar with this substance?I wonder if the action is similar to the Hydroxylamine HCl commonly used in colour developers. The long straight line curve is certainly reminiscent of that of a colour negative.

-- Pete Andrews (p.l.andrews@bham.ac.uk), May 03, 2001.

Oh blast! I accidentally turned on bold.That should be better.

-- Pete Andrews (p.l.andrews@bham.ac.uk), May 03, 2001.

I believe the "1 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidinone" compound listed in the ingredients above is what The Film Developing Cookbook says most chemists consider the preferred form of Phenidione today. It is highly superadditive with hydroquione which accounts for an increase in film speed of between one-half and two-thirds of a stop.

-- Brian Hinther (BrianH@sd314.k12.id.us), May 03, 2001.

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