Polydol, D-19, DK-50, and other things.

Discussion in 'Black and White' started by robert_macdonald, May 8, 2004.

  1. !st pic was shot on 400 T-max 35mm in DK-50 1:1, following times for Kodak T-max RS Developer. The image below is on expired Panatomic-X, March of 1976, Processed in DK-50 1:1 for 6 minutes at 68*F.

  2. I only recently saw the recommended capacity limits for D-76, and yes at those it is a waste of money.

    HC-110 isn't so cheap, but at the recommended capacity you get over 100 rolls from a 1L bottle of concentrate.
    elliot_myrick|1 likes this.
  3. - In what way is a mixture of Metol, Hydroquinone, Sodium Metaborate, Sodium Sulphite and Potassium Bromide 'natural'?

    Look. DK-50 is no longer available, and hasn't been manufactured for some considerable time. So why keep banging on about it?

    If you want economy, I can post a formula for a Rodinal substitute that you can make out of Paracetamol (Acetaminophen) headache tablets, caustic soda and potassium metabisulphite. It probably costs around 5 UK pence - 7 US cents - per film.
  4. elliot_myrick|1 likes this.
  5. Here it is as text

    From the Kodak's "Processing Chemicals & Formulas for Black-and-White Photography", J-1 Professional Data Book, 1977:

    Kodak DK-50
    Warm Water ( ~50ºC ) CAS # 7732-18-5 500 ml

    add and dissolve
    Kodak Elon, P-Methylaminophenol Sulfa CAS # 55-55-0 2.5 gram
    Sodium Sulfite ( Anhydrous ) CAS # 7757-83-7 30.0 grams
    Hydroquinone CAS # 123-31-9 2.5 grams
    Sodium Metaborate CAS # 16800-11-6 10.0 grams
    Potassium Bromide ( Anhydrous ) CAS # 7758-02-3 0.5 grams

    then add
    Cold Water ( ~20ºC ) CAS # 7732-18-5 to make 1,000 ml

    Clean-working and moderately fast, Kodak DK-50 Developer is extremely popular with commercial and portrait photographers. It can be used with or without dilution, in a tank or tray, to produce crisp-looking negatives from all types of subjects. DK-50 Developer is highly recommended for portraiture.

    Development Recommendations: For tank development of portrait negatives, dilute with an equal volume of water; develop about 10 minutes at 20ºC. For tray development, use without dilution; develop about 6 minutes at 20ºC. For commercial work, use without dilution. Develop about 6 minutes in a tank or 4.5 minutes in a tray at 20ºC.
    elliot_myrick|1 likes this.
  6. eBay still has plenty of people selling DK-50. Also, Photographers Formulary sells the developer. Otherwise, you can mix the developer from raw chemicals yourself. So, what is the problem? The DK-50 developer is more economical than D-76, which uses 100 grams of sodium sulfite per liter and uses triple the amount of Metol and Hydroquinone than DK-50.

    With that being said, D-76 is a total waste of money, aside from lower processing capacity and the excessive amounts of sodium sulfite and the two developing agents, aside from being able to process more films with DK-50 than D-76 and with excellent tonality separation and fine grain. Rodinal sucks, aside from being highly toxic as it uses caustic soda (AKA Lye) which causes burns, coarser grain and having to crush up Acetominophen, etc and its preparations. DK-50 is a much better choice! I call DK-50 the T-Max powder developer and for a good reason!

    Dilute your DK-50 1:1 and you're good to go and it's replinishable, if you so choose to! Just dilute your replinisher 1:1 as well!

    SO YES, It's worth it to "keep banging on about it"! Besides, follow the development times for T-Max developer 1:4 and you can't go wrong, unless it's specified as with Kodak 400TX films.
    Last edited: Nov 19, 2018
  7. I still prefer DK-50 for processing Kodak sheet film. But 35mm Plus-X and Eastman 5222 have great tones with it too. I have one gallon package left to use and then I will start mixing my own for when I need it. Currently don't have any mixed since I don't have and sheet film to process at the moment. For 35mm and 120 I use HC110 dilution H which isn't too expensive.
    elliot_myrick|1 likes this.
  8. Both Xtol and T-Max developers are recommended for the highest EI of TMZ and Delta 3200.

    Neither one has a time for DK-50 on its data sheet.
  9. I use DK-50 1:1 and follow the processing times and temperatures for Kodak T-Max film developer for ALL films. I never had any issues. You may want to give it a try. You won't be disappointed!

    Of course Kodak won't recommend times for a product that works so outstanding, aside from Kodak DK-50 being discontinued back in 2012. I still am able to still find DK-50 on eBay. Photographers Formulary still makes it. DK-50 is also a published formula.

    If your "Data Sheets" have times for Kodak T-Max, you have those times for DK-50 1:1. Use them.
    Last edited: Dec 9, 2018
  10. This is amazing, an almost new thread about DK-50! In 2015 for reasons I don't remember, I decided to make and try DK-50 on Plus-X 1:1. I was beyond blown away! What grain there was, minimal and tight. Nothing like one would expect in theory. Great tonality. Where have you been for the last 65 years?

    At the time I was very much involved with APUG, which I see has rebranded itself. I did some posts there which you may find of interest. Anyway, about then I had to move and here it is 2019, ready to get back to film and developing. So I've been going through all my records and notes and internet searching as I get ready to go down the rabbit hole again.

    Elliot, you observations about being equal to T-Max times will be a life saver. Development times has been the bottleneck for DK-50, for sure. I have printed out the pages from the Massive Development Chart filtered for DK-50, and all films for T-Max developers. BTW, that motorcycle image is stunning, right on what I got with my short lived experiments.

    I also started experimenting with DK-50 in a divided format; god, I've been a slave to the idea of divided development for 40 years.

    My original post on APUG: DK-50, Still alive and well?
    elliot_myrick|1 likes this.

  11. It's now May of 2020 and I'm still loving it! I'm now also hooked on DK-60A 1:If you also have some DK-60A, dilute it 1:3 and follow the times for D-76 Stock. You can reuse this developer in its diluted form and can process up to 8 rolls per quart without replenishment. If you have the DK-60aTR, you dilute the replenisher 1:3 and replenish the developer 1:3 with it. I still have a bunch of cans of this stuff and try to stock up on both of these developers the first chance I get.

    DK-50 and DK-60A are awesome developers and the formulas are nearly identical, with DK-60A having more balanced alkali and Sodium Sulfite than the DK-50 and has finer grain, too!
    Last edited: May 14, 2020
  12. It struck me when I looked at FX-37 (which a lot of people love) that it is DK-50 with one tenth the weight of metol substituted by phenidone. I use the FX-37 times and dilute further with longer times, of course. One shot.
  13. Yes, the FX formulas are excellent. I used DK-50 way back when it was common, but it's an old developer designed for the films of the times. If I ever process again, I'll probably stick with my FX-37 and FX-2, assuming glycin is available. FWIW, I made up my own concoction with PPD and ascorbic acid (or ascorbate, can't remember) that was fairly successful. It managed to combine very fine grain and good edge qualities.
  14. Ascorbic acid can't be used as a developer Conrad, its pH is too low. It has to be converted to an ascorbate salt by the addition of a base, but adding the developer's activator alkali will do this automatically.

    Commercially sold Vitamin C powder nearly always comes in Ascorbic acid form, and will need the addition of extra alkali in a developer formula to convert it to an ascorbate salt.

    IIRC, it takes the equivalent of 2.2 gm of sodium hydroxide to 10gm of ascorbic acid to complete the conversion to sodium ascorbate.

    As far as I can tell, almost any old Metol-Hydroquinone formula can be turned into a Phenidone-Ascorbate version to advantage (less toxic, less costly, and easier to obtain. With possibly better keeping properties). The most active combination seems to have a ratio of around 40:1 in weight between the Ascorbate salt and Phenidone. Keeping the Ascorbate at roughly the same weight as the Hydroquinone in any MQ formula seems to work.

    However, I'm not sure if there's any superadditivity between PPD and Ascorbate, so the Ascorbate probably just acts as an anti-oxidant or regenerant, similar to sulphite.
    Last edited: May 31, 2020
  15. Murray- great link. I must have missed that one. Joe, see, your knowledge is better than my memory. It's been a long time but I was very pleased with the fine grain and little trade-off of anything else. People seem scared of PPD but the usual lab hygiene is fine. Heck, the stuff is/was used in hair dye.
    murray_kelly likes this.
  16. It is an interesting thread. There is alot of off theme comments and I was the guilty one that side tracked it to Imagelink. ;)
    I finally got the chemicals but forgot about doing anything with them in the end.
  17. Still is.
    In fact the thought's crossed my mind a few times to see if a film could be developed in hair dye.

    I suspect that these days it's easier to buy CD3, or one of the other PPD derivatives used for colour developing if you want to experiment with a super fine-grain developer.... or just use XP2 Super.
  18. I didn’t realize until now that Ron Mowrey passed away this last February.
    murray_kelly likes this.

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