Push processing Tri-X 400 to 6400. Advice needed

Discussion in 'Black and White' started by greg_clements, Mar 11, 2003.

  1. I had no alternative but to expose Kodak Professional Tri-X 400 (120
    format) at ASA 6400. I am handing over the films later today for
    commercial lab push processing. I note that Kodak provides push dev
    times to 3200 but that’s where it stops. I would appreciate any
    advice on any dev times you have up your sleeve. I would ideally like
    to run a clip test but time is not on my side.

    I simply want to salvage a picture taken in less than ideal
    conditions. Grain doesn’t come into the equation as the picture will
    not be enlarged more than 2X and printed on newsprint quality paper.

    Thanks for any advice.

  2. I'd shoot another roll at 6400 and develop part of it in Diafine to see what happens. The other half I'd do using D76 with water bath development, with time in developer about 150% of normal, and three 5 minute soaks in the water at 1/3, 2/3 the way through and again at the end. NO AGITATION in the water baths! It's best to use a lift rod to transfer the reels from developer to water. While in the water the shadows keep developing but the highlights quickly exaust the developer they've soaked up. Then see what works best.
  3. Diafine isn't going to do the trick. Even at 1600, you'll have little shadow detail. At 6400 you'll have negatives that are at least 2 stops underexposed and probably too thin to print. The effective ISO of TX in Diafine is 1600, although my tests show it to be closer to 1000. There's no way to get more of a push out of it.<br>
    I'd go with Al's suggestion for D76.
  4. I second the motion to go take another roll or two at that EI, and practice on them first.
  5. The old Perfection XR-1 film developer lists Tri-X at 6400, stock dilution at 98 degrees for 8 minutes. Unfortunately the company that makes Perfection went out of business years ago but the formula for the developer showed up on one of these photo boards about a year ago. A search through the Google search engine might turn up the results.
  6. Give Acufine a try, maybe. Or take the suggestions here and increase the developing time appropriately (chart it out if you have to): http://www.digitaltruth.com/chart/tables/trix.html
    I've got one roll of Tri-X @ 6400 that I've yet to develop, and several @ 3200 that I need to develop as well. Interested to see how this works out for you.
  7. I haven't tried this yet but here's one suggestion for pushing Tri-X

    To process Tri-X at ISO 5000, you use not HC-110 Developer,
    but rather,
    HC-110 REPLENISHER. You can buy a 16-ounce container of
    the stuff at a
    good camera store, although they may need to order it from
    Kodak, so you
    may have to wait a while to get your hands on it.

    To make a solution of this special developer, make a 1:15
    solution of
    HC-110 Replenisher. That means, one ounce of the replenisher
    to 15 ounces
    of water. So, if you're processing 4 rolls of 35mm film, or 2 rolls
    of 120
    film in a one-quart tank, mix 2 ounces of replenisher with 30
    ounces of
    water. Unlike many developers that use a 68-degree
    temperature, this
    formula requires that you bring the working solution of HC-110
    to 75-degrees. The processing time is 5-3/4 minutes at
    75-degrees, with
    agitation for five seconds every thirty second.

    That's all there is to it! Expect to see grain and heavy highlight
    areas--that's part of the look.
  8. At 6400, a 400 film is receiving 16% (or about 1/6th) the light required to make a normal exposure, and no amount of "push" processing will bring up density where none exists. All you'll get in the clear areas is base fog. Meanwhile, the areas that ARE exposed will tend to block up, and grain will increase. Sometimes you'll still get a recognizable and interesting image, depending on the brightness range of the subject matter. I always used Acufine for extreme pushing, and used to shoot RE 2474 at 12,500. The film had a nominal ASA of 800 with extended red sensitivity. I got some great shots on the streets of L.A. at night during the great hippie era. I mostly used Nikons with a 55mm f/1.2 lens and no flash.
  9. Erratum: My math was wrong. at 6400, the film would receive 12.5% of the light required, or about 1/8th. Either way, it's hardly enough, but any port in a storm.
  10. ber


    Why you don't use a Ilford delta 3200 pro film ?
    Following the on-line documentation you can push it to 12500.
    And Ilford give all needed information about the processing.
    Here is the pdf file
  11. Try 1/16th of the normal light up there!

    Greg, I'll be curious to know your results- post a pic later if you can!
  12. Thank you to everyone who took the time to reply to my query. Unfortunately I did not, as I said in my query, have the time to test the films or shoot additional films to test first.The films are now in a lab ready to be collected on Friday. The lab are processing the films as if they were rated at 3200. Not ideal.I will let you know how they turn out.

    Thaks again

  13. Greg, I am sorry that this post may be too late to help. I did not see it until today. But I thought I would reply for future reference. I have checked my sources and I do not see development times for Tri-X at 6400. The exact time will depend on the developer your lab is using, but an increase of 25% for each extra stop is normal. I hope you are able to salvage the shot. I would bet that even processed at 3200, as you say your lab will do, you will have enough on the negative to make a print. After all, it is Tri-X. Good luck.

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