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  1. #11

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    Jay & Gadget Gainer - Many thanks for your answers. I didn't realise that development time didn't make any difference to the detail in the negative (as long as it's correctly developed). I'm having one of my blonde weekends

  2. #12
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    Why use "short" times - less than 5 minutes?

    Different dilutions of a given developer will, in my experience, have a different effect on the film.
    A certain film in a certain developer at a given strength will "look" different (bear with me gang - I'm trying to keep it simple) than it would with the same developer at another strength. We may find an "improvement" - depending on what we are trying to do - with "R" developer at 1:50, 10 minutes - instead of 1:100 for 30 minutes (this whole thing depends on aesthetics ...), and a still greater improvement at 1:15 for 7. Extrapolating, the times for a still greater concentration could well decrease to something under 5 minutes with "X" dilution - and the idea of following the "Not less than 5 minutes" rule would limit that course of action.

    Developing time itself is of little concern to me - the characteristics of the negative ARE.
    Carpe erratum!!

    Ed Sukach, FFP.

  3. #13

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    Quote Originally Posted by Dr.Kollig
    In 2002 I received a developing agent similar to Ascorbic Acid, he named it SEB, it is used for developing microfilms. Developing microfilms is something like 30 secs, his developer is high in Phenidone and SEB plus Carbonate.
    So I formulated my own film developer (named K2), using borax as alkaline and ended up around 2 mins, using a Jobo CPE, no problems, fine grain but poor sharpness. The second version (K4) used borax/boric acid like ID-68 and gave times of 4-5 mins, similar grain size and still sharpness too low.
    A high concentration of Phenidone gives high initial speed in developing, for normal film the minimum seems to be around 60-90 secs, even 2 g Phenidone could not get below these values with reasonable contrast. I read some eastgerman book that Aminfunctionality gets to the silver quicker than Hydroxyfunctionality, so based on that Phenidone attacks first and the time for this reaction might around 30-60 secs, than the Phenidone gets recovered by HQ and/or Ascorbic Acid. If the later reaction is slower, it would explain the low contrast below 60-90 secs, basically a Phenidone-only developer like XR-1 is pretty low in contrast, HQ etc. is required to build up contrast.

    So anything longer than 90 secs sounds reasonable to me, just let me know if sharpness is good, as I gave up on that K2/K4 developers and switched to a staining developer based on Catechol combined with potassium hydroxide diluted 1:1:90 developing times around 20 mins and great sharpness with 100 speed films but grainy with 400 speed films.

    Regards,

    Wolfram
    Hi Wolfram,
    Perfection XR-1 contains Phenidone, Metol and Hydroquinone.

    I suspect (from its development behavior) that XR-1 may also contain some form of Ascorbic Acid. If I get sufficiently curious about this I may perform mass spectroscopy on one of the remaining original packets of XR-1 in my collection.
    Tom Hoskinson
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  4. #14

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    I have no idea about Jay's developer but many high energy developers that develop film in less than five minutes do not give full emulsion speed compared to a standard like D76. Also, many people believe, and I have seen a lot of evidence of it myself, that very dilute developers and minimal agitation give not only greater emulsion speed but also more apparent sharpness.

    Sandy

  5. #15

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    Quote Originally Posted by jdef
    Wolfram, this developer is extremely sharp. Thanks for sharing your experiences with fast acting developers.
    Jay
    Fine, 90 secs should do for a japanese green tea. I will give it a try one I've found the time to expose some film in DAYlight.

    Let's see if the used developer can be used to sharpen the razor blades, so fixing timne could be used for shaving.

    Regarding film speed, there is a minimum of, I think, 4 Ag atoms to start development, some developers require 6 Ag in a crystal, so high energy developer which can do 4 Ag crystals should yield full speed. Please do not quote me on the Ag numbers, it is rather the idea that higher energy developer can developer smaller numbers and giving higher speeds.

    The idea of diluted developers is gaining speed film in relation to contrast, low density areas are developing all the time, as they need very low numbers of developer molecules, while high densities are controlled by exhausting.

    So the idea would be a high energy developer being able to develop all crystals and control density by a very short developing time.

    Regards,

    Wolfram
    Colour? We can always use an airbrush later...

  6. #16

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    Quote Originally Posted by Tom Hoskinson
    Hi Wolfram,
    Perfection XR-1 contains Phenidone, Metol and Hydroquinone.

    I suspect (from its development behavior) that XR-1 may also contain some form of Ascorbic Acid. If I get sufficiently curious about this I may perform mass spectroscopy on one of the remaining original packets of XR-1 in my collection.
    You're correct Tom, just the rate Phenidone:HQ 7:1 instead of 1:10, is the big difference. I use the patent formula A with Efke 25 and 50 and expose the films at 100/200 ASA, 15 mins at 20°C. Zone 1 might not be at 0.1 but overall the negatives are looking good. You can not get negatives with less grain at 200 ASA than that combo - in 35 mm. But higher sharpness, as I think Efke 50 is not that sharp.

    Wolfram
    Colour? We can always use an airbrush later...

  7. #17

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    Gentlemen/Ladies: Let's start the engine...

    Maybe we should do a 2005 APUG competition on the fastest useable b/w developer?

    I guess, Morton is already running experiments on straight Rodinal pumped thru the film canister.

    Good night, I'll have to start dreaming about it.

    Wolfram
    Colour? We can always use an airbrush later...

  8. #18

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    Quote Originally Posted by jdef
    My problem with dilute developers, is the compensating effect, which accounts for the increased film speed, and reduced contrast. A good solution for high contrast scenes, but not advantageous in my portrait work.

    Jay
    The idea that very dilute developers are only capable of reduced contrast is a widely held misconception that can easily be disproved with a few simple tests.

    For example, few would argue with the fact that Pyrocat-HD at the 1:1:200 dilution is a very dilute developer. At that dilution one liter of working solution contains only 0.25g of pyrocatechin and 0.01g of phenidone, a remarkably small amount of reducing agent. Yet this highly dilute solution will develop all films to their maximum possible CI, using minimal or semi-stand agitation, in 45 - 90 minutes. And as a bonus you get what is for all practical purposes a real increase in EFS of up to 1/2 of a stop, and great apparent sharpness. In fact, one person who uses this method of development commented to me that it makes his negatives developed by other procedures look out of focus.

    Sandy

  9. #19

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    Apologies if someone already made this comment and I missed it, but I find the biggest issue with short development times is control of contrast index. If you're normal development time is, for example, two minutes then the difference between N and N-1 is probably going to be on the order of 15 seconds - not a lot of margin for error. Granted, it's not the end of the world if you're off by 15 seconds and have to change paper grades or print with a different contrast filter than usual, but it is a consideration. I prefer my normal development times in the 8-10 minute range because it gives me more margin for error.

    Chris

  10. #20

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    Quote Originally Posted by jdef
    Sandy,
    I've read where you've written that you haven't seen adjacency effects with fast films, and recommend slower films for those techniques.
    Jay
    Gee, did I write that? If so I must have had a temporary loss of memory because I have developed virtually all of my HP5+ roll film with minimal agitation for years and years precisely because of enhanced adjacency effects. It is true that the adjacency effects are often much more pronounced with medium and slow films, but with appropriate dilutions and agitation I believe you can get enhanced adjacency effects with any film.

    Sandy

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