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  1. #21
    Ian Grant's Avatar
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    Quote Originally Posted by Photo-gear View Post
    I have foggy a bulk roll (100') of expired Plus-X Pan [2003]. After reading your post, I am wondering what could be the formula for developping this film, using PQ developer + KBr. I wish I could get an answer to it. Thx!
    There isn't really an answer, you need to use a clean working developer and do some tests, personally I wouldn't bother as the omages I make are precious to me and can't be retaken (well not identically anyway - unless a studio setup).

    Ian

  2. #22

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    PQ developers I understand are based on Phenidone
    and Mq based on metol
    Could you name a few examples of developers that are MQ PQ?

    PQ - ID11.

    What is HC-110?

    I have HC110, Rodinal and Rodinal Special. Where I live they only have a couple of Ilford ones - in the whole country...
    Which is why I need to buy ahead of time.

    So with the old cine stock, you just do it all at box speed and hope for the best?
    Well if you have a stock - itīs useful.

    I am happy to experiment and try out different versions, but for example with this 120mm - it is just one - itīs not really worth it.
    Will recompile the info I got and report back with the result.

  3. #23
    Athiril's Avatar
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    Quote Originally Posted by Rudeofus View Post
    Athiril, if you need more exposure to reach b+f+0.1 density, and require less development to get the specified contrast, then you will most definitely lose a fair bit of ISO speed.
    That's a big if, especially if you start defining the reduced contrast of fogged film as box speed, which I would not.

    If your film at a developing time of A has a dMin of 1.0, and a dMax of 1.3, and with x g/L KBr added a developing time of A has a dMin of 0.2 (where fresh film is say 0.1, so there is still some fog there) and dMax of 1.0, and at A+30% with x g/L KBr added has a dMin of 0.3 and dMax of 1.3, I wouldn't start calling it a speed loss.

  4. #24
    Rudeofus's Avatar
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    Quote Originally Posted by Auroraua View Post
    PQ developers I understand are based on Phenidone
    and Mq based on metol
    Could you name a few examples of developers that are MQ PQ?

    PQ - ID11.

    What is HC-110?
    ID-11 is the same as D-76, which is MQ. HC-110 is a PQ type developer. While the HC-110 formula is proprietary, there are published formulas for many other developers, see here for many examples.
    Trying to be the best of whatever I am, even if what I am is no good.

  5. #25
    Rudeofus's Avatar
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    Athiril, I think we just mixed up developer speed and emulsion speed. I was talking about the latter, and Bromide is unlikely to increase it. I have no opinion about developer speed.
    Trying to be the best of whatever I am, even if what I am is no good.

  6. #26

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    Quote Originally Posted by Auroraua View Post
    PQ developers I understand are based on Phenidone
    and Mq based on metol
    Could you name a few examples of developers that are MQ PQ?

    PQ - ID11.

    What is HC-110?

    I have HC110, Rodinal and Rodinal Special. Where I live they only have a couple of Ilford ones - in the whole country...
    Which is why I need to buy ahead of time.

    So with the old cine stock, you just do it all at box speed and hope for the best?
    Well if you have a stock - itīs useful.

    I am happy to experiment and try out different versions, but for example with this 120mm - it is just one - itīs not really worth it.
    Will recompile the info I got and report back with the result.
    MQ is
    M for metol
    Q for Quinol or hydroquinol
    PQ
    is P for Phenodine
    Q as above

    H110 is a trade secret but people reverse engineer the safety sheet

    these cyclic hydrocarbons can cause health problems in some people if you don't wear gloves wash off any spillage with soap and water.

  7. #27
    Athiril's Avatar
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    Quote Originally Posted by Rudeofus View Post
    Athiril, I think we just mixed up developer speed and emulsion speed. I was talking about the latter, and Bromide is unlikely to increase it. I have no opinion about developer speed.
    I didn't. The right amount of restrainer will increase useful speed of fogged film, as it'll reduce the harsh toe effect and help restore overall contrast with the right developing time.

  8. #28

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    Just thought I should post my result.
    Think it is still heavily fogged and I thin they photos are over exposed, shot it at 50 ASA.
    It was an Orwo NP20 film.
    Rodinal 12min
    20C
    Added 1 ml of a 2% potassium bromide solution. Think I should have tripled that.
    http://www.flickr.com/photos/1049799...tags/orwonp20/

  9. #29
    Bill Burk's Avatar
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    Quote Originally Posted by Rudeofus View Post
    Athiril, I think we just mixed up developer speed and emulsion speed. I was talking about the latter, and Bromide is unlikely to increase it. I have no opinion about developer speed.
    As I try to figure what the discussion is... I think more likely the idea being mixed up is emulsion speed... of the fogged film... which has already been lost.

    I've got some expired Tri-X which I rate at EI 64 because that is the exposure required to see 0.1 above Base+Fog.

    What would be the speed of that same Tri-X developed with some Potassium Bromide in my D-76 1:1?

    I'm not going to get 400 no matter what I do.

    If the Tri-X was fresh, yes, I would lose speed, it would no longer be 400.

    But it's possible that my fogged Tri-X would be fine at 64

  10. #30
    Rudeofus's Avatar
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    Quote Originally Posted by Auroraua View Post
    Added 1 ml of a 2% potassium bromide solution. Think I should have tripled that.
    1 ml of Sodium Bromide 2% contains 0.001l * 20 g/l = 0.02 g. With a 250ml batch that's less than 0.1 g/l Bromide. The first minute of film development will put more Bromide into solution than this miniscule amount. You will haver to increase that amount at least ten or twenty fold before you will see a difference.

    Quote Originally Posted by Bill Burk View Post
    What would be the speed of that same Tri-X developed with some Potassium Bromide in my D-76 1:1?

    I'm not going to get 400 no matter what I do.
    Not all hope is lost, and Bromide is not automatically evil. If you look at color developers, they contain Bromide and even Iodide, yet reach full emulsion speed. The main question is whether you have enough expired product so you can fine tune your developer.
    Trying to be the best of whatever I am, even if what I am is no good.

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