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  1. #31
    Photo Engineer's Avatar
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    A bid low in saturation and contrast, isn't it?

    PE

  2. #32
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    Left the gamma as is on the scan. It's like that for the box speed shots.

    Here is a gamma adjustment:



    The base measures 0.27, 0.72, 0.86

    The area of the clouds with the powerlines running over them measure 1.09, 1.61, 1.66
    Last edited by Athiril; 02-21-2013 at 07:48 PM. Click to view previous post history.

  3. #33
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    Very nice, but then I wonder what would happen if the gamma was increased by some means in development. Fuji has apparently done it somehow. I suggest pH.

    PE

  4. #34
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    PE; I have a suspicion this would print contrasty enough in the dark room.

    But I would actually like to increase the neg contrast by a lot while retaining mostly a straight line, for something I want to test.

    The development is very active, the higher E.I.'s have better gamma, but worse grain.

    Some shots are very grainy in deeper shadow areas, more so than normal process, but normal areas appearing to offer similar or better grain but with better detail.

    The colour is definately off, but serviceable when balanced.

    This one appears to be a higher E.I. rather than box speed, I didn't take it (and it's not me!), mixed lighting (fluro) and overcast daylight filtered through opaque plastic things in the ceiling.


  5. #35
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    Why is there color crossover in divided C-41?

    How did you process, Dan? Temps, times, etc.

  6. #36
    Athiril's Avatar
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    Oh sorry, forgot.

    The recipe I used is posted earlier, bath B pH was 11.1

    Time was 3m 15s for Bath A (just because I decided that'd be funny :P)

    And Bath B was 6 minutes.

    The temperature of the solutions at the time was measured at 23 degrees celsius.

    Initial agitation Bath A until first 30 seconds were up, then two inversions every 30 seconds.

    Bath B, same, but 2 inversions every 60 seconds.

  7. #37
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    Quote Originally Posted by Athiril View Post
    Okay I finally went to play around with another split bath out of curiousity.

    Image (quick colour balance), the sharpness and grain are pretty good for this film (made in Japan Agfa Vista 400)

    Bath A
    Pinch of Sodium Sulphite
    CD-2 – 9g/L
    Sodium Sulphite – 9.6g/L
    Sodium Bisulphite – 0.54g/L

    Measured pH 7.1

    Bath B
    Potassium Carbonate – 50g/L
    Potassium Iodide – 1.4mg/L
    Sodium Thiocyanate – 220mg/L (I’m sure my thiocyanate needs drying out too btw).

    I have to say I'm more than a little bit impressed with your results, Dan. One question: What does it mean to have a pinch of Sodium Sulphite, followed by 9.6 g/L of Sodium Sulphite? (And how much is a pinch anyway?)

    Also, I'm assuming because the PH is neutral, nothing much is happening in Bath A other than uptake of the chemistry? It is Bath B that slams it into gear?

    I guess this would have to be tried on various film formulations to determine whether it could be trustworthy, but my goodness it seems at least with this film to be delivering credible (not perfect but acceptable with adjustment) color. Would be interesting to see what would happen with something like Ektar.

  8. #38
    chuck94022's Avatar
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    Oh one more question. Was the second bath a "to completion" time, or was 6 minutes critical?

  9. #39
    Athiril's Avatar
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    Pinch of sulphite - just a very tiny amount, take it from the 9.6g/L amount that's been measured out. I just formed this habbit when mixing developers, probably from doing it with Metol.

    the CD-2 is mixed first, then the rest of the Sulphite. The Sulphite removes the HCl molecule off CD-2 iirc, and the H2SO4 off CD-4 and CD-3 (if you don't include a base initially it wont develop).

    The bisulphite drops the pH down a bit, you can go lower than I did, but 7.1 is low enough for most purposes.

    Some development has to occur in Bath A, or it is useless.

    I've tried it with CD-3 before using ECN-2 film, I omitted the Sulphite as I wanted maximum saturation/dye formation etc in Bath A. Not even 4x the equivalent amount here of colour developer agent worked. I got very thin images from +5 stops overexposed, and that was it, and they were terrible colour iirc.

    Development occurs in Bath A. Not much, but a reasonable amount. You can therefore alter affects and density with variations in time in Bath A.

    Bath B continues development, but halts to a stop when it runs out of developer.


    The last one I tried with CD-2 as at 7g/L which worked very well a well with limited testing on obscure films.


    Print Film Test #3 by athiril, on Flickr

    I was interested in it at the time to try and get good in camera pictorial results out of Vision Print Film (I've since had some luck with it using diluted E-6 first dev at 30c iirc and processing the rest as E-6), and put some 50D in as a control.

    The recipe differs to the one I used here for the Agfa film in amounts and ingredients.


    I'm currently interested in trying to figure out a good solvent style developer for C-41, ever since had some Agfa 400 go through E-6 by accident - messed up colours of course, but grain and detail were excellent.

    Quote Originally Posted by chuck94022 View Post
    Oh one more question. Was the second bath a "to completion" time, or was 6 minutes critical?

    My guess is that it's to completion by 6 minutes, as there isn't much developer sitting around anyway.


    Also one key component to 'acceptable' results is to use a good colour balance - don't use the same balance/settings you do for printing or scanning normal C-41 - that will just not work out well, as it's obviously different.

    If you're printing, shooting a greyscale on the roll and using that frame that to dial in your balance will help.

  10. #40
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    Ok, very good results!

    That said, some critical comments.

    1. CD2 is NOT good for C41 films. Image stability will be an issue.

    2. The time and temp are not too critical as this 2 bath process is self limiting. As long as you get good imbibition of chemistry there should be no problem with development except for crossover, grain and sharpness. Color would probably be ok for the most part.

    PE

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