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  1. #11
    hal9000's Avatar
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    Quote Originally Posted by keffs View Post
    Looking at those curves, there is a hump in all around around density 1.6. This looks too regular, and if it was a fault due to agitation, I would have expected a more random result. If you flattened out the "bumps", then the curves look reasonable.

    One other point, the developer dilutions are not identical, so a direct comparison is perhaps not valid. I know it is probably not possible due to the amount of chemistry that can be used, but 1000ml of 1+3 will give different results to 500ml of 1+1.

    Steve
    Actually, the regularity in the bumps seems to be due to the fact that the densities go up at the wedge steps that are on the edges of the test negative, so the edges get more agitation than the central portions of the neg. Which also can be seen on prints (I have attached an example, the facade was evenly lit on a more or less cloudless day but the unevenness is obvious in the print). As far as the dilutions, I had done a number of tests at various dilutions with the CombiPlan and all curves have more or less similar bumpiness, I just chose the 1+3 as a comparison.
    Hal
    Attached Thumbnails Attached Thumbnails uneven_facade.jpg  

  2. #12

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    If your CPP-2 is brand new, it has the latest rotation motor. In that case, you should be using rotation speed "F" with Expert drums, which is around 46 rpm. The documentation telling you to use "4" is out of date and incorrect.

    Slowing from "4" to "F" might extend your gamma 0.57 time somewhat, but not from 5 minutes to 10-12 minutes in my experience. If that new time is long enough to make you comfortable with whatever "minus" times associate with it, great. If not, there's no reason not to use Xtol 1:3 as long as it's very fresh.

    My preference for developing FP4 Plus in a CPA/P-2 and Expert drum at rotation speed "F" is Perceptol 1:1. My times (here in warm southern California) for that combination, to achieve a gamma of 0.51, with a 5-minute pre-rinse, are 8 minutes 30 seconds at 75 degrees F or 5 minutes 50 seconds at 81 degrees F.

  3. #13
    hal9000's Avatar
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    Quote Originally Posted by Sal Santamaura View Post
    If your CPP-2 is brand new, it has the latest rotation motor. In that case, you should be using rotation speed "F" with Expert drums, which is around 46 rpm. The documentation telling you to use "4" is out of date and incorrect.
    Hi Sal,

    Thanks for the tip. My CPP-2 is in fact brand new, but the instruction manual that came with it suggests speed 'P' for the 1500, 2500 and 2800 series drums and '4' for 3000/Expert. The serial number of my unit is 24663. Do you have a link to a more up-to-date guide? Where did you get this info from?
    My preference for developing FP4 Plus in a CPA/P-2 and Expert drum at rotation speed "F" is Perceptol 1:1. My times (here in warm southern California) for that combination, to achieve a gamma of 0.51, with a 5-minute pre-rinse, are 8 minutes 30 seconds at 75 degrees F or 5 minutes 50 seconds at 81 degrees F.
    Thanks for this tip as well, what IE do you shoot at for FP4 with Perceptol 1:1? I have been using IE 80 for FP4 with XTOL 1:1.
    Regards from Berlin,
    Hal

  4. #14

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    Quote Originally Posted by hal9000 View Post
    ...the instruction manual...suggests speed...'4' for 3000/Expert. The serial number of my unit is 24663. Do you have a link to a more up-to-date guide?
    The late, lamented Jobo USA had a comprehensive Web site as well as a staff that kept it up to date and very informative. Fortunately, Omega-Satter, the current Jobo distributor here, rehosted that Web site. Here's the page you need:

    http://www.jobousadarkroom.com/faq/C..._Settings.html

    All the phone and email contacts at the bottom are obsolete (except "Webmaster") but the technical information is good.

    Quote Originally Posted by hal9000 View Post
    ...what IE do you shoot at for FP4 with Perceptol 1:1?...
    With exposure determined by a Zone-VI-modified Pentax digital spot meter and the negatives read by a calibrated densitometer, my FP4 Plus EI, when developed as described above, is 160. Note that I wouldn't process more than 8 4x5 sheets in 1 liter of Perceptol 1:1. Compared to Xtol 1:3, that would decrease your capability by 2 sheets per run. I'm not sure how the negatives' grain would differ from those processed in Xtol 1:3, since I've not tried that combination. Happy experimenting, Hal!

  5. #15

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    <Now I need to set my new standard developer for the JOBO developing system for my normal film (FP4+). XTOL 1:1 gave me too short times with FP4+ using rotation. I aim for a gamma of 0.57 for normal development and like to have room for at least N+2 and N-1, but I am at nearly normal development with only 5 minutes. So I will either try more dilute XTOL (1:3) or another developer. I have read that at least 25ml of XTOL stock should be used per 4x5 film, so with 10 films I would need 250ml + 750ml water which is the maximum volume rated for the 3010 drum (minimum only 210ml). Or maybe I will try another developer, anyone have suggestions for rotation processing FP4? I like to have developing times of around 10-12 minutes for normal contrast so I have plenty of room on both sides.>



    Guten tag aus Florida!

    I agree about the Jobo. A very simple method to get your film curves is to consider using the services of Fred Newman at Beyond The Zone System. Fred can easily do film tests for you, and will plot the results and send you the graphs so that you will have your own individual film speed, and the correct developing time for whatever subject brightness range your meter reading reveals. Please see the web site, or feel free to send me a private message so that I can give you additional information. Best of luck.

    Edwin Mahler

  6. #16
    hal9000's Avatar
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    Quote Originally Posted by Mahler_one View Post
    A very simple method to get your film curves is to consider using the services of Fred Newman at Beyond The Zone System. Fred can easily do film tests for you, and will plot the results and send you the graphs so that you will have your own individual film speed, and the correct developing time for whatever subject brightness range your meter reading reveals.
    Thanks, I am sure that's a great service for a lot of people but I actually LIKE to test film :o and would also feel better knowing that it is tested with my development conditions.
    Regards,
    Hal

  7. #17
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    XTOL 1:3

    I just wanted to let anyone know who might be interested - my tests with XTOL 1:3 were very good, I have good development time for normal contrast (10 min) and lots of room for expansion and contraction from N+3 to N-3. Here are my development times using 50rpm in the CPP-2 at 20°C:

    N+3 (gamma 1.000: 27 min
    N+2 (gamma 0.800): 19.5 min
    N+1 (gamma 0.667): 14 min
    N (gamma 0.571): 10 min
    N-1 (gamma 0.500): 7.5 min
    N-2 (gamma 0.444): 5.5 min
    N-3 (gamma 0.400): 3.5 min

  8. #18
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    Quote Originally Posted by hal9000 View Post
    Hi Jim, what speed do you use with your Expert drum? I have only tried JOBO's recommendation (P for roll films and 4 for expert drums).
    Thanks,
    Hal
    I turn on the power switch until it clicks on, and no further. This is the slowest possible rotation. I began doing this when I awitched to pyrocat hd and have never had streaks.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

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