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  1. #11

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    I used a method from this Web page (part 2 is on another page) to calibrate Fomapan 400 to Gainer's PC-Glycol developer. I'm not an expert on this topic, so I can't claim with authority that this method is really the ideal way to do the job, but it seemed helpful to me. The drawback is you're likely to need to shoot at least two 36-exposure rolls of film for each film/developer combination, and futz around in the darkroom making test prints from them, as well.

  2. #12
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    OK.....
    Im going to throw my 2cents in here just to hear - a) Im crazy, or b) Im a genious, and c) Crazy genious with a few flaws in the system {and hope you explain those to me so I can learn sumthin}

    I set up a regular piece of paper on a wall, evenly illuminated by two lights @ approx. 45deg to the surface (I set up each light individually, using incidental metering to get some even f/# combo -usu. f/5.6 @ 1/2 sec)

    When both lights are on, the exposure, incident metered, is idealy f/8, 1/2 sec @ factory ISO.

    I then switch to a 1deg spot meter.

    What's on the paper - regular inkjet print on regular paper, a target containing a WIDE range of tones... I found this weird graph on the internet that shows the relative strengths of field forces in gray scale... nevermind that... basicaly you want something that has at least ten steps ranging from dead black, to paper base white, and steps in between... (when I get home Ill try to upload my target image to this thread)

    The target is basicaly a print out of a step wedge, the more steps, the better, I believe the tar

    I then read off the target with the 1deg spot meter the proper exposure for the lowest value, middle value, and highest value. Now I have the zone V exposure info for all the values on the page in front of the camera.

    I set up the cam perpendicular to the plane of the paper, and take a shot at 3EV below the zone V reading for the darkest band, then one shot at the zone V reading for the middle band, and one shot 3EV over the reading for the pure paper base white band...

    Waltz over to the dark room, and process to what I consider "normal" for the dev/film combo. If I have no Idea what that should be, I just start with six minutes, and keep going up till I like the results on the negs. In the ideal dev. time, I should not loose the darkest band at the low end of the scale for my first shot, have a full spread for the second, and not loose the lstep between the lightest two bands at the high end for the third shot...

    Repeat above ad nauseum.

    Those negs which appear to have a distinct band for each of the bands on the target get taken into the dark room and printed, or taken to the scanner, and measured with the flatbed's "densitometer" . .. there, Im looking to be able to measure a diff. between all the bands... as well as register base + fog... and the .15 step up to zone I.

    One of the nice things about shooting the equivalent of a step wedge onto film is that I KNOW what the exposure steps are between my bands... so if I start to loose bands on either the high end of the tones or low end of the tones, I know Im either pushing or pulling the film (and approx how much in EV) . . . for it's given ISO. When I have all the bands, I consider that I've reached "normal" development.

    I havent taken the steps all the way thru with the print speed testing. . . i.e. I understand that I should use a step wedge and get my "normal" print times for paper/dev combos, THEN print my "normal" negs to the "normal" time on paper...

    Still, having confidence that Im getting a normal neg encourages me to feel that Im walking into the dark room with what I need to start with for the best possible prints... no use trying to get beautiful tones with a blocked/underexposed neg.

  3. #13

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    Why not just use a Stouffer step tablet?

    What type of light is your source? If it is tungsten, it will render somewhat different on film then daylight. If your lights are not at 45 degrees to the axis of the lens you have the potential of flare affecting your exposures.

    Ideally you would want to tailor your negative to the paper...the paper contrast within a grade is not amendable to the same extent as the camera negative. Thus many establish the paper characteristics before they work on the negative film speed and development.

    There may be other considerations. These, that I have mentioned, are readily apparent from what you have described.

  4. #14

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    No offense guys, but you're complicating things way more than necessary. The most efficient, most effective, most revealing, most informative way of getting your dev/times/dilutions/temps etc... is by using BTZS. It's really very, very, easy! It tells all! There's NO guesswork! When you get in your car in the morning you enter through the driver's door (if you're driving of course). You don't get in the passenger side then climb over the seat into the back, out the back door and then into the driver's side. By that time you've forgotten where you were going. Seriously, make it simple... call Fred at the View Camera Store and get the details. BTZS is the best kept secret in photography. I am not affiliated with any of the above, just a lover of the system. If you want to hurry up and get your testing over with so you can get out and do some shooting... get BTZS. Phil Davis has done all the hard work for you!

    TRY IT!

  5. #15
    Pastiche's Avatar
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    Im assuming Mr. Miller is reffering to me...

    Well... I plan on using a Stoufer step wedge. Just havent bought one yet...
    But it's the same idea. And yes, the lights are at 45's . . and.. ..
    I mostly shoot in studio... with daylight balanced bulbs... Im sure it's not the exact same thing...
    I can dig working from the paper backwards...
    I've been dong all the enlarging at the school's lab... and graded paper was not the going thing...
    I'm planning on moving into graded paper after I feel I've gotten a very thorough handle on VC and split filtering (from a color head) . ..
    I definetly concede that the graded paper will give me better tones... overall, but I just dont want to gloss over a standard practice...
    And thanks on the regards about the process... it's always good to have another photog to think with.

    To Sandstorm-
    the thing is, Im still experimenting with new developers... and films... and dont see any end in sight. .
    Plus, taking the work to any third party is like taking the car to the mechanic to get the gas tank topped off... It's just something I'd rather know that I can do routinely, well, and precicely myself...

    Actually, learning to speed rate my film taught me more about exposure control than I ever had a clue existed... not by reading about it in The Negative, but by seeing it in my work first hand.

  6. #16
    abeku's Avatar
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    Hi Jimi,
    I've been using the method described by Chris Johnson. The first 120 roll is used to establish the EI by exposing for the shadows and get details in zone III. Then you need to analyse the results by making prints (on the paper you're going to use in the darkroom). On the final print you analyse how under/overexposed the Zone VIII is and adjust the developing time on the second roll of film you're shooting. I usually cut the 120-film in two pieces, in order to save some money. In the link attached above, there's also a chart for HP5 and FP4 in various developers, in my hands those times are very much the same what I'm using.
    Good luck!

  7. #17

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    huber

    you don't have to drop your work off anywhere, you can do it yourself with the plotter software. that's what I do. Although, you do have the option to have Fred do it for you. Today I tested (for Jobo processing) tmax100, 400, txp320, fp4, hp5, and efke 100 developed in clayton f76. I now know in intimate detail everything I need to know to control the density range of these films to fit my favorite paper. All in 5 hours work. That includes film speeds, contrast indexes for n-1 thru n+2. If you are indeed experimenting, this system will save you countless hours. You'll thank Phil Davis once you see it's value.

    best
    Sandstrom

  8. #18
    Pastiche's Avatar
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    OK. . now youve got my interest. . .. Ill check it out.. Thanks.

  9. #19

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    Great... that's what this place is all about... photographers helping other photographers. Glad I could give back a little as I've received a lot from others here.

    Once you're on to the system, spread the word to others so they can reap the benefits as well. Phil Davis has done a great service for us. Thanks Phil!

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