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Thread: Getting back into film - why not LF?

  1. #21

    Re: Getting back into film - why not LF?

    Thanks Philip! That’s a very good idea, I will be sure to implement it.

  2. #22

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    Re: Getting back into film - why not LF?

    Problem with "box speed" of B&W film, ISO spec imposes a set of assumptions of what the image and print making process will be. Film has an innate light sensitivity to produce a given density coupled with the development process, then on to the print making process. Where the box speed ISO spec assumption can fall flat is once an individual's print making demands are placed on the box speed. Then is when and why the box speed flat fails to meet the print making goals.

    Processed film density is a combo of innate film sensitivity to light and how much light over time the film is subjected to. Part two is development and developers. As a combo/system there is no escape from the reality they work as a system resulting in the film's latent image density and ability to be made into a print.

    Note this ISO spec film curve, note the toe at the curve beginning at 0.10. This is nil for density and not a lot if any information will be recorded at that film density. Could work for some, absolute fail for others. Beyond establishing the effective film speed that meets your specific needs, that film curve is often bent to meet the needs of a scene to be imaged and print goal needs.
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    Key is a GOOD negative that is going to closest to meeting the print goals, less becomes a patch-up, fix-up at best and software tinkering or wet darkroom tinkering is not gonna get this did.
    https://www.waybeyondmonochrome.com/...Evaluation.pdf

    Oh, films have production tolerances too like any techno item mass produced. Depending on how demanding your image making needs are, might be good to check this per film batch.

    Individuals seeking more than ISO spec for information recorded in film are likely going to alter-bend that curve to fit their image making needs. It really comes down to tailoring the entire system to your print making goals. This means working backwards with the image goals as a system from scene to be images, lens, shutter, camera, film, film post processing to print making to print mounting. Each and every facet of this system is interactive and all must be worked together in proper harmony to achieve the print goals.

    IMO, initially stay with one film and one developer. Figure one combo out first before considering any changes to film, developer and development process.


    Bernice



    Quote Originally Posted by Mikey Antonakakis View Post
    Thanks Bernice! Your point regarding "fixed-up in software" definitely rings true, and my primary aim right now is to get good negatives (to that point, I just started reading Ansel Adams The Negative). In my line of work (railcar testing engineer), I learned pretty quickly that a good analog signal is paramount - the best you can hope to do when digitizing is to not mess it up! And if you digitize a bad analog signal, well... you just end up with garbage data. There are many many telemetry sensor manufacturers that claim their software can do some magic to ensure a good signal; in fact, those sensors work great on a bench, but as soon as you put them on a freight railcar with all its vibrations, they are completely useless.

    I've already identified the first few steps for improvement in the negatives:
    • adjust ISO to a more realistic value (Foma 400 datasheet seems to have some good info, and I will look into film speed testing)
    • measure shutter speeds; already done with the Fuji 125mm, as suspected it runs at least a bit slow at most shutter speeds... it's close to perfect at 1s and 1/2, and somehow also at 1/250, the rest of the range is 10-15% slow. Oh, and 1/400 = 1/250
    • don't forget to adjust with long exposures. Foma datasheet seems to be too pessimistic here (6x multiplier with 10s shutter, my 8s exposure with zero compensation was underexposed, but I don't think by 2+ stops)
    • don't leave literal garbage in the developing tank!


    P.S. I seem to have fixed the attachments in the second photo post, hopefully they show up now.

  3. #23
    Tin Can's Avatar
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    Re: Getting back into film - why not LF?

    Wasn't there a big ISO/ASA change adapted for some films

    Like suddenly 200 speed film was now 400

    But it was the same film
    image

  4. #24

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    Re: Getting back into film - why not LF?

    Box speed is a rough starting point, depending on developer to be used, processing and all that. Box speed and brand recommended development works for some, absolute fail for others. Was touched on previously in this post.. which devolved into a non-productive word fest towards the end.
    https://www.largeformatphotography.i...ta+flash+meter

    Bernice


    Quote Originally Posted by Tin Can View Post
    Wasn't there a big ISO/ASA change adapted for some films

    Like suddenly 200 speed film was now 400

    But it was the same film

  5. #25

    Re: Getting back into film - why not LF?

    Bernice, thank you for this info - that type of "don't assume, test" approach is right up my alley! I look forward to reading the Lambrecht paper.

    As for sticking with one film - I have 46 sheets of Foma 400 left, so I'll try to get through that before thinking about using anything else. At max I will develop 4 sheets at a time, so that's at least 12 shoot/develop cycles. I'm also going to try to avoid N+1/N-1 unless I think it will be important for shots I really care about - I'll try to get as close to "N" as possible with composition, scene/timing, and exposure.

    Until I get a chance to test the film and development materials/process, I have the advice from Stearman Press at least, to meter the Foma 400 at 250 (seems like they have a good amount of experience with this film). Here's the Foma 400 datasheet, too: https://www.foma.cz/en/fomapan-400

  6. #26
    Tin Can's Avatar
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    Re: Getting back into film - why not LF?

    Thanks, I won't bother

    I use only a few different films, one developer and agitation





    Quote Originally Posted by Bernice Loui View Post
    Box speed is a rough starting point, depending on developer to be used, processing and all that. Box speed and brand recommended development works for some, absolute fail for others. Was touched on previously in this post.. which devolved into a non-productive word fest towards the end.
    https://www.largeformatphotography.i...ta+flash+meter

    Bernice
    image

  7. #27

    Re: Getting back into film - why not LF?

    Next set of 4 sheets. Fireworks shots are 10s and 20s exposures, otherwise same settings.

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    Added Flickr link to signature for higher resolution than the forum seems to allow (doesn't seem to be showing up yet, link below)
    Flickr 4x5 album

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