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  1. #11

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    Quote Originally Posted by Alan Johnson View Post
    Rudeofus,
    My comment was not directed at you.
    I'm just saying to Michael don't write off high resolution scanning as useless simply because nobody has evaluated its ability to distinguish different developers yet.
    It could be done on DPUG using say Perceptol, Xtol and Rodinal.
    It's probably not as good as the enlarging method but potentially useful if anyone makes a homebrew to test.
    It has not been evaluated yet.
    That wasn't my primary issue with the test. It was that the comparison was between films developed in completely different ways, not just in different developers. If you want to evaluate the relative graininess of two developers you need to reduce the effects of all the controlable variables which can influence graininess, as much as possible. That means not only using the same test subject, but perhaps most importantly, exposing at a common EI and contrast index. If you don't do that, you have no idea which developer is grainier. In the case posted above, we have exactly this situation. The two films we exposed and processed in substantially different ways. Pushing film is overdeveloping, in this case, a lot, which increases graininess significantly and reduces sharpness. Pushing also means developing to higher contrast, which makes it even more difficult to compare graininess. So even if you had perfect, high resolution scanning, you cannot draw valid conclusions from this test. I'm not saying you need to lock yourself in a lab for a year doing tests, but at least start by rating the films at the same EI.

    By the way, I have no bias when it comes to these home brew formulas. I'm not trying to bash Mark's developer, or that Ryuji guy, or anyone else. On the contrary, not testing things properly is selling yourself short.
    Last edited by Michael R 1974; 01-21-2012 at 08:46 PM. Click to view previous post history.

  2. #12
    Rudeofus's Avatar
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    Michael,

    I wholeheartedly agree that the comparison of results as posted by me was not overly scientific and I think I clearly expressed this in a few postings here in this thread. I am fully aware that grain gets larger as one pushes film and comparing results from different subject matter opens a whole new can of worms. This was my first experiment of hopefully many to come and future comparisons will also include more suitable groups of images.

    Browsing the threads about home brewing and experimenting I see lots and lots of folks doing incredible stuff, posting recipes&results, but all these threads were from 2005 or 2007 and have since died down. A common response to "here is my recipe with results" used to be "Look, I tried to improve it here" and "I changed this and that and here's what I got". In 2012 the usual response is "and now you should" and "I have stuff which is better than yours but I won't tell you".

    I gave reasons why I still posted my results: dispel the myth that home brewing requires an expensive scientific library including Japanese language books, big laboratories with expensive equipment and months of experimenting with dozens of wasted film rolls before the first roll finally reveals discernible images.

    Here is what it took me:

    1 scale which can resolve milligrams: 100 €
    chems&containers (which will last me for years of experiments): 250 €
    time spent learning stuff in various threads: 2-3 low intensity weeks
    time spent measuring, dissolving and mixing chems: 2-3 hours
    Trying to be the best of whatever I am, even if what I am is no good.

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