I know this subject has been discussed about a million times before, but I'd like to get to the root of it.
Has anyone ever run actual tests to verify that twiddle stick agitation causes uneven development or is inferior to the inversion method? I've read a fairly large number of threads discussing this issue and virtually all the responses seem to be absolutely sure that the spinner is inferior and causes problems; I suspect that the statements are simply parroting what that individual has heard or read elsewhere, not the results of a formal analysis. Statements vary from end to end density differences and/or edge to edge density differences or generally an overall poorer method of agitation. To me, spinning is Jobo rotation in the horizontal axis without the film exiting the developer into air space.
What I'm getting at here is the proposition that spinner agitation causes uneven development seems more likely to be 'photo mythology' that has been propagated over the years and has taken on the aura of being 'gospel truth,' it appears to not be the result of a formal in depth side by side test.
What I'd like to ask is do any of you know of a formal experiment that has been performed to determine if there really are dramatic differences between spinner and inversion methods of agitation. And I'm also asking if such an experiment has been conducted, has it been performed to the level and extent of the in depth experiments performed by the late Richard J. Henry in his last book 'Photographic Controls...?'
If anyone knows of direct evidence of such experiments, could you please provide links to the information? No hearsay, please. I'm asking because I am sick and tired of reading that it is indeed fact without any factual evidence or proof to back the assertion.
PS I am completely aware of the Ilford recommendation only using the spinner for the initial cycle of agitation but provides no additional information why you shouldn't continue with the spinner for the duration of the development cycle.
Perhaps Mr. Benskin knows of the real truth; it's sad that PE is no longer with us to proffer advice. He is missed! Matt King, do you know of actual evidence of any differences?
Has anyone ever run actual tests to verify that twiddle stick agitation causes uneven development or is inferior to the inversion method? I've read a fairly large number of threads discussing this issue and virtually all the responses seem to be absolutely sure that the spinner is inferior and causes problems; I suspect that the statements are simply parroting what that individual has heard or read elsewhere, not the results of a formal analysis. Statements vary from end to end density differences and/or edge to edge density differences or generally an overall poorer method of agitation. To me, spinning is Jobo rotation in the horizontal axis without the film exiting the developer into air space.
What I'm getting at here is the proposition that spinner agitation causes uneven development seems more likely to be 'photo mythology' that has been propagated over the years and has taken on the aura of being 'gospel truth,' it appears to not be the result of a formal in depth side by side test.
What I'd like to ask is do any of you know of a formal experiment that has been performed to determine if there really are dramatic differences between spinner and inversion methods of agitation. And I'm also asking if such an experiment has been conducted, has it been performed to the level and extent of the in depth experiments performed by the late Richard J. Henry in his last book 'Photographic Controls...?'
If anyone knows of direct evidence of such experiments, could you please provide links to the information? No hearsay, please. I'm asking because I am sick and tired of reading that it is indeed fact without any factual evidence or proof to back the assertion.
PS I am completely aware of the Ilford recommendation only using the spinner for the initial cycle of agitation but provides no additional information why you shouldn't continue with the spinner for the duration of the development cycle.
Perhaps Mr. Benskin knows of the real truth; it's sad that PE is no longer with us to proffer advice. He is missed! Matt King, do you know of actual evidence of any differences?
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