RE: filmscanners: Scratched Negs & Home C-41 processing

[Tim Victor <TimVictor@csi.com>]

On Friday, January 26, Tony Sleep wrote:
> On Fri, 26 Jan 2001 02:56:54 -0500  Tim Victor (TimVictor@csi.com) wrote:
>
>>  They agreed with what
>> Michael Wilkinson just said, that film manufacturers don't
>> take presoaking into account and it has noticeable effects
>> on development which are different for different types of
>> film stocks.
>> 
>> I'm concerned that with such a short development time, it
>> will be difficult to keep the temperature of the actual film
>> reasonably near the specification without a presoak,  but
>> that the presoak, by pre-swelling the emulsion, might alter
>> the result anyway.
>
> You are doing the right thing by pre-warming the tank in the water bath. 
> Although pre-soaking takes care of temperature concerns nicely, the emulsion 
> being swollen with water affects the rate at which developer is absorbed.

Thanks for the comments, Tony. It sounds like we're all in agreement
on this.

Btw, due to some clumsy editing on my part, the second of the paragraphs
that you quote was actually from Alan Tyson. In my sleep-deprived
condition at the end of last week, I accidentally included it in my
reply. But having it in there didn't change my meaning at all, oddly
enough.

> At worst, the 
> diffusion rate through the layers will be slowed so some layers receive less 
>or 
> more development, leading to possible casts or crossed-curve effects.

Any thoughts on how much that really matters for negatives that will
only be used for scanning? Whenever crossed curves are mentioned,
it usually seems to meant to imply that the life on earth as we know
it is ending, as far as that image is concerned. But if I'm routinely
setting the white and black points independently for each channel as
part of my post-scan routine, would it still be such a show-stopper?

I'll grant that it's better to stay as close to by-the-book as possible,
but for all I know my curves might be crossing already. I'm not certain
that I'd be able to tell if they were.

Best wishes,

Tim Victor
TimVictor@csi.com