On 24/08/2020 09:58, NY wrote:
"John Rumm" wrote in message I think
Kodachrome was only ever sold with a pre-paid development
envelope in Europe, while in the states it was sold without the
cost of development. In the states there were a number of private
labs doing Kodachrome processing. In Europe Kodak did it themselves
(using a 12-stage process involving nasty chemicals and an additional
light exposure stage).

Yup I have developed my own colour reversal film (E6 process three
stages) but never tried a kodachrome. I think it had benn refined down
to six stages, but as you say, still involved a re-exposure stage.

Yes, E6 does the reversal by chemical means after first removing the
exposed silver, but Kodachrome exposes the film to a measured about of
uniform light to expose the remaining silver salts to produce the image.

Sad to think that all this has been overtaken by modern technology, and
that future generations will not have the "joys" of working in a
darkroom, fumbling around trying to get the film to catch onto the
developing spiral and to feed in cleanly, having to do that in
*complete* darkness and by feel alone. And then the sweet smell of the
developer and the acrid smell of the fixer. Making test strips to gauge
the correct exposure of a print from a negative - which varies depending
on how large you make it (move the enlarger away to get a bigger print,
so the same amount of light is spread "more thinly" across the paper). I
didn't have fancy things like a light sensor to estimate the correct
print exposure, nor even a big clockwork clock to count the seconds - I
counted the seconds by the second hand of my watch. And my darkroom was
up in the loft: there wasn't height for a table so the enlarger was on
the floor and I knelt in front of it with the dishes of chemicals beside
it. It was cold in winter and oppressively hot in summer.

I tried a couple of reversal films. One was an incredible slow Agfa B&W
film - something like 8 ASA - and the results were a bit muddy: I may
have overdeveloped after the reversal. The other was normal Ilford FP4,
developed with a reversal kit. That gave surprisingly good results.

I steered clear of processing colour (reversal or negative) because of
the much tighter tolerances on temperature which can give a colour cast
as well as just film that is too light/dark, though I did get good
results with the Ilford B&W film that was developed using C41 like
colour negs.

Yeah I kind of cheated a bit. Got a second hand Jobo CPE2 (with lift)
rotary processor. That had a temperature controlled water bath so that
you could keep the whole process on the right temp. I transferred films
to spiral and the drum in a changing bag. Processing was done on the
kitchen worktop, next to the sink in daylight :-)

Once I had the film, and then scanned it and printed digitally if I
needed prints.


--
Cheers,

John.

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