Re: [Leica] B&W film speed

["Dan Post" <dwpost@email.msn.com>]

Mark-
I think you have a very valid point. A lot of discussion of ISO/ASA and
developer times and temperatures has been carried on here, but You made a
good point!
Years ago the little information sheet that came in each box of Kodak film
stated clearly- that the ASA value shown was the MINIMUM value to use to get
acceptably exposed images. Clearly that was a starting point for personal
choice and not some value engraved in stone.
Processing formulas, and I still mix my own D-76, showed a range of times,
such as "7-9 minutes at 68 degrees F" rather than one absolute value.
Looking at the bottom of a bulk roll of Ilford HP5, there are times and
temperatures for various developers- unfortunately, they no longer state
that these are suggested STARTING points for development.
Each persons results will vary due to a myriad of factors. If you do your
own work, you experiment unitl you get the results you desire or need to
print, then stick with them. Someone elses times may be completely
different!
Right on!
Dan
- -----Original Message-----
From: Mark Rabiner <mrabiner@concentric.net>
To: leica-users@mejac.palo-alto.ca.us <leica-users@mejac.palo-alto.ca.us>
Date: Monday, February 22, 1999 3:09 AM
Subject: Re: [Leica] B&W film speed


>This whole thing about which film speed to set your Delta on that day
>goes right over my head. In my reading and direct experience each
>Film/developer combination has a speed which gives you adequate shadow
>detail and that's your film speed. It is not dependent on what you are
>pointing your camera at.
>You could develop that roll for a lower contrast if you are shooting
>high contrast subjects and devote a roll/body for that purpose.
>More commonly having a roll/body devoted for low contrast subjects in
>the shade or indoor or studio stuff and that roll to get an N1
>development. That way you don't have to use higher contrast papers or
>filtrations and to insure your separation in the upper tones.
>That's how I've always seen it and done it.
>Mark Rabiner