Archived posting to the Leica Users Group, 2000/08/04

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Subject: Re: [Leica] Dr. Strangelens, or....
From: John Hicks <jbh@magicnet.net>
Date: Fri, 04 Aug 2000 17:08:24 -0400
References: <75.7d4e546.26bc3353@aol.com> <023e01bffe43$f7e4e3a0$140a640a@cusackknowles.com> <3.0.5.32.20000804161600.007b97d0@pop3.magicnet.net>

At 01:35 PM 8/4/00 -0700, you wrote:

>You'd get less grain but a loss of resolution to match.

  It's really not as bad as you think.
  Rodinal with fast films doesn't give very high resolution to begin with
but of course gives rather high acutance. Adding sulfite maybe takes away a
slight bit of acutance but the smallest detail rendered is still pretty
much the same. It doesn't have a tremendous effect on apparent graininess
either but just mutes it a little.
  With most modern films graininess isn't so much a problem so there's not
much to be gained and perhaps more to be lost by adding so much sulfite.
  For Delta 100 and HP5+ in Rodinal 1:50 I add 10-20g/L sodium sulfite;
this gives EI 100 for D100 compared to EI 50 without sulfite, and EI 320
for HP5+ compared to EI 200 without sulfite for identical curve shapes and
CIs. This is so little sufite that I can't seen any difference in acutance
or smallest detail rendered at 30X.
  Otoh D-76H 1:1 gives much finer grain and shows much smaller detail, of
course at a loss of acutance.


John Hicks

jbh@magicnet.net

In reply to: Message from Krechtz@aol.com (Re: [Leica] Dr. Strangelens, or....)
Message from chucko@siteconnect.com (Chuck Albertson) (Re: [Leica] Dr. Strangelens, or....)
Message from John Hicks <jbh@magicnet.net> (Re: [Leica] Dr. Strangelens, or....)