Richard, will you describe "edge effect"? I wonder if that's what I
observed in my friends scans that I like. I wonder how and why it would do
that? Does it somehow perceive the light and dark of an image, and treat
them differently?
On Fri, Apr 17, 2015 at 2:17 PM, `Richard Knoppow <dickburk@xxxxxxxxxxxxx>
wrote:
Rodinal is an odd developer; it is rather high pH since it uses
potassium hydroxide as the accelerator. When diluted the pH is somewhat
lower or at least it does not swell the gelatin as much. There are
formulas in the literature for making "authentic" Rodinal but none has any
indication of source. Rodinal was one of the first packaged developers.
It became avaiable more than a century ago. It is a very convenient
developer but not the optimum since it tends to produce more grain and less
speed than more modern ones. When diluted it becomes a compensating
developer and at some mid-dilution will exagerate edge effects.
It is suspected that AGFA changed the formulation at least once and
maybe a couple of times during the life of the product. No one knows for
certain since it was always a proprietary formula and method of
manufacture.
Despite not being "optimum" it will develop anything and tends to be
low fog.
On 4/17/2015 10:47 AM, Dennis wrote:
On Apr 17, 2015, at 10:20, Snoopy <snoopy@xxxxxxxxxxxxxxx> wrote:
Rodinal was called the "developer for grain lovers", somewhat unjustly I
hasten to add. If you use Rodinal in weaker diltions (1:50, 1:75, 1:100)
it is a very nice developer and acts as a balancing/compensating
developer. I find the recommended dilutions of 1:10 or 1:25 as too harsh
and grainy.
Isn’t that counter to logic, in that the more dilute developers
generally give sharper and more evident grain?
I generally use the late version Rodinal at 1-50 and it is definitely
grainy.
Dennis
--
Richard Knoppowdickburk@xxxxxxxxxxxxx
WB6KBL
