[Leica] Neopan-Xtol Xpert-Tease Sought

[freakscene at weirdness.com (Marty Deveney)]

Bob,

Xtol works so well because ascorbates are efficient developers of silver at 
moderate pH, even at low concentrations.  This is why Xtol still works well 
at high dilution.

Thin or not the scan I could see looks great.  If you plan to scan and print 
digitally and you like the way this looks, how dense the negs are (or not) 
doesn't matter.  If you want to print in a wet darkroom, try it and see if 
you can get prints you are happy with.  Again, if it works, there's nothing 
to fix.

I have done a lot of testing with Xtol 1+3 and the Neopans.  I use EI640 and 
13.5 min @ 20C for Xtol 1+3.  This gave very low base fog (I particularly 
like the very clear base and low base fog of Acros) and a (measured with a 
calibrated densitometer) CI of 0.56.  Higher speeds and/or longer times 
didn't effectively increase the speed for me - the CI increased 
disproportionately to the densities in the shadow values.
  
I have also done a lot of wet printing and measurement of print and negative 
densities.  I could never get sufficient shadow contrast for my taste in 
silver prints from negs with a FB + fog of 0.1.  Essentially, this means 
that the ISO speeds are good for standardisation, but adjust for your own 
taste.  Sophisticated testing is not necessary if you develop using 
consistent methodology, keep records and know what you like.

We can argue about this until we're blue in the face, but if you're happy 
with the end product, it doesn't matter.

As an aside, LuGer John Black developed (pun unintended) an extremely novel 
film developer using ascorbates and phenidone in a tris buffer that is 
stable in long-term storage.  It is still susceptible to contamination in 
the dilution water, but using deionised water improves the consistency of 
results when using D76 and other traditional developers too.

Later,

Marty






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