Question about Neopan Acros 100

[Lee L]

Is that polynomial interpolation Lee?

It's a logarithmic curve. It seems to do a good job with almost any typical film development for gamma vs. developing time. I've used it with data having 5 or more observations and it holds well.

y=a*ln(x)+b

in this case
a = 14.5205569019166
b = 16.2429697851392

x = gamma
y = development time in minutes

I use http://scidavis.sourceforge.net/download.html for this (and investigating reciprocity). A spreadsheet should do as well. Just plug in the data, chart it, then click on the curve in the chart and add a trend line, and have it display the formula.

I have gotten grief for showing the math before on APUG, so didn't post it in the original. Some people like black box solutions. And I won't respond to comments on significant digits in the variables above either, it's cut and paste from a computer program.

Lee

 

[Anon Ymous]

Interesting, thanks!

 

[Keith Tapscott.]

I have started working with this film and am ready to develop some rolls.

Here is my question: Which of these would be the best developer?

• Kodak D-76
• Kodak Microdol-X
• Ilford ID-11
• Ilford Perceptol

Any of you have an experience with this?

Tommy

D-76 and ID-11 are near enough identical and Perceptol is similar to Microdol-X which Kodak has recently discontinued.
I would use D-76/ID-11 or try Paterson FX-39.

 

[Rick Jones]

IMHO exposing the film properly, determining how to achieve the best C.I. for your purposes and your decision as to whether or not to use a tripod are way more important than which developer to use. Sooo just pick one and learn to use it well. If there was a best developer my guess is EVERYONE would be using it. IMHO