visual diff, 20min vs 60min Rodinal 1+100 ?

[jtk]

Stand processing, do you SEE a difference between (for example) 20 minutes and 60 minutes, Rodinal 1 PLUS 100 ?

In other words, in your experience does an extremely long development time (at whatever temp) produce something significantly different ( when enlarged/scanned) from a lot less time (assuming half that time is "adequate"? I'm assuming minimal agitation.

For context: I use Rodinal for sharp grain and for the unique black outline it can create with stand processing (ie without more agitation than initial inversions and a couple more halfway through). I use a Nikon scanner.

 

[jtk]

For one thing, don't assume all that changes between say 20 minutes and 60 minutes are edge effects. There is a big difference in contrast. Below are some curves for Rodinal 1:100 stand development. 30 minutes produced approximately normal contrast while 60 minutes produced significantly higher contrast. Development keeps on going.

This suggests to me if people wish to use long Rodinal stand development times to maximize exhaustion and/or edge effects, the working solution should be more dilute than 1:100.

Also note in these tests I found uniformity to be horrendous as expected.

View attachment 197458

Thanks for that intelligent response...

"edge effect" is a visual oddity..not like contrast...it's an "effect" that's easily seen if you've got it...not directly related to contrast, it's seen where two different tones come abruptly together rather than grading from one to the other. It's a localized chemical event having to do, I think (?) with a retarded line of development related to exhaustion (therefore wouldn't be visible except in stand..I wonder is possible with semi-stand).

You might be right about < 1+100. I'll try 1+200 with HP5.

I suspect Nikkor reels are the game, rather than plastique funque, for that kind of subtlety. Always loved Nikkor and Kinderman.