Sure. When film sits in developer for a long time without agitation, it is first and quickly exhausted in the image highlights - the
darkest part of the negative. However, the shadows -
the lightest part of the negative - continue to develop. The middle tones are somewhere in the middle - they continue to develop, though not as completely as the shadows.
This has three effects:
1.
It compensates the highlights, thereby keeping them from blocking
2.
It fully develops the shadows, thereby giving you full box speed ASA (which normal development essentially never does).
3.
It expands the middle tones, thereby giving middle grays a lot of tonal richness.
As an aside, with semistand, we very briefly agitate once in the midpoint time to reduce the risk or bromide drag. This has the effect of restarting the highlight development, but the effect is so small - and so quickly depleted - it doesn't seem to affect highlights visibly at all. That is, this doesn't cause highlight cooking or blocking.
In the image above, the scene was mostly just a muddle of gray with just a hint of some light reflecting off the green basil leaves. In that image, pretty much everything was a "middle tone" and the semistand development pushed slight difference in middle gray apart further to get the effect you see.
I wrote at some length on my explorations in low/no agitation techniques, here:
https://gitbucket.tundraware.com/tun...nd-Development
P.S. If you are familiar with H/D curves, another way to think of this is that it moves the left end of the curve lower and/or to the left. It increases the slope (gamma) of the curve in the middle, and it flattens the right end of the curve. You can actually fiddle with a digital monochrome image in an editor like GIMP or Photoshop to see the same effect.
Bookmarks