Fine Grain and Sharpness

The silver particles that make up the image are called grain.  The size of 
the grain is what we refer to as fine grain or not so fine grain.  A fine grain 
developer prevents these grains from clumping together and producing what appears 
to be large grains.  The grain we see in a photo is actually the spaces between the
grains on the negative.  The smaller these spaces the finer the grain. Improper film 
processing increases the size of the grain.

Sharpness refers to the acutance of the film.  High acutance developers give the
appearance of increased edge sharpness.  The sharper the grain is, the greater the 
acutance.  Softer grain gives the appearance of less acutance.  Acutance is also 
related to resolution

The film's ability to produce fine detail is called resolution.  It is determined
by both the camera equipment and the film.  The sharper the grain, the higher the
degree of resolution.  There are other factors besides grain and sharpness that
determine resolution. These are related to the camera equipment.

I hope this is not too foggy.

I think that John is correct when he says that Microdol-X rounds the edge of the
grain and gives the appearance finer grain with the loss of sharpness.

Normal Developers like D-76 produce a very sharp grain similar to a sharp point 
on a pencil.  Fine grain developers like Microdol-X  have a high sulfite content 
that has a solvent effect on the grain, sort of like rounding off the point on a 
pencil, resulting in a reduction in graininess. This is usually accompanied by a
reduction of film speed and acutance. There are exceptions to this, ie. Microphen.

POTA Developer might be a good developer for Copex and Fuji HR as it is usually 
used to develop Tech Pan for normal contrast for pictorial use. It is cheap and only 
has two ingredients other than water. The formula is on my web site.

For more info contact: destowe@pipeline.com

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