Response to Tweaking PanF/Rodinal

> incandescent bulb

OK, you have a condenser enlarger.

This means a couple of things....

You'll need to develop your negs to generally lower contrast than those who use a diffusion enlarger. Not tremendously so; the difference is a 10% to 20% reduction in development time.

A silver neg printed with a condenser head is subject to a phenomenon called the Callier effect. This is a disproportionate decrease in transmitted light compared to increasing density.

That certainly doesn't mean the condenser head isn't any good. It just means you need to compensate for it.

In the old days that compensation sort of took care of itself; films had what's called a shoulder in their curve shape. Or iow, the rate of density increase was _lower_ than the rate of exposure increase.

So the effects essentially canceled each other out.

Modern films usually have no significant shoulder in most common developers until an extremely wide range has been spanned. I routinely find HP5+ and Delta 100 to have a pretty much straight curve shape through the 14-stop range I test for.

The result of using a modern straight-line film and a condenser head is often highlights that are a bear to print simply because the already-dense highlights are made apparently (to the paper) even denser by the Callier effect.

So what can you do about it?

Some will suggest buying a diffusion head such as a dichro or cold-light; either would avoid the Callier effect although imho a dichro makes a lot more sense.

But don't go spending money yet.

Try using a modern-style paper such as Ilford Multigrade IV. This type of paper has been developed to accomodate the newer types of film; for the same exposure time and normal shadow and midtone densities, you'll get a little more highlight density.

You'll still probably have to burn in those highlights. Nothing wrong with that, really; just about all prints need to have some burning or dodging.

So try burning the highlights with a #0 filter, not enough to make them go grey but just enough to get a slight texture so it's not all paper-base white.

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