D-23 Strength - Portraits

[Flauvius]

For those that use D-23 with portraits of subjects with caucasian skin, and a SBR of 5-7, is there any distinction between using D-23 1:1, or at working solution strength?

Also, under the referenced SBR criterion, how does the working strength of D-23 impact upon black/olive skin tones?

Thanks,

Flauvius

[Ken Lee]

http://www.kenleegallery.com/images/forum/ExposureAndDevelopment.png

With film, we expose for the low values and alter development to control the high values. This principle applies not only to portraits, but also to landscapes and still-life: every type of subject.

With greater dilution, longer developing times are required to achieve the same amount of contrast. Conversely, a higher concentration of developer gives higher contrast unless we shorten the developing time accordingly. This is true with almost all developers: there's nothing special about D-23 except that it has only 2 ingredients and is therefore a bit easier to prepare from scratch than more complicated formulas, and possibly cheaper. It certainly becomes cheaper when we use it 1:1 instead of full-strength.

We are far more likely to notice even slight mistakes of exposure and development in portraits, because our perception of human faces is very keen. That's why it can be helpful to include a human model when testing film speed, lighting and equipment.

[Flauvius]

Ken:

Are you in fact saying, when operating with a SBR of 5-7 in a portrait setting, there is no difference between D-23 at 1:1, and D-23 at working solution strength, for negatives that are developed to the same contrast grade? The focus of my interest and question is the impact of D-23 solution strength upon shadow detail, and where grain size in not an issue with a 4x5 negative printed to 8x10 - 16-20.

While I appreciate Fred Picker's general photographic attitude, "Just try it out, and see what happens", I hope that someone who has extensive experience using D-23 for photgraphing people with white or black skin will share their insights as I begin to explore the nuances of this developer.

Flauvius

[Ken Lee]

This may sound like an over-simplification, but if we're concerned about getting adequate shadow detail and/or not blowing the high values, we may need to perform some film testing to determine effective film speed and developer times for our specific film/developer combination - or simply give more attention to how we meter the scene.

Once those steps are taken, underexposure and over-development only happen as an occasional mistake, whether the subject contains skin or any other material.

For portraits, it might be more helpful to investigate the spectral response of different films, and how people look under different colored lighting, filters, etc. Given adequate exposure and development, those factors may have a greater influence on the nuances of rendering than a comparatively modest change in developer dilution.

[Rod Klukas]

This may sound like an over-simplification, but if we're concerned about getting adequate shadow detail and/or not blowing the high values, we may need to perform some film testing to determine effective film speed and developer times for our specific film/developer combination - or simply give more attention to how we meter the scene.

Once those steps are taken, underexposure and over-development only happen as an occasional mistake, whether the subject contains skin or any other material.

For portraits, it might be more helpful to investigate the spectral response of different films, and how people look under different colored lighting, filters, etc. Given adequate exposure and development, those factors may have a greater influence on the nuances of rendering than a comparatively modest change in developer dilution.
As Ken said, some testing is best. D23 works best when not diluted and kept in a Dark Glass bottle. when the initial batc, say 1 gal is mixed in the bottle, mark the level of the chemistry. Next, make up a Glass bottle of DK25 for replenisher. Each time you use the D23, return it to its original bottle, and note if the level is below the line. If it is below add DK25 until back to the line. This replenishes the developer.
When you run out of DK25, just make more of that.
This will over time get better and will yield wonderful negatives especially with thicker films such as TriX and HP5+/Fp4.
I have even achieved plus 5 expansions on non portrait situations, but wonderful skin tones as well. about 1 to 1-1/2 ISO loss in speed.
The developer and repleneisher will last for years getting thick with silver in the bottom. I use brown bottles but still keep it in a closed cupboard. I had my first batch for 25 years-dropped bottle-yikes!
New batch still cooking at 10 years old.