From: Randall Webb (randall.webb@lineone.net)
Date: 05/21/00-07:49:19 AM Z
I'm interested to see that there are a few people out there who still subscribe to the " if it looks right it is right" school of photography.Whatever happened to test strips or in the case of large format, exposing several sheets and developing them for different density ranges? My densitometer has developed a nervous seizure at present and reads zone V values at anywhere between 0.1 and 3.9 but I don't really mourn its passing.I have a set of 10x8 negs that I took a few years ago with the envelopes carefully marked ND 1.6, 2.1, etc but it doesn't make much difference to the final image. In fact the high contrast negs make very respectable gum prints.I also have a Stouffer strip but I never use it as I don't like a set of reducing rectangles on the bottom of the print.
On the same subject there is a little known historical fact which may be of interest.Hidden in the dark recesses of the Fox Talbot museum at Lacock UK there are the remains of what appear to be Fox Talbot's early experiments with a densitometer.It consists of an oil lamp, a concave mirror, some pieces of brass telescope and microscope, some string and a lot of sealing wax.A note (undated) in Talbot's handwriting is with it. I quote the contents of the note. " I have been excercised of late with a small experiment.The purpose of which is to measure the passage of light rays through the various areas of darkness on what my dear friend Sir J Herschel calls my "negatives". I had in mind a method reducing both the labour and the lack of consistency of making my salted paper prints.
However, I feel I shall be obliged to abandon this scheme as it is neither art nor science.It was my intention to work in conjunction with my good friend Sir John H. but he has been pre-occupied with his new "ferro-prussiate" process.
I was frustrated in my efforts on two counts. In the first by virtue of the fact that the rays of light were of with an office
punch in two white cards. Put one hole over the area you want to "match"
in the step tablet, then run other hole over the print until it matches
(or vice versa). The human eye is SURPRISINGLY sensitive in this kind of
matching -- in fact early densitometers relied on operator matching tones
by eye.
Judy
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