Archived posting to the Leica Users Group, 2001/06/12

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Subject: Re: [Leica] V35 Enlarger With Color Module Newbie Questions
From: "Greg J. Lorenzo" <>
Date: Tue, 12 Jun 2001 23:31:58 -0600
References: <> <008801c0f355$f76c1800$>

My thanks go out to all who replied to my questions on this enlarger:
Bob, Pascal, Mitch and Dan.


Greg J. Lorenzo
Calgary, Alberta 

Dan Post wrote:
> Greg-
> If you are using the color head to print variable contrast paper, allow me
> to make a suggestion. I'll preface my remarks by saying that having had a
> step-tablet, the same one for twenty five years or so, really is not that
> major an expense, even if you buy the outrageously priced Kodak version, and
> I have seen them offered on the internet for as little as about $20 for a 21
> step tablet. I also made the investment in a used Beseler Color Analyser,
> some which I have bought for as little as $50 dollars, and then sold to
> friends who I taught split printing to (at cost, by the way!!)
> If you use Ilford paper, they have a 'guide' where the approximate steps of
> contrast are shown with the approximate settings of the color head. As you
> note, I said 'approximate' since the color heads' calibration is anything
> but exact, and you would need a densitometer- or enlarging meter! to
> determaine with any accuracy the true density of any filter setting.
> What I did was to use each of the settings given, and exposed a strip of
> paper with a step tablet on top using each 'grade' of filtration,
> developing, then seeing what the actual contrast grade turned out to be.
> Since a step tablet like the one I use is divided into 21 steps of density,
> eachone about .15 absolute optical density more dense than the previous, it
> gives a fairly wide range of possibilities. IF you think of it as a negative
> developed to a contrast index of .5 then each step represents one stop of
> difference in theoretical illumnation of a scene- and could be considered a
> 'perfect' negative since it captures all the possible tones you might
> encounter in a one strip.
> So if you find that there are seven bars of gray on your test strip, then
> you know that the absolute range of that particular filter setting is seven
> times .15, or .75. This translates into a density range of .75- from the
> darkest printable shadow to the lightest detectable highlight!
> Simply adjusting the filtration either more yellow or more magenta will
> alter the overall 'grade' and you can very easily adjust the filtration to
> give you the exact 'grade you want. You can plot several settings on a chart
> and extraploate to find the exact contrast grade you want.
> Cyan is very little used, but if you want to use it, it makes little
> difference- Cyan and Yellow makes a green light, typically you think of it
> as about 562nm wavelength, and the Cyan and Magenta make Blue- the exact
> wavelength escapes me, but I think about 450nm. The low contrast emulsion is
> senitive to the green, and the high contrast emulsion is sensitive to the
> blue. Varying the two will make the VC paper respond in almost an infinite
> number of possible grades within the range of its sensitivity.
> Usually, I can count on Ilford Multigrade to give me a range of three steps
> at the highest contrast setting to about eleven with the lowest- that means
> that a negative with a density range it from .45 to 1.65 is printable,
> though that is 'pushing the envelope, and I rarely have negatives that
> extreme unless I am doing either very low light work, or sometimes what is
> called 'high key' portraiture (little girls in white dresses, sitting in a
> white rattan chair with a white backgound, holding a white teddy bear or
> kitten!!).
> Once you have 'calibrated' you can then get very controlling as to what, and
> how you print. Once you sttle on a good paper/developer combination, you
> will be an unbeatable printer, and find that you waste a lot less time and
> material getting what you want!!
> Just my .02 worth!
> Good luck, and best of multicolored light to you!
> Dan

In reply to: Message from "Greg J. Lorenzo" <> ([Leica] V35 Enlarger With Color Module Newbie Questions)
Message from "Dan Post" <> (Re: [Leica] V35 Enlarger With Color Module Newbie Questions)