BTZS DR/ES for condenser enlarger

[ParkerSmithPhoto]

In BTZS terms, I am trying to find an appropriate DR for the negative, or ES for the paper (hope I have those correct) when using a condenser enlarger (Beseler 45).

Beyond the Zone System (3rd Edition), Page 37:

Condenser enlargers, however, tend to increase the effective negative contrast, so you'll probably find that you get best results by selecting a paper whose ES is somewhat greater than the negative DR.

Given that a diffusion enlarger requires a DR of 1.0, what number would I need to target? My goal is to fit to an Ilford MGWT or MGIV grade 2 paper, and err on the flatter side, as I'd rather go up in paper grades than down.

I'm trying to get some new tests completed, and already have some interesting Plotter data on Barry Thornton's Two Bath. Thanks.

 

[Bill Burk]

I have a chart (that chart Stephen Benskin gave me) that shows Paper Grade 2, Paper LER 1.05 for Diffuse Enlarger.

And it shows Paper Grade 2, Paper LER 0.78 for Condenser Enlarger.

 

[ic-racer]

You need to measure you own ES depending on the paper you want to standardize to and the system of image production in use. If you are going to use a pre-established number, you might as well just shoot box ISO and process the negatives based on the instruction sheet.

Specifically, in your case, you want to project the step wedge with your enlarger (mask the step wedge edges well) to get the ES for your chosen paper. ( http://btzs.org/Articles/Sensitometry Part 2.pdf ) Now you can match your negatives that ES number based on the various scene illuminations and increasing or decreasing development times.

Obviously if you use multigrade paper there are a multitude of possible matches for negatives and paper because you will have multiple ES and DR values to pair together.

If you are able to use the whole range of filtered contrast values for the MG paper, you can simplify your life. You can develop all your negatives to something around 0.7 and printing on multigrade paper and ignore the "N" stuff. Working through the BTZS is a good to do but only if you understand the basic sensitometry on which it is based.