BTZS Testing: Pyro Negative, Silver Paper which step tablet

[Gary-M]

I'm using the BTZS system and Plotter for Windows.

I have begun film and paper testing via BTZS. The first phase of this adventure will be using Pyrocat-HD with FP4+ (4x5) and printing on MGIV VC. I have two Stouffer 21 Step tablets. I calibrated one for the film testing which will be complete in a couple of hours. I used a X-Rite 361T to read the stained test negatives.

I am now ready to do the paper testing. Should I use the same step tablet values (UV readings) for the paper tests or should I use my Heiland densitomter to calibrate the step tablet for paper? Will this distort the matching in the BTZS Plotter for Windows program?

Thanks,
Gary

 

[Jim Noel]

Gary,
I don't know about your situation since I do not like or use BTZS.
That said, I found when I moved to Pyrocat HD it was necessary to make my own step tablets developed in pyrocat in order to get accurate film speed and development time tests.

 

[Gary-M]

Jim,

I was wondering about that. Then you used the stained step tablets for both your film and paper?

Now that I think about it, my question was not phrased well. Of course I have to use the Heiland for paper because it is the only one that can read in reflection mode. I guess my question should have been whether to use the step tablet calibration I did in UV mode or do another in standard mode.

Gary

 

[Robert Hall]

Phil would smack you up side the head and tell you that you can't do BTZS with pyro.

(I use the uv for platinum printing and the normal for regular silver printing).

 

[Gary-M]

Robert,

I enroll in an on-going large format class here. My plan was to do silver printing of pyro negatives this Fall semester and then try some Pt/Pd in the Spring. I've done some silver printing from pyro negatives and am very impressed with the results. I just guessed at the development that time, but now want to try a more scientific approach.

I know they don't like to promote BTZS for pyro, but I had the impression that Sandy King and others were at least using the measurement and analysis part for film testing.

Gary

 

[MVNelson]

BTZS

Robert,

I enroll in an on-going large format class here. My plan was to do silver printing of pyro negatives this Fall semester and then try some Pt/Pd in the Spring. I've done some silver printing from pyro negatives and am very impressed with the results. I just guessed at the development that time, but now want to try a more scientific approach.

I know they don't like to promote BTZS for pyro, but I had the impression that Sandy King and others were at least using the measurement and analysis part for film testing.

Gary

A lot of BTZS'ers use pyro developers and even have very nice curves stored on our palm pilots ready for use...it turns out that if you have a densitometer with a blue light channel you can read your films and make your curves and they will be good for silver printing...on the other hand you must have a uv reading densitometer to read those same films for pt/pd (uv exposed processes)...there are wonderful articles on this @ unblinkingeye... My favorite combos are for LF Tmax400/pyrocat-mc (Sandy actually "lent" me his curves for uv which were so good I haven't made my own )and Delta100/prescysol-ef for MF both semistand development...( its so cool col to see precise curves for stand and semistand plotted out for times from 10 to 60 minutes)...turns out these developers fit in perfectly with BTZS use...you don't need to be making step tablets or jumping through other hoops....I encourage you to persue this the results will be well worth the efford!....

Miles

 

[MVNelson]

oh I forgot, you can do the paper test just like in the BTZS book...
matcher/plotter will work the same....

Miles

 

[gainer]

Frankly, I don't see why one cannot simply contact print the negatives on the paper you intend to use and count the number of steps that show. That shows you directly the contrast index for that particular development as it applies to that type and grade of paper. You only need one gray scale, and the densities that show on the print of it on film are log relative exposure. You should expose the film so that at least one of the steps of the scale is at base + fog. Make the print of that negative on paper so that the first step that appears on film is just less than maximum black on the paper.

 

[Gary-M]

Interesting! I'm going to try it when I get back to town. I followed Phil's instructions and put a piece of tape on the step wedge, so each negative has a measurable area that is at FB+F.

Gary