Film Testing Without a Densitometer

**Brian Ellis** · 5-Dec-2005, 17:32

"Hutchings has an idea but I do not have access to the book. Does his method require a densitometer? If not what is the method?"

I'm not sure what idea you're talking about but Hutchings does discuss use of a densitometer on p. 65 of "The Book of Pyro," if that's the book you're thinking of. However, he doesn't say it's required for anything. He says "there are many different methods of testing film," as there obviously are. He then goes on at some length to describe a method but I haven't used that method and couldn't summarize it here.

**Joe Smigiel** · 5-Dec-2005, 17:55

OK. You want to test sheet film for EI without a densitometer, here's the easiest cheap route. Buy a wratten #96 0.10 neutral density filter.

Load a sheet film holder with your film, point the camera at an evenly-toned wall at infinity focus (to eliminate extension factor) in even light. Take a reflected meter reading of the wall being sure not to cast a shadow on it. Use the manufacturer's ISO rating for the first sheet test. Pull the darkslide halfway out and make an exposure 4 stops less than indicated by your meter.

Develop the film. When dry, put it on a light box and place the ND filter on the part of the film that didn't get exposed adjacent to the exposed part. If the density appears the same, voila, you have your film speed point of 0.10 net density above film-base + fog density.

If the filter is denser, lower the ISO and run the test over. If the filter is less dense, increase the ISO and run the test over. Repeat until the filter on the film matches the exposed portion. At that point you now have the film EI for the equipment you've used and the process you've applied to the film.

You have now determined the proper EI ala Picker or Adams without using a densitometer.

Doesn't mean that EI will give you the best print quality or that your development is proper, but at least you have the standard starting point being discussed in the Zone System texts of various authors. Nuances and proper development rely on testing the other end of the scale and doing paper tests.

To get the proper "N" (N-, N+, etc.,) development time you have to make choices about your personal visualization of the zones and know the response of your paper. By this I mean are you going to call zone IX white, or zone X white? In other words, (using that evenly-toned wall again as subject) is the highlight threshold 4 stops above the indicated meter reading, or is it 5 stops above? Makes a difference. Once you determine that, then you can start testing different highlight exposures and developments and see how they interact with the paper to give you predictable highlight print values. You really don't need a densitometer to do this. You just need to print the tests at the standard minimum time that gives you the effective maximum black of the paper as described by Picker and others (i.e., the "proper proof" time). At that time your 0.10 net density sheet should print just slightly lighter than maximum black and you should be able to test for highlight thresholds visually at the other end.

Matching the numbers stated in the books isn't going to get you there. It may only get you close. However, comparing your film to known values on a 21-step transmission density wedge will probably get you there quicker, and a lot more inexpensively.

**Joe Smigiel** · 5-Dec-2005, 18:27

OK. Now here's the rub with Picker. After advocating all that "proper proof" stuff and EI based on the 0.10 density above fb-f, he goes off in his Zone VI newsletter, #51, June 1987, page 7: "I found myself constantly breaking both the 'expose for the shadows' rule as well as my own modification. It finally dawned on me that when I made two exposures of a subject (to be absolutely sure I had enough exposure) the 'overexposed' one always made the better print. Right? The best negative is the one that places all values as high as possible without blocking. So I began to consistently place the high value on zone VIII, regardless of where I wanted that value to end up in the print."

So first of all, he's now bracketing and secondly, he abandons the strategy of printing with an eye turned towards maximum black. He basically adopts Mortensen's system by doing this new MPD ("Maximum Printable Density") modification of the zone system.

He further states: : "I always expose for the maximum printable density, except sometimes, I expose less when I know I want a large contrast increase. To increase the contrast, I place the high value on VI-and-a-half (rather than VIII) and develop plus one-and-a half."

Sure sounds very similar to Mortensen's "7D negative" to me.

And why in the first place is any emphasis ever placed on maximum black proofing when SOP is to "print for the highlights"? Add to this the fact that proof sheets print with less contrast than with condenser enlargements, and the whole maximum black target loses its practicality IMO.

I just picked up a copy of Arentz' book and am looking forward to reading it as I suspect it address this issue and also help crystallize the BTZS approach outlined by Davis.

**sanking** · 5-Dec-2005, 19:06

Joe,

Good points about Picker's comments about placement of shadow densities. I agree with his later assessment that for many processes, placing the shadow values higher on the toe than log 0.8 - .010 above B+F gives better separation in the shadows with most films. We tend to do this routinely in printing with alternative processes such as Pt./Pd., and it also works very well with AZO.

Have fun with Arent'z book. He studied with Davis and understands and applies BTZS better than anyone I know. It is important to understand, however, that when printing with alternative processes there are ways of controlling density in the highlights that are even more extensive than what is possible with silver VC papers. For that reason alternative printers tend to place more emphasis in exposing and developing negatives on where to place the shadows on the curve, and one the shape of the film curve, than on where highlight values fall. That is true because highlights can be easily controlled by contrast controls that are routinely used to expand and contract exposure scale.

In any event, BTZS is extremely precise, much more precise than Zone, and the testing is easier and takes much less time.

And you don't even have to use a densitometer. You can make the tests yourself and send them to the View Camera store for analysis.

**Robert Ruderman** · 6-Dec-2005, 09:16

Thank you all.

I was not expecting my questions to start such a debate among the community. I very much appreciate everyone's response and thoughts on my question.

I am still learning my way around the Zone system of exposure and was not sure how (or if) I could establish my personal EI and "N" without a densitometer. From reading the responses, the world has many opinions/ideas on this thought. And, much to my delight, there are at least a couple of references in this thread to try a test without a densitometer. I am also looking forward to Steve's upcoming article in View Camera (I had a copy of Picker's book in high school, but it was promptly borrowed by a teacher and never returned).

The cause for my question is that my current negatives are rendering way too much contrast. I want to keep things simple with respect to using the Zone system. I see the Zone system as a way to meter and help give a degree of confidence that the "range of light" that is in the scene can be fully accounted for in the exposure of the negative.

I want to go the simplest most effective route. I simply want to get in the right ballpark with respect to exposure. Remember, Ansel Adams said "The perfect is the enemy of the good". For me, the determination of a personal EI and "N" are necessary things to bring my negatives back into line and get some degree of predictability and control.

Thanks again for everyone's input,
Robert

**Hans Berkhout** · 6-Dec-2005, 15:09

Joe-Fred Picker's pre occupation with Zone VIII led to interesting debate with Howard Bond, in Photo Techniques mag.
Sandy- I take it that you mean to place shadows on IV - IV raher than III? Or expose for quite a bit higher than 0.1 over fbf for zone I. You wouldn't use ozne I for placement of shadows, but that's how I interpret your writing. Please correct me if I'm wrong.

**sanking** · 7-Dec-2005, 07:46

"Joe-Fred Picker's pre occupation with Zone VIII led to interesting debate with Howard Bond, in Photo Techniques mag. Sandy- I take it that you mean to place shadows on IV - IV raher than III? Or expose for quite a bit higher than 0.1 over fbf for zone I. You wouldn't use ozne I for placement of shadows, but that's how I interpret your writing. Please correct me if I'm wrong."

If what I said was not clear my apologies. What I mean is that with many films, certainly ones with long toe films such as TRI-X, I would give more exposure than the minimum necessary to place Zone I at .08-0.10 above B+F. This will in effect shift all Zones higher on the curve and give better separation in the shadows. . On the other hand, with films that have very short toe and long straight line, such as TMAX-100 and TMAX-400, this kind of slight over-exposure is not needed.