Film-Dev.Testing Methodology

[magic823]

I'm about ready to begin a big film-developer test. My goals are as follows:

Test most of the major films with most of the common (and semi-common) developers.
Test each of the combos with different development methods, i.e. tank, tray, jobo, tube, and machine.
Test normal agitation, continuous (jobo), semi-stand and stand development.
Create curves for N, N- and N+ and times (visible light and UV).
Create micrographs of grain and edge effects for comparisions.
Publish said curves, photos and timings.

Here is the equipment available:
EG&G Mark VII sensitometer
GAM Color densitometer
Xrite 361T UV densitometer
Jobo CPP processor
Wing-Lynch Model IV processor
And assorted tanks & trays.

I think I have a methodology figured out, but I want to see if I'm on the right track. So what I'm asking is other peoples ideas of how they would carry out said tests, what film-developer combos that they considered essential, and any other ideas.

I have a sponsor for the chemistry. I'm about ready to contact film suppliers to see if they will donate film for the testing. Wish me luck, this is a hugh project for me. Hopefully I'll soon have results to show everyone.

Thanks,
Steve

 

[pentaxuser]

Can't help with methodology. I am too inexperienced in this but would eagerly await your results especially the visual evidence. While I value the varied threads and comments we see in APUG, these sometimes fall into the category of conversations as opposed to education and are entertaining rather than of text book value.

The results of your project is the kind of thing I hope to get from APUG membership. The very best of luck.

Pentaxuser

 

[ann]

we do a class once a year doing something similar.

The students test at least one film from each speed category. We provide the following developers, HC110, Rodinal, Micophen,Acufine, Dianfine, Xtol, Perceptol and FG7.

They can test as many film types as they like.
We first determine the EI for the film along with the correct development times, reading the densities using a Heiland.

After they have determined their personal times, they then take a roll of each speed type and shoot a photo of the same subject matter, to include; landscape, portrait, architecture, still life and anything else they choose.

Then they make a print from each film type and each subject matter and we compare then side by side.

When finished they have their own personal "black book" of what a particular developer and film type will do for which subject matter type.

The next quarter we offer a paper class , basically doing something similar with papers and paper developers. Taking one negative and printing it on a wide variety of papers with about 15 different developers/or ratios of developers.

 

[sanking]

I'm about ready to begin a big film-developer test. My goals are as follows:

Test most of the major films with most of the common (and semi-common) developers.
Test each of the combos with different development methods, i.e. tank, tray, jobo, tube, and machine.
Test normal agitation, continuous (jobo), semi-stand and stand development.
Create curves for N, N- and N+ and times (visible light and UV).
Create micrographs of grain and edge effects for comparisions.
Publish said curves, photos and timings.

Here is the equipment available:
EG&G Mark VII sensitometer
GAM Color densitometer
Xrite 361T UV densitometer
Jobo CPP processor
Wing-Lynch Model IV processor
And assorted tanks & trays.

I think I have a methodology figured out, but I want to see if I'm on the right track. So what I'm asking is other peoples ideas of how they would carry out said tests, what film-developer combos that they considered essential, and any other ideas.

I have a sponsor for the chemistry. I'm about ready to contact film suppliers to see if they will donate film for the testing. Wish me luck, this is a hugh project for me. Hopefully I'll soon have results to show everyone.

Thanks,
Steve

Steve,

This is a huge project. Just testing all of the common films with one developer and the various methods of agitation would be a big project. In Spring 2003 I tested most of the films available with Pyrocat-HD and just one method of agitation, rotary, and that by itself was a rather large project.

I am wondering how you plan to plot the data? Is there a commercial program available that will run on Excel? If so, you can get a data transfer cable that will send your densitometer readings from the 361-T diredtly to an Excel spread sheet.

Sandy

 

[magic823]

I plan on writing the program myself to plot the data.

Yah, its a big project, but I hope to learn lots do it (and return something to all the people that have helped me learn). Its the reason I bought the sensitometer. BTW Sandy, I found your magic brush. It was in the red darkroom in the dish drainer. Still looks fine, although the handle has seen better days. Send me your address and I'll send it to you.

Steve

 

[PeterB]

I'm about ready to begin a big film-developer test....

Steve,

did you say big?

I would say Mammoth!!

You are about to embark on a very time consuming endeavour. The only motivations I can glean from your posts are that
i) You hope to "learn lots doing it", and
ii) "return something to all the people who have helped you learn"

So clearly there seems to be no monetary motivation, in fact unless you are donated the film, then I estimate that you'll be $7,200 out of pocket
[*]. You will also need to find a spare 1.5 years FULL TIME (working 8 hours a day) of your time [**] to complete the job.

Are you really that thirsty for this knowledge? Are you really that altruistic?

Just wanted to put things in perspective for you!
regards
Peter

[*] Assuming your choose 12 films (two each from Ilford, Kodak, AGFA, Fuji, Maco, Efke being major manufacturers), 6 developers (one from each major manuf. above), 5 different development methods (as you proposed), and 4 different agitation methods (as you proposed) results in 12x6x5x4=1440 rolls of film. At approximately US$5 each will cost $7200 in total.

[**] Assuming it takes on average 3 hours to expose, process, dry, cut, measure and document each combination, with 1440 rolls to test this will take
4320hours=540 x '8 hour' working days days=1.5 years with no holidays!

 

[sanking]

I plan on writing the program myself to plot the data.

Yah, its a big project, but I hope to learn lots do it (and return something to all the people that have helped me learn). Its the reason I bought the sensitometer. BTW Sandy, I found your magic brush. It was in the red darkroom in the dish drainer. Still looks fine, although the handle has seen better days. Send me your address and I'll send it to you.

Steve

First, thanks for the brush. Address is 136 Stonegate Court, Easley, SC 29642.

About the testing, iI would highly recommend that you look very carefully at Phil Davis' BTZS system before you settle on your methodology. In my opinion there is no other system of testing that gives you a bigger bang for the buck. In essence, you simply expose a few sheets of film to a reliable light source (your sensitometer fulfills all expectations), and then develolp the film by for different times in individual tubes by rolling them in a water bath. When you plot the data from these tests you have reliable information about EFS as well as N and SBR for this film/developer combination. If you test very carefully in terms of time and temperature, and the method of rolling the tubes, you will get excellent comparartive data about any film/developer combination.

Sandy

 

[magic823]

I have BTZS (alsong with his video) and it is the basis for my testing methodology.

I also have the Wing-Lynch processor (with a nitrogen burst system) to automate a lot of the basic work. But to be truly useful I think we need to know how everything reacts with other agitation methods.

I know its a massive project and I know its going to take awhile to complete. I hope at the end to have the definative resource for film development (and hopefully a book or at least a few mag. articles.) I may even come up with a workshop for the Formulary on calibrating your system.

Sandy, I'll get your brush send this Thursday, since I'm headed to San Francisco (Mountain View actually) to teach till then.

 

[magic823]

Steve,

did you say big?

I would say Mammoth!!

You are about to embark on a very time consuming endeavour. The only motivations I can glean from your posts are that
i) You hope to "learn lots doing it", and
ii) "return something to all the people who have helped you learn"

So clearly there seems to be no monetary motivation, in fact unless you are donated the film, then I estimate that you'll be $7,200 out of pocket
[*]. You will also need to find a spare 1.5 years FULL TIME (working 8 hours a day) of your time [**] to complete the job.

Are you really that thirsty for this knowledge? Are you really that altruistic?

Just wanted to put things in perspective for you!
regards
Peter

[*] Assuming your choose 12 films (two each from Ilford, Kodak, AGFA, Fuji, Maco, Efke being major manufacturers), 6 developers (one from each major manuf. above), 5 different development methods (as you proposed), and 4 different agitation methods (as you proposed) results in 12x6x5x4=1440 rolls of film. At approximately US$5 each will cost $7200 in total.

[**] Assuming it takes on average 3 hours to expose, process, dry, cut, measure and document each combination, with 1440 rolls to test this will take
4320hours=540 x '8 hour' working days days=1.5 years with no holidays!

I plan on where possible using bulk rolls and using my automated processor to help on the time.

Yes, I know it will take time and money. Hopefully I'll get most of the film donated. I have a contact thats helping work on that.

The bottom line for this for me is will it be useful to have this information available? And so far, everyone I've discussed it with says yes.

Think of it was the massive film development site on steroids with charts and photomicrographs (but in book form). The last word in B&W film development.

Steve

 

[Jorge]

The bottom line for this for me is will it be useful to have this information available? And so far, everyone I've discussed it with says yes.

Steve

Perhaps they dont want to be rude? You say you have the BTZS, have you seen the data Phil provides with the plotter? I have not counted them, but there are at least somewhere in the neighborhood of 85 files and this is only for tube developing and he is missing the forte and bergger films.

Assuming you will calibrate your thermometer, sensitometer, light source for each and every run, and are able to keep the appropriate variables constant. The moment someone wants to use your results with different settings for the variables your results are no longer valid, and this does not take into account water quality and things like uncalibrated thermometers.

I really see not usefulness to a project like this, even those of us who rely on sensitometric data will not take your word for it. For example, to calibrate my system for the BTZS with Phil's data I had to use different development times to obtain the same results he did with my film of choice. Who knows why the differences? but there must be a reason why his data and mine did not compare when using the exact same settings, I suspect something similar will happen with your results. Even with mechanized development, your results will apply only to you. Yes, they might serve as a reference, but that is all.

Besides, with a project of this magnitude, I am afraid by the time you are done, some of the films you tested will no longer be available......

I dont want to rain on your parade, but really, I think you would be better served making pictures instead of step tablets......

 

[photobackpacker]

You are well equipped on the development and densitometry side. While you haven't mentioned it, how will you expose the film? One of the most difficult tasks for me is obtaining an evenly lit test target that retains it's lighting levels with great consistency. I finally resorted to making a "rim light" arrangement with 4 - 100 watt Reveal bulbs (a higher color temp than regular bulbs.) I mounted these in the four corners of a board that has a hole in the center through which I can shoot. This has removed the evenness variable and the change in intensity of these bulbs over their life is not a factor during the relatively short duration of a film testing session.

Even though the Reveal bulbs are not a full daylight color temp (~5600+k), they seem to be close enough where I can see no difference in film response in daylight and even full-shadow - blue sky conditions (9000k ++.)

Pay close attention to the response you get from TMax. With your obvious interest in development control, I think you will find this film to be loaded with potential and a good match for meticulous personality.

 

[sanking]

I really see not usefulness to a project like this, even those of us who rely on sensitometric data will not take your word for it. For example, to calibrate my system for the BTZS with Phil's data I had to use different development times to obtain the same results he did with my film of choice. Who knows why the differences? but there must be a reason why his data and mine did not compare when using the exact same settings, I suspect something similar will happen with your results. Even with mechanized development, your results will apply only to you. Yes, they might serve as a reference, but that is all.

My experience is somewhat difference. I find that if I follow closely all of the details involved in Davis' BTZS method of testing, the data from my files is remarkably close to the data in his samples for any specific combination of film/developer.

Likewise, I fully expect that if someone takes my own data and repeats the conditions of the test they should come up with results very similar to my own. There are many reasons why one might not come up with the same results, but with very close control of the materials and the testing conditions there should not be much difference in results.

Sandy

 

[sanking]

You are well equipped on the development and densitometry side. While you haven't mentioned it, how will you expose the film? One of the most difficult tasks for me is obtaining an evenly lit test target that retains it's lighting levels with great consistency. I finally resorted to making a "rim light" arrangement with 4 - 100 watt Reveal bulbs (a higher color temp than regular bulbs.) I mounted these in the four corners of a board that has a hole in the center through which I can shoot. This has removed the evenness variable and the change in intensity of these bulbs over their life is not a factor during the relatively short duration of a film testing session.

Even though the Reveal bulbs are not a full daylight color temp (~5600+k), they seem to be close enough where I can see no difference in film response in daylight and even full-shadow - blue sky conditions (9000k ++.)

Pay close attention to the response you get from TMax. With your obvious interest in development control, I think you will find this film to be loaded with potential and a good match for meticulous personality.

Bruce,

Steve is using a sensitometer. That is his exposing system.

Sandy

 

[Jorge]

Likewise, I fully expect that if someone takes my own data and repeats the conditions of the test they should come up with results very similar to my own. There are many reasons why one might not come up with the same results, but with very close control of the materials and the testing conditions there should not be much difference in results.

Sandy

There are many reasons why results can vary, a uncalibrated thermometer, water quality variations and composition, rotation speed and developer oxidation, etc. Not everbody has consistent temperature control or access to destilled water, and even so, I have rarely seen destilled water that is all uniformely 18 Mmhos resistance, so even within treated water there are variations.

Why tests if what you are aiming too is "not much difference?"

In any case, your experience is different than mine, lets leave it at that. OTOH I would rather grow and become a better photographer by spending the 2 or 3 years making photographs than step wedges, but to each his or her own. If Steve wants to spend all this time, money and effort to do this, that is his choice, I just dont see the usefulness when there are sites like digitaltruth that have a lot of this information already. As to edge effects, sharpness, etc. This once again is IMO relative to the tester and his results. Didn't you and some other guys in this forum had a thread on edge effects that went on forever and you all never agreed?

IMO testing should not be the end goal but a stepping stone to better photography, but hey, I am not doing it....so have at it..

 

[Kirk Keyes]

Test each of the combos with different development methods, i.e. tank, tray, jobo, tube, and machine.
Test normal agitation, continuous (jobo), semi-stand and stand development.
Create curves for N, N- and N+ and times (visible light and UV).
Create micrographs of grain and edge effects for comparisions.
Publish said curves, photos and timings.

I think I have a methodology figured out, but I want to see if I'm on the right track. So what I'm asking is other peoples ideas of how they would carry out said tests, what film-developer combos that they considered essential, and any other ideas.

Don't worry about film/developer combos at this point - you need to come up with a written Standard Operating Procedure for this before you do any testing. Then let us read it and ask opinions then.

So I would suggest that you write out your proposed testing procedures - step by step of each method. Be as precise in describing step of each method. And by doing this, you will have hopefully eliminated some of the possible variables that you may run into. This is really the only way we can help you figure out if you have come up with a suitable method of testing.

I realize that you are being very general in your post above, but as an example of amibiguity - are you really going to process each film at it's N-1, N, and N+1 contrasts? Or are you going to generate a family of film curves that are based on standardized times to determine the times for N-1, N, and N+1? Is N-1 and N+1 enough? Perhaps you should also include N-2 or 3 or N+2 and 3?

So will you start out processing a given film/dev/agitation combo at 5, 7, 10, 14, and 20 minutes at a particular temp (and which temp - and why did you choose that temp?) to build a curve family. Then you crunch some numbers - and then you find out that N-1 = 7.8 min, N=9.4 min, and N+1 = 12.1 min (as an example). So then are you going to go back and then do a runs at 7.8, 9.4, and 12.1 minutes to verify your calculated times?

And if you do those 3 (or more) verification runs - how close is close? If you pick your CI of N to be 0.58 (side note: what where the reasons for picking that value?), is a CI of 0.55 good enough? Or is 0.57 good enough? What about 0.61 or 0.59? Or do you need to get 0.58 for your tests?

And then do you go back at a later date (days or weeks later) and then verify that you can get a CI of 0.58 with your time of 9.4 minutes using that same film/dev/agitiation/temp combo? You probably should try to to build some certainty into your testing scheme.

What about things like do you start the development time when you start to pour the developer into the tank or when you have added the last drop? I feel that one way is better than the other.

How about things like what density will the film be that you use to measure the graininess and take your microphotographs? What are the targets you are going to be using to measuring edge effects. How much difference in exposure are you going to use to test the difference there is between edges? How are you going to measure them?

Do you have calibrated equipment - densitometers, sensitometers, timers, thermometers? How recent was the calibration? How accurate are your measurements?

These are just a few of the kinds of questions that you need to have answered before you start a project this big. Especially if you don't want to spend a lot of time and resources redoing stuff because you are getting data that is conflicting or just not making any sense.

It may seem like a big undertaking to write all this out - but you will be soooo happy that you did when you finish the project. And if you do write this all out before testing - you will already have the first several chapters of your book written!

Finally, I would like to offer my thoughts and opinions on any testing Standard Operating Procedure that you come up with if you like.

Kirk - www.keyesphoto.com

 

[bjorke]

BTW, to speed you up a bit check out http://www.flickr.com/groups/bw_film-dev_combinations/

but be aware that ANY scanned image on the internet is only a hint in the direction of what the prints and negs will REALLY look like