Film testing

[Michel Hardy-Vallée]

Thank you, John.

 

[jd callow]

Thank you, John.

Your welcome

 

[Ray Heath]

Your welcome

yeh, thank you John

 

[timbo10ca]

What you say is essentially correct. BTZS matches paper ES to film exposure and development, but it does not concern itself with hardware, other than the issue of lens flare. BTZS testing does, however, give you a real true EFS (effective film speed). It is real and true because each user develops a personal speed point that is calibrated to a film and developer combination known to produce true box speed. From that point you run a test of five films, exposed the same and developed for different times, and when you plot those tests and record the values you know how to expose and develop your film for any SBR of N condition. To derive that amount of information from traditional ZS testing would take you days and days. That is why many people who continue to use ZS metering use BTZS testing methodology.

At that point you have the information necessary to take your equipment into the field and get accurate exposures, assuming that your equipment is within tolerance and you really know how to meter. Most modern equipment is quite accurate and the total accumulated error, even assuming that the lack of tolerances are all in the same direction, should not amount to over about 1/2 stop, which is well within the mar gain of error for exposure of film. If you have an older lens in a shutter of dubious reliability you obviously need to test it with a shutter checker and make allowances for field work. You should also calibrate your meter. The logic in this is that it is much easier to have one set of film exposure and development data that is true, and then adjust for lack of tolerance in specific components of your field system. Some ZS testers make the other case, that each combination of equipment should be tested in the field, but that would become a very onerous undertaking for people who own many different lenses and/or cameras. I think testing the individual components made more sense in the past when most photographers only owned and used two or three lenses, but nowadays many people own as many as 6-10 lenses for every format they use, and many people are working in multiple formats.

Reasonable people can debate the merits of the two methods of testing, but
at least there you have the logic.

Sandy King

I appreciate your assessment. I was going to make this "assumption", but I'm seeing that this continues to make an ass of.... well, you know.

Initially, I had been under the impression that mechanical variation was much more significant, hence the need for ZS testing (I mean, why else would so much be written on the subject?). I perceived this as a daunting task, as you say, having multiple formats and lenses. That's alot of testing. I see what you mean regarding the neccesity of old to do this, I suppose, but I'm not sure that I buy into it being negligible now- Was equipment less reliable? Was the understanding of the materials less?

I would have imagined that equipment variations would be more dramatic by far than what BTZS is testing. That is, we're only really individualizing the developer, if you think about it- There are 3 factors in BTZS we're standardizing:
1) film (exposure)- by my understanding, you are implying this is a minor variable, as today's equipment is quite reliable, and only requires fine-tuning in the field.
2) paper (and developer)- also a minor variable, because it is essentially developed to completion (unless you are trying to match to a VC contrast grade, but by my reasoning, as it *is* developed to completion, there shouldn't be much variation from manufacturer's information, if you keep temperature equal, and don't use some crazy agitation technique). Just how important is the lightsource/enlarger/timer anyway? It doesn't technically have a bearing on the film and paper (you just have to adjust time as necessary)- the tones are still going to be there on the print whether your timer is accurate or not.
3) film developer- the biggie. But really now.... Is my water that much different from the company's? If the directions say 6 1/2 minutes at 68 F, agitating every 30 sec..... Well, those aren't very demanding parameters to stay within. Why would development be that much different in my darkroom from the manufacturer's lab to cause such degrees in variation? I doubt that anybody can repeat *exactly* their development procedure every time anyway. I *do* see how a shutter can continuously missfire a half stop slow though.

I really don't see how this 3 part system is so individual, and why data sheets can't be used if personal equipment (which I would have guessed would be the major variable because personal quality control is not nearly equivalent to the manufacturer's) isn't even taken into the equation. I just can't see how the aspects mentioned in the first half of your statement can't be taken from the manufacturer. Obviously what you say is true, or there wouldn't be so many succesful photographs made with BTZS. Or are these being made by people who have bought in, and don't want to acknowledge their bias? Did they have to do a crap load of equipment field testing too, in order to get those prints? In an ideal closed system with pristine equipment, I can see how BTZS would be superior for getting better results faster, but I don't imagine there are many of those systems out there. Maybe just the straight ability to meter the scene and visualize properly is what makes the great print, regardless of if you use ZS or BTZS.... So many variables unaccounted for... What looks like the magic bullet on the surface is far from it.

Is it a matter of controlling every other conceivable variable that the camera and lens is negligible? Is BTZS truly doing this?

Is it just a matter of "well, you gotta start somewhere... with the ZS it's equipment calibration, with BTZS it's material calibration"?

Tim

 

[bogeyes]

How much tolerance and precision we need in our work is an important issue.

APUG is not a homogeneous community, even though we are united by an interest in traditional photographic printing methods.. On the one extreme we have folks who use exclusively 35mm and shoot only a few rolls of film per year, and have little or no financial interest in the process. At the other extreme are LF and ULF photographers who expose hundreds of negatives per year, many of whom derive income from their photographic activities. In between there are MF users.

My own belief is that if you are a LF or ULF photographer working with sheet film one should do whatever is possible to expose and develop the individual sheets so as to make printing as easy as possible. In the long run you will save a lot of time and aggravation by learning what you need to know to make negatives that print well. And since you are working with individual sheets of film it is a simple matter to expose and develop for each scene.

On the other hand, if you are a 35mm photographer any given roll of film typically will have negatives covering a fairly wide range of subject lighting conditions, and if that is the case optimizing development for the entire roll is impossible. My own solution to this situation is to use C-41 color negative film, expose for shadow detail, and just have the film processed at local lab. To make a B&W print you will have to either have the negatives put on CD or scan them yourself, but since highlight density of color negative film shoulders considerably a good scanner should be able to capture it, even if the subject has very high contrast lighting. To print you will have to adjust the curves with image manipulation software.. If this procedure interests you go over the hybrid forum and start a thread. I will say, however, that I have exposed medium format color negative film in SBR conditions of 10 or higher and was able to make prints with a full range of tones from the deepest shadows to the highlights. On the whole I find that this procedures is much more productive than shooting B&W film in the camera.

Sandy King

Sandy are you saying that the BTZS system is overkill for roll film when a wide range of exposures and sbr has to be covered?If so I agree.

 

[sanking]

Sandy are you saying that the BTZS system is overkill for roll film when a wide range of exposures and sbr has to be covered?If so I agree.

Why don't you say it? If you do, I won't disagree.

BTZS could be practical with 35mm or roll film if one were to expose all of the frames on the roll in scenes wtih the same lighting conditions. That is feasible, but not always practical.

Sandy

 

[bogeyes]

Why don't you say it? If you do, I won't disagree.

BTZS could be practical with 35mm or roll film if one were to expose all of the frames on the roll in scenes wtih the same lighting conditions. That is feasible, but not always practical.

Sandy

OK I have my blindfold on and I'm tied to a post waiting to be shot at. BTZS is overkill for roll film, but as you say could be usefull if the whole film was exposed in the same lighting conditions. I will add to that I think there is enough latitude in exposing and developing B&W film to produce B&W photographs ACCEPTABLE TO ME without using either the BTZS or the zone system. Fire away, all comments welcome but please shoot straight for the heart

 

[Paul Howell]

OK I have my blindfold on and I'm tied to a post waiting to be shot at. BTZS is overkill for roll film, but as you say could be usefull if the whole film was exposed in the same lighting conditions. I will add to that I think there is enough latitude in exposing and developing B&W film to produce B&W photographs ACCEPTABLE TO ME without using either the BTZS or the zone system. Fire away, all comments welcome but please shoot straight for the heart

The only I that I have used the ZS with 35mm and I think the same can apply to BTZS is bulk load in very short rolls 8 to 12 and treat each roll as you would a sheet of film.

 

[phritz phantom]

now there is something i don't understand. i read the two links about film testing that were posted before. at the beginning of the second article the author says something that i can't wrap my mind around:
"The photo is a full stop underexposed, resulting in a weak print with no true blacks. "
http://www.halfhill.com/speed2_1.html

how does that work? shouldn't underexposing give darker blacks (not possible, therefor black faster - at higher zones) than when exposing normally?
or is that an error in translation? to me: no true black = grey = more density
is there something fundamentally wrong with my understanding of the ZS? since he says somewhere that he does b/w testing for 15 years, so i assume it's rather my mistake than his...

 

[David A. Goldfarb]

It is possible to use BTZS or the Zone System or DBI for 35mm (you could carry a few different bodies or swap out rolls for different exposure conditions), but considerations of enlargability with small format are usually more important than nailing the exposure and contrast range on film, so for 35mm it's often better to target negs for grade 3 (thinner negs have less grain) under "N" lighting conditions, and adjust paper contrast as needed for most other conditions.

It would be beneficial to learn one of these approaches, just to see what they can do for you and to understand how to control tonality with exposure and development, and then decide for yourself how to balance the tradeoffs.

You might decide, for instance, that it's a false economy to insist on shooting 36 exposures before changing film, or you might start bulk loading shorter rolls, or you might decide that having two or three 35mm film bodies is enough flexibility for most situations to get you in the ballpark, or maybe you'll decide that print controls are enough for the kind of shooting you do.

 

[jstraw]

Even using ZS, I'll be damned if I'm going to test *with* every piece of equipment. I test the equipment itself (shutters) and then do my film/development testing with quantified equipment. After that, I use whatever equipment I choose and make adjustments as needed. I carry a laminated table with all the shutter speed adjustments I'm concerned with shown to 1/6 stop.

 

[Roger Hicks]

To quote from a country song that was quite popular in the US some years ago, "what part of no don't you understan?"

What I gave was not a ranking, but a list. For some reason you decided it was a list and have chosen to make it an issue. But I did not give or imply any kind of ranking, and as I have said before, I avoid all discussions about the merits of different formates.

Sandy King

Dear Sandy,

"A shoots a few rolls of 35mm film and makes no money from photography. B shoots hundreds of sheets of LF and LF and makes money from it. C, using MF, is in between."

This is, I think, a fair paraphrase of your post 232. My sole point that this is not a question of extremes: it is a question of two examples. I gave two other examples: the 35mm user who shoots hundreds of rolls a year, and the LF user who shoots a few sheets. We are in full agreement that APUG is a broad church. But the clear implication in your post is that LF users shoot lots of film and make money out of their pictures, while 35mm users don't.

I challenged this partly because it is simply not true, and partly because many people imagine -- incorrectly, as we agree -- that technique can freely be transferred between 35mm, 120 and LF. As LF users such as yourself are usually (though far from invariably) the ones who study the subject most deeply, many people look to them for guidance. Once again, as you yourself freely admit, what works best in LF will not necessarily work best in roll-film or 35mm.

I apologize for upsetting you, as I have clearly done. We started off on the wrong foot with your defence of the assertion that you can measure actual subject brightness ranges with an incident light meter, and I was rather harsh because I thought we had seen off that myth with Don. Thereafter, I admit, I have been reading your posts critically, but once again, I do not think I have been unfair. Had we been on better terms, I should probably have phrased my last comment along the lines of, "Come on, Sandy, those aren't extremes -- they're just examples," and you'd have said, "Of course, sure."

No-one (including myself) denies your knowledge or expertise, but I think we could both benefit from trying to admit our own mistakes, whether of fact or of presentation.

On that last topic, I see that your estimate of cumulative errors in BTZS is somewhat less than mine -- my post 222, your post 250 -- and I would suggest that mine is probably more accurate if they are cumulative, especially taking camera/lens flare into account. Has anyone else any thoughts on this?

Cheers,

Roger

 

[Ole]

... each combination of equipment should be tested in the field, but that would become a very onerous undertaking for people who own many different lenses and/or cameras. ...

That would be me. About nine LF lenses in regular use, with another 15 in backup for those "special needs". One of my "regular" lenses is uncoated, one has "bloom coating", the rest are (with one exception) single coated. Shutter accuracy is all over the place, from "right on" to "opens and closes".

So instead of testing, which would use about as much film as I generally shoot in a whole year, I rely on a combination of knowledge about my equipment, the latitude of the film, and DBI for the trickiest ones. I've found that I get about 80% correct exposures on slide film just by listening to the shutter and adjusting exposure accordingly, so I can't be that far off...

I generally only adjust development in extreme high contrast situations, since I have found that I don't really like the results from "N-" development. I'm working on a way to describe the importance of "mesocontrast", but that's a personal opinion and not really relevant to this discussion.

In 2006 I actually made a little money from photography - three pictures, two from 35mm and one from a MF folder...

 

[Paul Howell]

It is possible to use BTZS or the Zone System or DBI for 35mm (you could carry a few different bodies or swap out rolls for different exposure conditions), but considerations of enlargability with small format are usually more important than nailing the exposure and contrast range on film, so for 35mm it's often better to target negs for grade 3 (thinner negs have less grain) under "N" lighting conditions, and adjust paper contrast as needed for most other conditions.

It would be beneficial to learn one of these approaches, just to see what they can do for you and to understand how to control tonality with exposure and development, and then decide for yourself how to balance the tradeoffs.

You might decide, for instance, that it's a false economy to insist on shooting 36 exposures before changing film, or you might start bulk loading shorter rolls, or you might decide that having two or three 35mm film bodies is enough flexibility for most situations to get you in the ballpark, or maybe you'll decide that print controls are enough for the kind of shooting you do.

I agree, my only addtional thought is when possible, bracket.

 

[Roger Hicks]

I just can't see how the aspects mentioned in the first half of your statement can't be taken from the manufacturer.

Dear Tim,

The manufacturers have a certain sympathy for this stance. Why else would they give ISO speeds and recommended development times?

Cheers,

R.

 

[sanking]

That would be me. About nine LF lenses in regular use, with another 15 in backup for those "special needs". One of my "regular" lenses is uncoated, one has "bloom coating", the rest are (with one exception) single coated. Shutter accuracy is all over the place, from "right on" to "opens and closes".

Ole,

I was actually thinking about you when I wrote the part about some people having a lot of lenses. Not only do you have a ton of lenses, but you have them from all across time, from the old uncoated ones, with and without bloom, to single coated, and I assume you may even have one or two moden multi-coated lenses. To say nothing of the shutters. Testing of all those indiviudal componenets could easily become a full-time job.

Sandy

 

[sanking]

Roger,

Your message has a concilitary tone and I will accept it that way.

It is important, however, that in discussions people be held accountable only for the things they say, not for what others think they may have meant or implied. You write," But the clear implication in your post is that LF users shoot lots of film and make money out of their pictures, while 35mm users don't."

I do not believe a close reading of my original message supports your opinion that my implication was as you suggest. You have made an inference as to my meaning which is not present in the original language, and was not present in my intention.

But there is no need to re-hash what has been said. What has been said is out there and others can read and decide for themselves.

As for the question of total cumulative error, I suggested a maximum of about 1/2 stop based on my own experience and equipment with LF and ULF equipment. All of my LF and ULF lenses are in modern Copal shutters and none of them are off by more than 1/6 of a stop ( at the speeds where I typically use them). WHen I meter a scene I base exposure on a shadow value incident readings, in a part of the scene where texture or detail in my shadows is wanted, so there is really no possibility of significant error in this measument, assuming that the meter is calibrated. So I fully expect that the cumulative errors from hardware to be on the order of less than 1/2 stop.

My assumption is that a person using a modern 35mm rangefinder such as a Leica, with top grade Leitz lenses, should be able to consistently contrrol exposure to an accuracy of 1/2 stop or less.

Lens flare is certainly an important issue, espeically in strongly back lighted situations. I tend to do a lot of work in these kind of conditions and always use a compendium lens hood to minimize problems, but flare can be very unpredictable.

Sandy King

 

[Roger Hicks]

Dear Sandy,

Thank you for your reply. One other point I should like to add, still on a conciliatory note, is that 'ordinary reading' obviously depends on one's background. There are distinct differences between American and English interpretations, for a start.

With modern MC lenses, preferably of relatively simple design (i.e. not complex wide-angles), used in modern, clean LF cameras (or old ones with new bellows), the flare factor closely approaches unity. What I query is how many people use such equipment exclusively. Certes, I have lenses running from the first decade of the 20th century to the early 21st century, and cameras dating back for maybe 100 years, maybe more. I would be surprised if I did not have flare factors with some camera/lens combinations that were easily 2 and coud well exceed 4.

Then with shutters, most are 'lazy' after a few years, and the top speed is notoriously rarely close to the marked speed. Furthermore, leaf shutter efficiency varies widely with aperture.

Like (I suspect) many others, I use lenses at a wide variety of apertures, from full bore with my 21 inch f/7.7 Ross for portraits (and indeed with my f/4.5 Apo Grandagon when I used it for hand-held Polaroid Sepia photography with my MPP) down to f/128 with my 300/9 Nikkor which barely covers 12x15 inch.

There are also the points I made about meter accuracy and the way users read them, in an earlier post.

This leads me to suggest that your 1/2 stop estimate of the likely discrepancies between lab-tested film and 'real' pictures is perhaps too optimistic, based on the assumption that others use equipment similar to yours. I would suggest that for many -- perhaps most -- LF photographers, 1 stop is quite probable and 2 is far from improbable.

I do not deny that experience will allow anyone to 'fudge out' most of these factors via informed guesswork, but of course, this is not the same as measuring it. I note, though, that BTZS takes account of lens flare, and I should be grateful if you (or another BTZS user) could explain how, for the benefit of those who do not use the system.

I look forward your response.

Cheers,

Roger

 

[bogeyes]

It is possible to use BTZS or the Zone System or DBI for 35mm (you could carry a few different bodies or swap out rolls for different exposure conditions), but considerations of enlargability with small format are usually more important than nailing the exposure and contrast range on film, so for 35mm it's often better to target negs for grade 3 (thinner negs have less grain) under "N" lighting conditions, and adjust paper contrast as needed for most other conditions.

It would be beneficial to learn one of these approaches, just to see what they can do for you and to understand how to control tonality with exposure and development, and then decide for yourself how to balance the tradeoffs.

You might decide, for instance, that it's a false economy to insist on shooting 36 exposures before changing film, or you might start bulk loading shorter rolls, or you might decide that having two or three 35mm film bodies is enough flexibility for most situations to get you in the ballpark, or maybe you'll decide that print controls are enough for the kind of shooting you do.

Yes, two roll film bodies both loaded with the same film, one rated/developed for 'normal' scenes, the other rated/dev for high contrast scenes works for me.

 

[sanking]

You might decide, for instance, that it's a false economy to insist on shooting 36 exposures before changing film, or you might start bulk loading shorter rolls,

On the subject of shorter roll, my Fuji GW690III has three counters, one for 16 shots on 220 film, another for 8 shots on 120 film, and another for 4 shots on 120 film.

Has anyone seen this feature on other medium format cameras? I can not figure out the purpose, unless at one point someone produced 120 film in less than standard length.

Sandy King

 

[Roger Hicks]

On the subject of shorter roll, my Fuji GW690III has three counters, one for 16 shots on 220 film, another for 8 shots on 120 film, and another for 4 shots on 120 film.

Has anyone seen this feature on other medium format cameras? I can not figure out the purpose, unless at one point someone produced 120 film in less than standard length.

Sandy King

Dear Sandy,

Yes, they did. I had some once. As far as I am aware it was only ever widely available in Japan (and may still be so), though I think I bought mine in California.

Of course the 'standard' length has changed too. For the first 20 years or so it was 6x 6x9cm, not 8x.

Cheers,

R.

 

[Paul Howell]

On the subject of shorter roll, my Fuji GW690III has three counters, one for 16 shots on 220 film, another for 8 shots on 120 film, and another for 4 shots on 120 film.

Has anyone seen this feature on other medium format cameras? I can not figure out the purpose, unless at one point someone produced 120 film in less than standard length.

Sandy King

The Mamyia University has a back with options for 4.5X6 6X6 and 6X9 or 6X7 I dont recall off the top of head the latter. I have seen a few fixed lens MF with 4.5X6 and 6X7 or 6X6, older folders.

 

[Allen Friday]

I finished reading BTZS today, and an earlier assumption of mine did not pay out. That is, How is the camera, lens and meter taken into account with testing? The Zone System addresses this directly. It looks to me that BTZS is great for paper and film matching, but it doesn't take the hardware into account, other than "testing your materials in the field and fine-tune". An earlier post stated that the ZS takes alot of time because you have to do alot of testing and fine tuning your exposures. How is this any different from what is being necessary for BTZS?

Timbo,

RE: Testing

Your very good question got lost in the recent meanderings of this thread, and I would like to give my response to it. Sandy’s post #250 is right on the mark, and I will not be disagreeing with it. But, I do take a different tack on why I use BTZS for my testing.

The ZS and BTZS both contain two parts: 1. Film and paper testing. 2. Metering system. In my view, neither testing system is 100%. When I come out of the darkroom with my test results, I still have to do “field tests” under ZS or BTZS. After all, the proof of any system is in how real negatives print.

To me, the issue is which system gets me to the end result--making negatives which consistently print on my chosen paper with a minimum of hassle--the fastest, with the least cost and the least effort. Since neither system gets me that directly out of the darkroom, the question then is which system gets me to the field testing stage the fastest. To me that testing system is BTZS.

When I first started experimenting with BTZS, I did a side by side comparison of BTZS and the ZS. I picked a film I have never worked with and tested it on both systems with the same paper. My results at the end of the darkroom tests were very similar on film speed and development times. This was a few years ago, so I don’t remember the exact amount of variation.

Both systems had to be fine tuned in the field. I actually had to go out and shoot negatives and print them. I found that in fine tuning, I was doing the same thing under both systems: I printed at my standard print time and looked at the shadow detail and the highlight detail to evaluate my straight print. Some BTZS practitioners will extol the virtues of BTZS as an “objective” system--which it is until you get to the field test stage, where it acts just like the ZS.

I found that BTZS gets me into the field much faster and efficiently than ZS testing. But, for the initial test, one where you are starting from scratch, the time savings alone was not enough to make me change systems. The real time savings came when I started to play with other papers. I do quite a bit of work on AZO. Grade 2 Azo has a scale of 1.65. Grade 3 Azo has a scale of 1.05. To test these two papers with the ZS, I would have had to do two complete tests (although some of the negatives may have been able to serve double duty.) With BTZS, I could do one film test and two simple paper tests and get results for both papers. Grade 2 and grade 3 Azo have very different looks. I have to decide before exposing the film which paper I want the final print to be on, and then use the appropriate exposure and development for the grade I choose.

Once the film characteristics are identified by the film test, they can easily be applied to different papers. You do a simple paper test, plug it into the computer and out pops a very good starting point for the field test. (As an aside, I generally test more than 5 sheets of film at a time under BTZS. This is because I like to test film for both silver gelatin paper and for alternative processes. The alt. processes tend to have very long scales which may not be covered by the 5 sheet test, so I exposed more sheets and develop for longer to cover both types of paper.)

What I recommend is that you try both (provided you already have a densitometer). See in practice how much, if any, variation there is and decide which system works for you. Also, if I didn’t have the software, I wouldn’t use BTZS. It would drive me crazy to sit and plot paper and film curves. But that’s just me.

Personally, I hate film and paper testing. I do it because it makes me a better photographer. I think it is kind of like an athlete doing sit ups, for almost every sport, you have to do the sit ups. Anything that cuts down on my testing time is of great value to me, as long as the results are there. For me, BTZS gets me the results I need in the most efficient and effective manner.

 

[sanking]

I do not deny that experience will allow anyone to 'fudge out' most of these factors via informed guesswork, but of course, this is not the same as measuring it. I note, though, that BTZS takes account of lens flare, and I should be grateful if you (or another BTZS user) could explain how, for the benefit of those who do not use the system.

I look forward your response.

Cheers,

Roger

Roger,

I hoped someone else would address the flare issue since I do not do the "full Monty" with Davis' system of flare control. However, since no one dropped by I wil briefly explain the system.

Basiclally, you build a flare test box, which is a kind of photographic black hole. Then you place the box in the shadows of the subject area and photograph it with normal exposure. You do this in a variety of scenes with different SBRs. Finally, you read the Black Hole Density and calculate a Flare Density. The Flare Density is then plugged into the Winplotter program.

With N or SBR 7 conditions Flare Density will range from about 0.01-0.02 with modern coated lenses to 0.10 or even higher with old lenses. It is higher in SBR conditions of 8 or more, lower in SBR conditions of 6 or less.

I built the flare box and carried out some of the testing, but somewhere along the line I made a decision to just use a very effective lens hood and plug in the Flare Factor numbers derived by Davis. That is why I wrote that I do not do the full Monty with this testing procedure.

Sandy King

 

[timbo10ca]

Timbo,

RE: Testing

Your very good question got lost in the recent meanderings of this thread, and I would like to give my response to it. Sandy’s post #250 is right on the mark, and I will not be disagreeing with it. But, I do take a different tack on why I use BTZS for my testing.

The ZS and BTZS both contain two parts: 1. Film and paper testing. 2. Metering system. In my view, neither testing system is 100%. When I come out of the darkroom with my test results, I still have to do “field tests” under ZS or BTZS. After all, the proof of any system is in how real negatives print.

To me, the issue is which system gets me to the end result--making negatives which consistently print on my chosen paper with a minimum of hassle--the fastest, with the least cost and the least effort. Since neither system gets me that directly out of the darkroom, the question then is which system gets me to the field testing stage the fastest. To me that testing system is BTZS.

When I first started experimenting with BTZS, I did a side by side comparison of BTZS and the ZS. I picked a film I have never worked with and tested it on both systems with the same paper. My results at the end of the darkroom tests were very similar on film speed and development times. This was a few years ago, so I don’t remember the exact amount of variation.

Both systems had to be fine tuned in the field. I actually had to go out and shoot negatives and print them. I found that in fine tuning, I was doing the same thing under both systems: I printed at my standard print time and looked at the shadow detail and the highlight detail to evaluate my straight print. Some BTZS practitioners will extol the virtues of BTZS as an “objective” system--which it is until you get to the field test stage, where it acts just like the ZS.

I found that BTZS gets me into the field much faster and efficiently than ZS testing. But, for the initial test, one where you are starting from scratch, the time savings alone was not enough to make me change systems. The real time savings came when I started to play with other papers. I do quite a bit of work on AZO. Grade 2 Azo has a scale of 1.65. Grade 3 Azo has a scale of 1.05. To test these two papers with the ZS, I would have had to do two complete tests (although some of the negatives may have been able to serve double duty.) With BTZS, I could do one film test and two simple paper tests and get results for both papers. Grade 2 and grade 3 Azo have very different looks. I have to decide before exposing the film which paper I want the final print to be on, and then use the appropriate exposure and development for the grade I choose.

Once the film characteristics are identified by the film test, they can easily be applied to different papers. You do a simple paper test, plug it into the computer and out pops a very good starting point for the field test. (As an aside, I generally test more than 5 sheets of film at a time under BTZS. This is because I like to test film for both silver gelatin paper and for alternative processes. The alt. processes tend to have very long scales which may not be covered by the 5 sheet test, so I exposed more sheets and develop for longer to cover both types of paper.)

What I recommend is that you try both (provided you already have a densitometer). See in practice how much, if any, variation there is and decide which system works for you. Also, if I didn’t have the software, I wouldn’t use BTZS. It would drive me crazy to sit and plot paper and film curves. But that’s just me.

Personally, I hate film and paper testing. I do it because it makes me a better photographer. I think it is kind of like an athlete doing sit ups, for almost every sport, you have to do the sit ups. Anything that cuts down on my testing time is of great value to me, as long as the results are there. For me, BTZS gets me the results I need in the most efficient and effective manner.

This seems like a very reasonable answer, and appeals to my philosophy on the matter- thank you very much. I notice that the need fo fine tuning in the field tends to get played down a bit when initially looking at these 2 systems. I see that they are more of a "good head start", to get you close. I also appreciate where BTZS can get you there faster.

Your analogy to sit-ups is all to true. I really don't want to do a bunch of testing either- it would occupy more of my time than I already have to use for shooting! I want to get as good a negative as I can however. Like you, I want this as fast as possible. I will give BTZS testing a try, but I don't have any desire to get the software (although the "lite" version came with the book and DVD I bought) and do the analyses myself. I think I'll send the film and paper off and have them read it at the View Camera store. Initially I thought this was the perfect solution for me, until Sandy said that unless you're doing it all yourself with your own densitometer (which I don't have), you won't be able to take it very far. I guess it's a start though (and is better than what I'm presently doing). I realize it will be far from perfect due to the "fine-tuning" exclusions I will be making to try to keep things relatively simple (see below). If I decide to go further with it, I may need to start doing my own testing, whether I want to or not- I'm beginning the quest for that perfect negative. I have an RH Designs ZoneMaster II and a Stopclock Pro, which is supposed to act as a densitometer. Is there any way of using this for BTZS testing? I can see it for film (transmission densitometer), but not for paper- could you use it for reflectance?

I have to admit that the film/developer/paper testing sat fine with me when reading through BTZS. I feel a little overwhelmed however with the "extras" at the end of the book. I felt like it wasn't going to end- testing for flare being a big one. I don't see me constructing that box contraption then re-doing all those curves and graphs. Then there's the compensation for reciprocity (not only film exposure, but also factors to adjust development by). Add in bellows extension, paper flashing, toning.... alot of re-adjustments, and things to take into consideration before you trigger that shutter! Do you have to go back and re-do curves for all those values as well? It seems like alot of add-on stuff to remember. Even a checklist seems bloated- do this, this then this. If this, then go back and re-do curves and then do this this and this.... I'm not even going to *consider* the variations in film and paper development sections!

That Power dial isn't the easiest thing to figure out going by his directions either. He either left out some labelling, or missed some steps (or is assuming that I know the book by rote). What I need is a step-by step tutorial on how to use that thing under different situations. I don't feel I should have to go out and buy a palm pilot just to use this information! Maybe it's on the DVD.

Just out of curiosity- I'm using FP4+ 5x7 in Ilfosol S, printing on Ilford Multigrade IV RC. Does anybody have test data/graphs for these materials for me to try out, and compare to once I get my own materials tested? I also have some Ilford RC Cooltone to try, and was given a bunch of Ilford FB Warmtone. I have this stuff, but am still trying to stick to the one film/developer/paper combo until I have it figured out.

Tim