Film testing

[Roger Hicks]

Then I am going to remove the negative and replace it with a blank piece of film from the same roll and do a test strip to find minimum time for maximum black.

I will then replace the negative and expose for this time. If the negative was exposed and processed correctly, I should have a good print (assuming grade 2 to 3 filtration).

Dear Steve,

I'm not convinced by this, as it assumes zero density (above fb+f) somewhere in the 'real' negative, which can by no means be taken for granted. Even if it could, how much use is it?

Like many people, I prefer generous exposure for three reasons. First, the tonality is often better. Second, I'd rather have detail and throw it away if I don't want to print it, rather than not have it there if I do want it. Third, the tolerance in B+W photography is much greater for over-exposure than for under-exposure, so it makes sense to err on the side of over-exposure if you're going to err at all -- though of course over-exposure means bigger grain and reduced sharpness, so you don't want to go too far.

My own preference is for basing exposure on a shadow reading of the darkest area in which I want texure: about 2-1/3 to 2-2/3 stops less than the reading taken using the true ISO of the film in the developer I am using.

Basing exposures on true ISO speeds and shadow readings saves a lot of tedious and (for most people) unnecessary speed testing, because, after all, shadow readings (toe speed) are what ISO speeds are based on. I normally take the box speed as the true ISO in D76/ID-11, and reckon on +2/3 stops in DD-X or DD-X or Microphen and -2/3 stop in Perceptol. There is seldom any need for greater precision than this.

Please (this isn't directed at you, Steve, but at those who don't actually understand what ISO speeds are) don't tell me that box speeds aren't true ISO. Even with Fomapan 200, they are, though you have to read the spec sheets to see that Foma 200 is only 200 in speed increasing developers, and that only by courtesy; its true ISO in just about everything matches that of FP4 Plus, viz. 80-180 or so.

If you use any metering technique other than shadow readings, such as pissing around with 'mid-tone' grey card readings, or if you grievously curtail development, no-one can predict what personal EI will work best. With through-lens meters on a sunny day, for example, I'll normally set an EI that is 2/3 stop or even 1 stop lower than the true ISO, or 'interpret' the reading according to the subject.

Cheers,

R.

 

[Steve Smith]

Dear Steve,

I'm not convinced by this, as it assumes zero density (above fb+f) somewhere in the 'real' negative, which can by no means be taken for granted. Even if it could, how much use is it?

I'm not sure that I'm convinced either but I'm going to try it anyway!

Like you, I tend to go for plenty of exposure. Reading various articles on finding your 'personal film speed' I see that most of these tests end up with an EI rating around half that of the film's ISO i.e. twice the exposure that you would get with using the ISO setting.

With that in mind, an extra stop of exposure is probably a fairly good rule of thumb whether you have done your personal tests or not.

As for my darkroom experiment, it it just that - an experiment because I am currently in an experimental mood!

It just seems to me that when we meter a scene we can use the ISO or EI and our meter readings to set up the camera with a fairly predictable idea of how the image will appear on the film without having to do the equivalent of a test strip on a piece of film before taking the actual image. But when it comes to the darkroom it is a bit more hit and miss. I think there could be a more logical method. I suppose that's what those enlarger lightmeters I can't afford are for!

Steve.

 

[Michel Hardy-Vallée]

But when it comes to the darkroom it is a bit more hit and miss. I think there could be a more logical method. I suppose that's what those enlarger lightmeters I can't afford are for!

Steve.

I've noticed that when I have film that is properly exposed, I am generally in the same ballpark for printing every frame. Sometimes when I want a quick proof I just print the shots I want at 13s, 8x10, f5.6, and that's enough to give me a sense of whether I like the photo or not.

Your test for minimal time for max black by projection through fb+f is the same thing as what one does with a contact sheet (the "proper proof" in Picker-talk). But that means that overexposed photos will look just like that, overexposed. That's why you need a contact sheet to know first which frames are over/under.

A lot of pissing around in printing goes away with a properly calibrated system and a good technique. For my setup, I make most straight prints with times between 10s and 20s. I learned by heart the f-stop sequence: 8, 10, 12, 14, 17, 20, 24; and I go up or down this scale to nail my straight exposure. After that it's dodge and burn, but that's something you can't exactly predict because you use it creatively.

 

[Roger Hicks]

With that in mind, an extra stop of exposure is probably a fairly good rule of thumb whether you have done your personal tests or not.

Dear Steve,

Probably so, but I can't help feeling than an awful lot of it is down to poor metering technique, i.e. not using a spot meter to read the shadows, which is the ONLY way to ensure adequate shadow exposure and no more. People who refuse to meter this way (usually on the grounds of convenience -- I do not exempt myself) have to build in 'fudge factors' which, as you say, are typically around one stop. With a spot meter, you can afford to be quite a bit closer to the ISO speed.

Cheers,

R.

 

[Daniel_OB]

Timbo10CA
Many want your way to use zone system with 35 mm and just gave up saying it does not works with 35mm.
It works in just any format. But take care.

What film area is smaller the more accurate you have to be for the same result. Spot meter (around 1 deg) will be a great helper. So learn with time and concetrate on accuray (exposure, developer temperature, developing time, film speed,...).
Go Canada Go.

www.Leica-R.com

 

[timbo10ca]

Tim, the first thing to understand about film testing is that nothing is linear. Development effects densities unequally. You're always doubling or halving the quantity of light. There is a discrete step between unexposed film and minimal exposure, not a continuous one, etc.

If you increase exposure and reduce development, that's not doing the same thing as reducing exposure and increasing development. The reason lies in the fact that development impacts highlights in a different way than it impacts the shadows.

The nature of the reaction of photosensitive emulsions (film and paper) to light is the single most fundamental thing to grasp. It's because of its characteristics that what seems to be equivalent operations are not. You should probably get some graphics of a characteristic curve to help you.

At this point, I guess if you want to know the WHY rather than the HOW, you need to get a textbook like Ansel Adam's The Negative (the last editions are way more readable than the earlier ones).

The reason why the EI is different between the N, N+ and N- is twofold: first, because development also effects slightly film speed, as I've said in an earlier post. But that's just a minor correction, sometimes half to a third of a stop. The real reason is because that's how you control the contrast.

Let's say you have a scene. A portrait in the sun, light diffused from a lightly overcast sky. The light comes from the left side of your subject. Her left side is brighter than her right side because of this. You meter her left side and her right side. There's a difference of one stop. If you expose and develop your film normally, there will be a difference of one stop on the final print. You have exposed and processed for N, and thus you did not alter the contrast of the scene.

Let's say you expose it less than in the previous case. What it does is that overall, the photo will be darker, right? You have slightly underexposed. Both sides will be darker, but will bear the same relationship to each other: one stop of difference.

But let's say that on top of that you develop more. THAT's where the magic begins. The darker side will stay dark, but the brighter side will be three stops brighter than the darker side on the negative, and on the print you will also see this difference. You will have a portrait with more contrast. You have exposed and developed for N+, and you have augmented the contrast of the scene.

There is alot of great info in this discussion. Michel, I guess what I was trying to get at (and I have read all 3 of AA's books, and have a relatively good understanding of film curves), is that in The Negative, all the talk of film testing is directed at getting a single EI, or personal ISO for your camera/film/developer system, and sticking with it regardless of lighting condition, then applying the tenets of the Zone System to it. It never mentions anything about choosing an ISO for different lighting conditions, and then developing accordingly, which I think is subjective (Light cloudy, medium cloudy.... what the hell is that anyway?!). The way I understood the Zone System is by measuring the exposure range, and keeping the shadows on Zone 3 (using your single pre-determined ISO), you then expand or contract the scene if necessary using your development. Is this just the same as using box speed for cloudy/dark, NOT metering and placing shadows on Zone 3 (just knowing through experience that they'll be there using that film speed), then increasing the development to get a full range in tones? My confusion is laying in that I've been thinking that you use these different film speed ratings depending on lighting, and still placing shadows on Zone 3, as there are an infinite number of film speeds you could choose depending on the lighting in the scene, and the Zone System is supposed to be a standardization to remove this. (Am I daft and just carrying on a circular discussion?)

Tim

 

[Michel Hardy-Vallée]

It never mentions anything about choosing an ISO for different lighting conditions, and then developing accordingly, which I think is subjective (Light cloudy, medium cloudy.... what the hell is that anyway?!). The way I understood the Zone System is by measuring the exposure range, and keeping the shadows on Zone 3 (using your single pre-determined ISO), you then expand or contract the scene if necessary using your development.

I checked back in my AA book, and indeed he sticks to one EI for all development times. The reason why my EI shifts between dev times is because film speed varies a bit with development time. So I was a bit overboard in the way I explained it, and yes, you can use a fixed EI for all your dev times, but while the effect of development is mostly felt in the highlights, it can effect the shadows as well, although only to a lesser extent. You may or may not need to compensate for EI, and I think that is also dependent on the type of film developer you use. If it's simpler for you to stick with one EI, go for it.

If you go with the fixed-EI procedure, you would have, say an EI of 200, N=6; N- = 4; N+ = 8. If you do further testing, you might find that you need to change your EI for N- to 160, one-third of a stop more exposure, and to 250 (one third less) for N+ to keep the exact same density in the shadows. But as I said, that should be a minor correction, and my previous example was a bit exaggerated.

The only non-subjective way to assess the contrast of a scene is to use a spot meter and measure shadows ans highlights. Otherwise, one can make an educated guess, but only based on experience. It's an acquired skill, in a seat-of-the-pants way, but it can be good enough for 35mm.

In sum, for the EI-correction method: for a high-contrast scene, you set you meter to 160, measure shadows and place them on Zone III, and develop for 4 mins. For a low-contrast scene, you set your meter to 250, measure the shadows and place them on Zone III, and develop for 8 mins. Nearly all of the expansion/contraction appears in the highlights, and a slight EI compensation is taking care of the slight increased or reduced film speed due to development.

People who use BTZS always calculate precisely the EI compensation, but for many practical purposes it can be ignored.

 

[Donald Miller]

There is alot of great info in this discussion. Michel, I guess what I was trying to get at (and I have read all 3 of AA's books, and have a relatively good understanding of film curves), is that in The Negative, all the talk of film testing is directed at getting a single EI, or personal ISO for your camera/film/developer system, and sticking with it regardless of lighting condition, then applying the tenets of the Zone System to it. It never mentions anything about choosing an ISO for different lighting conditions, and then developing accordingly, which I think is subjective (Light cloudy, medium cloudy.... what the hell is that anyway?!). The way I understood the Zone System is by measuring the exposure range, and keeping the shadows on Zone 3 (using your single pre-determined ISO), you then expand or contract the scene if necessary using your development. Is this just the same as using box speed for cloudy/dark, NOT metering and placing shadows on Zone 3 (just knowing through experience that they'll be there using that film speed), then increasing the development to get a full range in tones? My confusion is laying in that I've been thinking that you use these different film speed ratings depending on lighting, and still placing shadows on Zone 3, as there are an infinite number of film speeds you could choose depending on the lighting in the scene, and the Zone System is supposed to be a standardization to remove this. (Am I daft and just carrying on a circular discussion?)

Tim

Tim, It appears that you are trying to reconcile the irreconcilable.

The Zone System as it is presented in the books that you mention has several areas that are difficult if not impossible to reconcile with reality especially when it comes to tonal representation in the print.

This is especially true when one recognizes that film response is not linear. Paper response is not linear either. For instance one can have what you call a zone III density on a film having a long toe that could be further compromised by a paper with a distinct shoulder which would further alter the tonal representation as it appears in the print.

Zone III is a nebulous if not poorly defined quantity. One person's Zone III might be another person's Zone III 1/2 or even another person's Zone II 1/2.

The most reasonable approach is to adapt the film negative with it's inherent characteristics to the spectral response of the print material with it's inherent characteristics. That however is not covered in the books that you mention...but that is another place where the objective reality is not reconciled with the methodology that you address.

 

[Donald Miller]

The only non-subjective way to assess the contrast of a scene is to use a spot meter and measure shadows ans highlights. Otherwise, one can make an educated guess, but only based on experience. It's an acquired skill, in a seat-of-the-pants way, but it can be good enough for 35mm.

I don't know that I agree that the only non subjective way is to use a spot meter...incident metering (determining the SBR of the scene) seems to be highly accurate in an objective way.

I do agree that EI is a movable (indefinite) factor dependant on the development of the negative.

 

[Michel Hardy-Vallée]

I don't know that I agree that the only non subjective way is to use a spot meter...incident metering (determining the SBR of the scene) seems to be highly accurate in an objective way.

I do agree that EI is a movable (indefinite) factor dependant on the development of the negative.

Well, I just meant that using a light meter to record the intensity of light in precisely defined areas was the only objective way to measure contrast of a scene. I don't really understand how BTZS uses incident light, but I gather that the point remains the same: measure the ratio of light between shadows and highlights.

 

[Roger Hicks]

I don't know that I agree that the only non subjective way is to use a spot meter...incident metering (determining the SBR of the scene) seems to be highly accurate in an objective way.

I do agree that EI is a movable (indefinite) factor dependant on the development of the negative.

Dear Don,

Hold on a minute. How on earth can an an incident meter reading tell you ANYTHING at all about brightness range? That meter could be in front of a square of black velvet on white snow (brightness range close to 6 stops) or the velvet on irs own (brightness range 0 stops) or the snow on its own (brightness range 0 stops again) -- or anything in between.

It is self-evident that the only way you can measure a brightness range is, um, well, to measure the brightness range, i.e. the brightest part and the darkest, and the only way to do that (unless said areas are very large) is with a spot meter. An incident light meter cannot determine subject brightness. Either I'm missing something very obvious -- which is entirely possible -- or you are.

Also, ISOs vary surprisingly little with development, because of the ingenious way the ISO standard is defined (see Stephen Benskin's superb analysis of the Delta X criterion). Under the old Kodak/ASA standard they varied even less because it was openly a fractional gradient criterion, not a fixed density criterion. Of course AA wrote his original books with the fractional gradient criterion in mind, and arguably, if you use his testing methodology, you'll get pretty close to it anyway.

Cheers,

R.

 

[Donald Miller]

Roger,

An incident meter is very capable of measuring the brightness range of a subject or scene because it measures the light falling or registering on the dome and this corresponds to what you are metering. In fact an incident meter can be equally as effective as a spot meter. If one measures the EV of a shadow region and of the highlight region and subtracts the low reading from the high reading then adding this to five you will have the SBR of the scene. By what you wrote, I wonder if you understand the principle of incident metering. I have used the Pentax digital spotmeter
for years. I discarded it after I found that incident metering gave me greater accuracy and now use a Sekonic 558 exclusively.

For your information, a dark card on white snow would be a SBR 5...unless, of course the card was shaded or if the card was lit while the snow was shaded. If this is difficult to comprehend, you might avail yourself of Phil Davis latest book on the subject.

I found this difficult to comprehend at one time...the sensitometric principles in the Davis' book are much more accurate than anything that Adams wrote. My prints using both systems bear this out.

Furthermore, taking Efke PL 100 as an example. The EI of the film at SBR 7 (normal luminance scale) is 50. While at SBR 6the EI is 80 and at SBR 5 it is 100. This is based upon my tests using Pyrocat HD as the developer (1-1-100 dilution). Thus the film that I use can vary one stop in EI by altering development for SBR 2 variance. Tri X and Tmax 100 both exhibit similar characteristics.

Good luck to you.



Don,

Hold on a minute. How on earth can an an incident meter reading tell you ANYTHING at all about brightness range? That meter could be in front of a square of black velvet on white snow (brightness range close to 6 stops) or the velvet on irs own (brightness range 0 stops) or the snow on its own (brightness range 0 stops again) -- or anything in between.

It is self-evident that the only way you can measure a brightness range is, um, well, to measure the brightness range, i.e. the brightest part and the darkest, and the only way to do that (unless said areas are very large) is with a spot meter. An incident light meter cannot determine subject brightness. Either I'm missing something very obvious -- which is entirely possible -- or you are.

Also, ISOs vary surprisingly little with development, because of the ingenious way the ISO standard is defined (see Stephen Benskin's superb analysis of the Delta X criterion). Under the old Kodak/ASA standard they varied even less because it was openly a fractional gradient criterion, not a fixed density criterion. Of course AA wrote his original books with the fractional gradient criterion in mind, and arguably, if you use his testing methodology, you'll get pretty close to it anyway.

Cheers,

R.[/QUOTE]

 

[Paul Howell]

Although I dont fully understand BTZS, but based on the quailty of the work from BTZS practiticners I have now taken my foot of my mouth and admitt that BTZS can produce very remarkable and consitant work.

I do understand the ZS, while in college in the 60s I spent 2 week taking a work shop from Minor White, but as a former working PJ I feel that neither the ZS or BTZS work when shoot fast moving events with a 35mm.

Testing film speed with a 35mm for personal speed is as much about the shutter and internal light meter acuracy as it about the film and developer combo. I now have a SA 7 and 9, meters are stop apart.

For 35mm, when in doubt overexpose by a stop, bracket when possible, 1 1/2 stops over and under, when pushing expose for the highlight and let the shawdows faill where they may.

And how you meter distant shadows with a incident meter?

 

[Allen Friday]

There is alot of great info in this discussion. Michel, I guess what I was trying to get at (and I have read all 3 of AA's books, and have a relatively good understanding of film curves), is that in The Negative, all the talk of film testing is directed at getting a single EI, or personal ISO for your camera/film/developer system, and sticking with it regardless of lighting condition, then applying the tenets of the Zone System to it. It never mentions anything about choosing an ISO for different lighting conditions, and then developing accordingly, which I think is subjective (Light cloudy, medium cloudy.... what the hell is that anyway?!).
Tim

From Ansel Adams, The Negative, 1981, pp. 78-79:

"In practice it will be found that while development modification has its primary effect in the high values, it does also cause some slight density change in the shadow areas. With contractions, the decreased development time causes a slight loss of density (and contrast) in the low values, and a small additional exposure should be given to compensate. For most films and developers, a 1/3 to 1/2 stop increase should be sufficient, unless testing indicates otherwise. Similarly, with expanded development, it is possible to reduce the exposure slightly since the low densities are somewhat strengthened by the increased development time.*

*Some texts refer to this phenomenon as a change in effective film speed. I think it is less confusing to the student to consider the film speed fixed, once determined by testing, and to apply these adjustments separately, just as one does when applying a filter factor. The effect is the same in either case."

So, Adams does address changing the exposure of the film when you are giving it increased and decreased development. He, however, does it as an adjustment to the indicated exposure on the meter, rather than putting a different film speed into the meter and then using the meter reading. But, as he states, "The effect is the same in either case."

 

[Michel Hardy-Vallée]

So, Adams does address changing the exposure of the film when you are giving it increased and decreased development. He, however, does it as an adjustment to the indicated exposure on the meter, rather than putting a different film speed into the meter and then using the meter reading. But, as he states, "The effect is the same in either case."

Ah! You're a keener reader than I am, I thought he stuck to the same EI.

 

[Michel Hardy-Vallée]

Roger,

An incident meter is very capable of measuring the brightness range of a subject or scene because it measures the light falling or registering on the dome and this corresponds to what you are metering. In fact an incident meter can be equally as effective as a spot meter. If one measures the EV of a shadow region and of the highlight region and subtracts the low reading from the high reading then adding this to five you will have the SBR of the scene. By what you wrote, I wonder if you understand the principle of incident metering. I have used the Pentax digital spotmeter
for years. I discarded it after I found that incident metering gave me greater accuracy and now use a Sekonic 558 exclusively.

I still don't understand how you position your meter in relationship to your subject. Let's say you are sixty yards from a barn, looking at it from one of its corner. The sun is setting, at your right. The right hand side of the barn is light. The left hand side is dark. There's a river with piranhas between you and it. You have to meter the contrast range of the scene, between the light and the dark side of the barn. How do you do that?

 

[timbo10ca]

I checked back in my AA book, and indeed he sticks to one EI for all development times. The reason why my EI shifts between dev times is because film speed varies a bit with development time. So I was a bit overboard in the way I explained it, and yes, you can use a fixed EI for all your dev times, but while the effect of development is mostly felt in the highlights, it can effect the shadows as well, although only to a lesser extent. You may or may not need to compensate for EI, and I think that is also dependent on the type of film developer you use. If it's simpler for you to stick with one EI, go for it.

If you go with the fixed-EI procedure, you would have, say an EI of 200, N=6; N- = 4; N+ = 8. If you do further testing, you might find that you need to change your EI for N- to 160, one-third of a stop more exposure, and to 250 (one third less) for N+ to keep the exact same density in the shadows. But as I said, that should be a minor correction, and my previous example was a bit exaggerated.

The only non-subjective way to assess the contrast of a scene is to use a spot meter and measure shadows ans highlights. Otherwise, one can make an educated guess, but only based on experience. It's an acquired skill, in a seat-of-the-pants way, but it can be good enough for 35mm.

In sum, for the EI-correction method: for a high-contrast scene, you set you meter to 160, measure shadows and place them on Zone III, and develop for 4 mins. For a low-contrast scene, you set your meter to 250, measure the shadows and place them on Zone III, and develop for 8 mins. Nearly all of the expansion/contraction appears in the highlights, and a slight EI compensation is taking care of the slight increased or reduced film speed due to development.

People who use BTZS always calculate precisely the EI compensation, but for many practical purposes it can be ignored.

This makes perfect sense- and as Allen pointed out, AA did mention the need to "add a bit" etc as necessary, (but he still sticks with one film speed). I tend to apply this afterward like a filter factor, because it is easier for me. I guess I just prefer to add my subjective wiggle room at the end, where it will hopefully make less of a problematic impact. My degree of experience needs to keep the minimum number of variables, being one film speed, the develpoment times, filter factors and the wiggle room of 1/3 or so stop last depending on if you have to expand or contract your development (the last being left out completely in a "normal" scene, which is where I need to start, to get a standard system of process in place). In time I hope that these all become inherent, but right now, I have to go through a mental checklist. I think I've inherently understood what everybody has been saying throughout this discussion, but am not familiar enough with the subject matter to recognize an "apple" as "le pomme", so to speak. I think I had missed a couple of your mental jumps, but now see what you are saying.

Tim

 

[Allen Friday]

The light falling on you is the same as is falling on the barn. You take a meter reading in the sun and then a second in your own shadow. Compare the two and then add in the BTZS factor and you have your SBR.

 

[timbo10ca]

Tim, It appears that you are trying to reconcile the irreconcilable.

The Zone System as it is presented in the books that you mention has several areas that are difficult if not impossible to reconcile with reality especially when it comes to tonal representation in the print.

Then why does everybody harp on reading these 3 books and doing film testing? I have to take advice and what I read at face value- I don't know any better. I have John P Schafer's books as well, but haven't gotten to them yet. Maybe they will help. I'm reading BTZS now- maybe that will help (although I almost threw it in the trash when trying to wade through the terrible explanations of logs, etc- they made much more sense in highschool). I'll get Fred Picker's book- maybe that will help. See the problem here? Too much reading and no "doing". I just want to get this figured out so that I'm not weighed down when I start using my view camera. LF photography has enough of its own difficulties- I don't want to be guessing about my film and developer as well.

I appreciate all the advice I am getting- you have no idea how much, as I have nobody to teach me. But sometimes the advice is difficult to put into practice, because it is beyond current skills and understanding. When somebody has alot of knowledge and experience in a field, what may seem a simple flippant suggestion can be tough to put into practice by the novice, because they have not reached that stage yet. I have really benefitted from this discourse though. It has clarified many things for me, and solidified them in my mind a bit stronger.

Thanks,
Tim

 

[Michel Hardy-Vallée]

The light falling on you is the same as is falling on the barn. You take a meter reading in the sun and then a second in your own shadow. Compare the two and then add in the BTZS factor and you have your SBR.

Clever. But what if the shadow area is under foliage, so that "through the checkerwork of leaves the sun flung spangles, dancing coins" ?

 

[Donald Miller]

I still don't understand how you position your meter in relationship to your subject. Let's say you are sixty yards from a barn, looking at it from one of its corner. The sun is setting, at your right. The right hand side of the barn is light. The left hand side is dark. There's a river with piranhas between you and it. You have to meter the contrast range of the scene, between the light and the dark side of the barn. How do you do that?

Since the same sun shines on both my camera position as the barn, a incident meter will read the same luminance and shade from the camera position as it will at the subject location.

The only exception to this would be in the case where cloud would affect the light at either the subject postion or the camera position only.

Positioning the dome of the incident meter toward the camera while lit and shaded will give accurate readings.

 

[Donald Miller]

Clever. But what if the shadow area is under foliage, so that "through the checkerwork of leaves the sun flung spangles, dancing coins" ?

Or what if a cow took a dump in the trees and the meter did not capture the crap as it fell?

 

[Donald Miller]

Then why does everybody harp on reading these 3 books and doing film testing? I have to take advice and what I read at face value- I don't know any better. I have John P Schafer's books as well, but haven't gotten to them yet. Maybe they will help. I'm reading BTZS now- maybe that will help (although I almost threw it in the trash when trying to wade through the terrible explanations of logs, etc- they made much more sense in highschool). I'll get Fred Picker's book- maybe that will help. See the problem here? Too much reading and no "doing". I just want to get this figured out so that I'm not weighed down when I start using my view camera. LF photography has enough of its own difficulties- I don't want to be guessing about my film and developer as well.

I appreciate all the advice I am getting- you have no idea how much, as I have nobody to teach me. But sometimes the advice is difficult to put into practice, because it is beyond current skills and understanding. When somebody has alot of knowledge and experience in a field, what may seem a simple flippant suggestion can be tough to put into practice by the novice, because they have not reached that stage yet. I have really benefitted from this discourse though. It has clarified many things for me, and solidified them in my mind a bit stronger.

Thanks,
Tim

Tim, I can't speak for anyone else and what they recommend. I observe a fair amount of parroting taking place in the area of recommended procedures. I understand what you are saying about complexity of the process...it can be a bit much at times.

Looking at this logically, since we are engaged in making prints rather than negatives as the final product, doesn't it make sense that we would be starting with determining the characteristics of the print material and then tailoring the camera negative to fit the paper rather than assessing some arbitrary value sofar as density or exposure point to the negative.

Think about it this way if you will...why would someone arrive at a film exposure that evidences a .10 density above FB+fog and then effectively reduce that EI by two more stops (Zone III exposure)? If the film needs two stops more exposure (Zone III exposure again) than the first value wouild seem to be inadequate in practice. Perhaps you can come up with a reason for doing this...I can't come up with a good reason...the exposure at the determined EI at that EI is either adequate or it is not.

I really don't care what someone else does so long as they are happy with their results. I have found BTZS produces better prints or I would not be using it.

 

[Michel Hardy-Vallée]

Or what if a cow took a dump in the trees and the meter did not capture the crap as it fell?

For instance. That would be a terrible loss to have it underexposed. Crap is essential to art!

 

[MattKing]

I am not sure whether I understand this correctly.

I take from these discussions about BTZS that the exposure and development recommendation that results from use of the BTZS system does vary with the light hitting the subject, but does not vary with the reflectance of the subject.

If my understanding of the Zone System is correct, the exposure and development recommendation that results from use of the Zone system does vary with the light hitting the subject, but also varies with the reflectance of the subject.

Am I totally confused?:confused:

Matt