Zone I develop question

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Willie Jan

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Hi,

i started to develop fuji across 100 to find the best time for my system.
So a test with zone I to start with.
I already had a roll of film with the gray card & the kodak step wedge taken, i shot zone V and zone I behind each other for the whole roll. The film was rated 64 asa (i know this is wrong).

What i did is develop parts of this across film in:

rodinal 1+100 14min I=0,04 V=0,52
rodinal 1+75 14 min I=0,04 V=0,76
rodinal 1+50 10 min I=0,05 V=0,78
Pyrocat HD 1:1 14min I=0,07 V=0,88
Pyrocat HD 2:2 10min I=0,08 V=0,93
D76 1+3 11 min I=0,04 V=0,62

The development was always first minute agitate continuously, after that once a minute.

I espected that the decrease in developer dilution would increase the EI. But my results do not show this.. Besides that different developers such as d76 would need to boost the EI, but this also is not the case...

Questions:
1) Is it right to say that decreasing the dilution does not effect the Zone I

2) Could an increase in agitation help the zone I?

3) I overexposed the zone I by 2/3 stop, would an increase of 1/3 to 1 stop
(expose as 50) make such a different?

My goal is not to get the right times right away but i want to understand what happens.

Regards and thanks for your help.
 

j-fr

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I would suggest a rather different approach. Looking for zone I is like going blindfolded into a dark room to look for a black cat - that isn't there. It is just one of many misunderstandings in the zone system that zone I does not change when you change developing time.

Instead you should start by focusing on zone V. A good negative density for zone V would be something close to 0.70. So you make three exposures of your grey card (you can use a piece of white paper as well, just expose according to the exposure meter reading). For your first test, use the ISO speed of the film. First exposure directly as read from the meter. Second exposure minus 3 steps (zone II). Third exposure plus three steps (zone VIII). Develop the test and measure the first negative. If the developing is correct, the density should read something rather close to 0.70. When using the ISO speed of the film and Rodinal, I would expect the zone II to be 0.10 - 0.15, which is not enough. My guess would be that the zone VIII (+3) negative will read something around 1.40, maybe even higher. And that's is too much.

If you make at test using an EI of 50 instead of the ISO speed of 100, you could get values like this:

- 3 (zone II): 0.15 - 0.20 (maybe even as high as 0.25)
Zone V: close to .70
+ 3 (zone VIII): 1.25 - 1.35

If you can get values like these, you have a very good exposure and developing for a normal contrast, and you can make negatives that are easy to print.

Changing EI from 100 to 50 will result in a perceptible change in contrast. A change from 64 to 50 can only be read on the densitometer, but will hardly be visible in practical work. For a beginig, go for the clear and visible differences, first of all: get a good "normal contrast", and do not go hunting for small and insignificant differences.

As for you questions:

Decreasing dilution does not affect the low values, but - contrary to common superstition - gives higher highlight values.

Agitation does not affect zone I. All you can do to raise the lower zones, is raising exposure. Or use one of the very few developers that can raise the lower zones, most notable the Tetenal Ultrafin. (D-76 does not boost the EI, as you expect it to. With D-76 the "normal contrast will mostly be found at EIs somewhere between the ISO speed and half the ISO speed.)

It is impossible to judge an increase of exposure of one third of a step from zone I. Zone I is a ghost, and small changes in this zone are of minor importance.

If you want to stick to the zone system, go to White-Zakia-Lorenz: "The New Zone System Manual", and take a look at their "Alternative Planning Routines". They have something there called "Bi-directional Contrast Contrast-Control" with zone V as the starting point, not zone I. It is, in my opinion, the only way to make sense of the zone system. (My copy of the book is from 1985, so it may be hard to find today)

Good luck!

j-fr

www.j-fr.dk
 
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Willie Jan

Willie Jan

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with the -3, +3 test you mean why bother about the zone i, because it will not show up on your print eventually...

So test about the two possible edges of the paper (6 stops).

Why is half the world than telling to get zone I right ????
is that some old film solution, no longer usable for new film types?

Willie Jan
 

juan

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I don't think they are telling you to get Zone I right. They are trying to tell you to find out the minimum time to print through film base and fog.

Take an unexposed negative (or frame on roll film) and develop it for whatever the normal time is, fix it, wash it and dry it. Then make a test print - put the negative in the enlarger (or in the contact print frame if you contact print), and make a test strip. I usually use 2-second intervals. Mark the height on your enlarger, and note the f stop you use (should probably use f8 or f11).

Develop, fix, wash and dry your test print. Then look for the first strip that is maximum black. Don't be obsessive about what black is - just the first strip that is really dark. Note the time it took you to print that strip. That's your Standard Negative Printing Time (Minor White) or Proper Proof Time (Fred Picker.)

You then make Zone VIII test negates, print them at the standard time you have arrived at, being sure to set the enlarger at the same height and the same f-stop. The negative that is a little darker than the white paper base is a proper Zone VIII. Adjust development of your negatives as needed to achieve this.

By using this method, you have determined the maximum black your paper is capable of achieving, and have determined how long to develop your negatives to achieve a proper Zone VIII on that paper.

Or, buy one of Bruce's test kits. They're only $12.
juan
 

mmcclellan

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Zone I is .1 density over filmbase+fog (fb+f). What is the density of unexposed film? Dilution and times have little effect on Zone I density; this test is about setting your exposure index (EI). Once you get that nailed down, do a development test for Zone VIII using the EI you have determined. Once you've got those two numbers down, you're good to go!
 

noseoil

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Willie, this thread will most likely open a large can of worms, complete with flame wars, name calling and nomex underwear. Let's see how long it takes (another experiment)?

All zones are important in a print. In order to have sparklind highlights, there must be enough contrast to set them off by showing dark values as well. The system I've started using deals first with the paper, then with the film (BTZS). It uses the paper's range of values to test the film's contrast, because what is a correct development for one paper is not necessarily correct for another. What is important is the range of values in a print, and being able to predict and control where these values occur in a shot at the time of exposure and development, which gives the correct values in a print.

Zone one is important because it is the bottom of the print, or your exposure value (you could also argue that zone 0 is important, or zone 2). The relationship between zone 1 and zone 7 (or 8) is also important, but if you have a system which allows you to get all of it at one time, you have something which works. If the paper can "see" 5 stops, what good is a film which sees 10 stops? 10 stops on the film is useless to the paper. 5 stops on the film is what we want to see here, so it is the relationship between exposure, development and print which we want to see when all of the words are farted and the smell is long gone. It is just getting the balance between film and paper we wish to achieve. Use whatever works for you to understand what is there. I use zone 3-7 for what I do in most cases (what the eyes can see on the paper), but this can change when I want something different. You have to start somewhere, so exposure for shadows is a good place to begin. Film speed can vary with dilution and development time, just not as much as highlight values do. tim
 

Roger Hicks

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A lot also depends on how many Zones you believe in: the original symmetrical 9-Zone system, the intermediate asymmetric 10-Zone or the later symmetrical 11-Zone where (as I recall) even Saint Ansel reckoned you couldn't always differentiate the extreme Zones.

Paper gives a brightness range of a bit over 7 stops -- it varies from paper to paper -- but it can produce this range (from maximum black to paper-base white) in response to a projected image log brightness range of anything from about 0.45 (grade 5 graded) to 1.6 or more (grade 00). That's after allowing for enlarger flare...

The actual densities on the negative, especially the minimum density, are less important than the density range: the minimum printable density is about 0,03, but 0,10 is taken because it's the ISO standard speed point and gives results surprisingly close to the old fractional gradient system when used at the ISO standard contrast.

The only way to be 100% sure of adequate shadow density is to meter the shadows (or darkest areas) in which you want texture, and key the exposure to that. This is the basis of negative film speed. No system of film speed rating is based on mid-tones, nor can it be, because the mid-tone may be in the middle of a brightness range of, for example, 4:1 (mist) or 1,000,000:1 (a sunny day with the sun in shot)

The optimum exposure and development will depend on the subject brightness range, the shape of the characteristic curve of the film (and the paper you plan to print it on) and the ISO(R) of the paper you plan to print on -- and also on personal personal preference: plenty of photographers get exquisite results with techniques which are hard to defend on technical, theoretical grounds.

There are essentially two schools of thought, both defensible. One is that the Zone System reduces sensitometry to a series of simple if time-consuming tests, allowing optimization of personal EIs and development times. The other -- to which I adhere -- is that if you understand a reasonable amount about basic sensitometric theory, the Zone System overcomplicates some fairly simple concepts that could better be explored by taking real pictures and making iterative changes to exposure and development until you get the prints you want, which should take fewer films than fiddling about with grey cards.

Either way, both Zone System users and those who eschew the System will agree that if you are going to err, then err on the side of over-exposure, i.e. rate the film at less than its ISO speed. How much less will depend om a wild range of variables but 1/3 to 2/3 stops is normal and anything much over 1 stop should, unless you are using a speed-reducing developer, lead you to re-examine your overall process.

There is a whole free module on not using the Zone System in the Photo School at www.rogerandfrances.com, but there's one thing worth repeating here. If it works for you, great: use it without hesitatiom. If it doesn't work for you, don't think of it as a personal failing. At least as many great photographers have worked without the Zone System as have worked with it. I do not count myself as great, but equally (having tried it some decades ago) I am 100% sure that the Zone System hinders my photography more than it helps. It is very much a personal choice.

Other free modules that may be of interest include ISO film speeds and subject brightness ranges.

Cheers,

Roger
 

j-fr

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Willie Jan said:
with the -3, +3 test you mean why bother about the zone i, because it will not show up on your print eventually...

No, zone I will show up in a fine print, but it is impossible to determine by printing test negatives, using the basic exposure time for the paper, as the classic zone system description does.

So test about the two possible edges of the paper (6 stops).

Yes, and test for something that comes out in visible and meaningful differences and not number that can only be read on a densitometer.

Why is half the world than telling to get zone I right ????
is that some old film solution, no longer usable for new film types?

Zone I is probably a leftover from the ASA(now ISO) film standard. It is, as an industrial standard, very useful to prevent the manufactureres from claiming unrealistic high film speeds, but beside that it is of little practical value.

Willie Jan

j-fr

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j-fr

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BBarlow690 said:
No densitometer required, and you work with Zone I (the low end of your materials - tuning the basses of the orchestra) and Zone VIII (the high end - tuning the piccolos). If you get both ends right, the middle takes care of itself. If you try to tune the violas, the ends can still be flat or sharp. This way matches the materials to each other, making full use of each.


Bruce Barlow
www.circleofthesunproductions.com

Wrong! If you have both ends right, the middle is probably out for lunch. That is because most film curves are not straight, but upswept, concave. Some more than others. So the most common problem is, that when boths ends are correct, the middle is too low. With some films and developers even much too low. And there is no paper with a downswept or convex curve to help.

j-fr

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mmcclellan

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Doing the Zone I test is pretty critical, whether you're using "old style" emulsions or newer ones. If you don't get the film speed right, you will have empty shadows in your paper. I've looked at a lot of student work over the years and if you're dodging a lot of shadows and burning a lot of highlights, then you've got problems with your Zone I and VIII densities, all of which can be easily avoided with a few hours of testing on a Saturday afternoon. Use three hours now to save ten minutes later, in other words.

I have yet to test a film that shows the rated ASA to work. It's almost always half -- that, at least, is my experience. What to do? Find out for yourself! If you nail down your effective film speed, get a good development time that delivers on the highlights, you'll have good negatives consistently that require a minimum of dodging and burning and your confidence level in your materials will soar.

Rather than listen to a lot of opinions, test and see for yourself. That way you will reach your own conclusions and know for sure. :smile:
 
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Willie Jan

Willie Jan

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would it than be a better test to shoot a gray card with a kodak step wedge, develop, find the time where the gray is 0.70, and make a print of it so that the print is exactly 0.70 at gradation II. When so the kodak curve should be from white to deep black.

Conclusions after print is made:
If the white is not white, the density of the neg is not high enough (longer development)
If the white is to white over more steps, the density of the neg is to high, (shorten the development)

if the black is not black, the density of the neg is not low enough (higher EI).
if the black is to black over more steps, the density of the neg is to low (lowe EI)
 
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j-fr

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Willie Jan said:
would it than be a better test to shoot a gray card with a kodak step wedge, develop, find the time where the gray is 0.70, and make a print of it so that the print is exactly 0.70 at gradation II. When so the kodak curve should be from white to deep black.

Conclusions after print is made:
If the white is not white, the density of the neg is not high enough (longer development)
If the white is to white over more steps, the density of the neg is to high, (shorten the development)

if the black is not black, the density of the neg is not low enough (higher EI).
if the black is to black over more steps, the density of the neg is to low (lowe EI)

I'm not sure what you mean by "step wedge". Is it the negative step wedge or is it the Grey Scale printed on cardboard? The Grey Scale is rather limited in contrast when compared to a normal subject. The span is only some 4 stops if I remember correctly. So a "correct" rendering of the Grey Scale, spanning from black to white in a print would indicate a negative contrast that's too high for a normal subject.

If you photograph a colorless surface - white or gray - and expose as indicated by the meter, and you develop for a negative density of 0.70, you have a good balance between exposure and developing. If the contrast is somewhere around normal, you have a very good starting point for shooting with a camera metering an average of the subject.

To connect the negative process to the printing process, you have to use the basic exposure, as described by juan in this thread. This procedure is not - repeat: not - very exact. But it it nevertheless very useful. Neither is the term "grade 2" for enlarging paper exact. It depends on the paper, the filter, the light system of the enlarger and more.

To make matters as simple as possible I would suggest:

1: With Fuji Across 100, I'm pretty sure that a normal contrast can be found at an EI of 50. Maybe a little higher, but start at EI 50.

2: Make a test for middle grey using EI 50 and find the developing time that gives a negative density of app. 0.70 (just somewhere between 0.65 and 0.75).

3: Put film in the camera and go photographing subjects that you consider to be of normal contrast. Develop and print and see how it works.

4: If it works, use that process, and go on exploring film and developing when you feel the need.

Good luck!

j-fr

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Donald Miller

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You are getting about a dozen different theories from as many different people. These theories are based in the understanding of each of these people. In fact, based upon the Ansel Adams recommendations, you are beginning with the wrong criteria for determing a film speed point. That in large part is the reason that those who use the Zone System routinely find that the film speed is lower then the manufacturers rating. I am suggesting that it is not the manufacturers rating that is routinely erroneous...it is that the wrong methodology is embraced in the Zone System.

There are a couple of threads where this erroneous criteria is discussed here at quite some depth.

The Zone system is flawed. Yet there are and have been some wonderful prints that have been produced in using it.

If you want to photograph using criteria that is based in sound sensitometric principles, I suggest that you go back to the criteria that the manufacturers of the materials universally use.

That criteria is not .10 over B+F as the film speed determiner ...nor is it starting at Zone V...Both of which have some serious failures in criteria and methodology...If you attempt to build a structure, you had best have a sound foundation under it.
 

L Gebhardt

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First get your development down. Film speed is dependant on development.

Once you have the developement locked down then you can shoot the gray card and look for the Zone I density of .1 over FB.

To help with this I use the BTZS software, but it is also possible on paper.
 

Roger Hicks

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Donald Miller said:
That criteria is not .10 over B+F as the film speed determiner
Dear Don,

Um...

Yes it is. At least for ISO speeds (based on post-1959 ASA). This is the left-hand speed point and the right-hand speed point is 1.3 log exposure units to the right; this second speed point must give a log density exposure of 0.8, correspomding to a gamma of approximately 0.615.

The ISO speed is the exposure E at the speed point (0.10 above fb/f), in lux-seconds, divided into 0.8.

What other figure had you in mind? I can only imagine that I have misunderstood you.

Of course, ISO and the Zone System are not necessarily congruent, and you are absolutely right that Zone V is mentioned nowhere in ISO standards; nor is any of the Zone System.

Cheers,

Roger
 

L Gebhardt

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Roger Hicks said:
But because of the choice of speed point of 0,10 and gamma of approximately 0,62, the variation is surprisingly less than might be expected.

Cheers,

Roger

That seems to depend on the film and how far off you were with your first guess. I still think it is easier to nail the contrast range (development) and then adjust exposure (film speed). The otherway there can be alot of circular testing.

Larry
 

Roger Hicks

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Dear Larry,

Sure, I wouldn't argue, and I would cheerfully second the point about getting contrast (= development) right first. It's just intriguing how little difference development makes to the actual ISO speed, because of that very clever choice of speed point and gamma.

If you start out with the manufacturer's ISO you'll be very close to the true ISO speed, but of course another speed (usually lower, very rarely higher) may well give you results you like better.

As I said elsewhere, my rule of thumb (except with a spot meter, where I start out at ISO) is to rate the film 1/3 to 2/3 stop slower, but much more than 1 stop in speed reduction, half ISO, should unless you are using a speed reducing developer lead you to examine each step in the procedure.

Cheers,

Roger
 

Daniel_OB

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What one should to do if density in zone I (or II....) is 0.1 and at the next zone (say zone II) is 0.11????? Hex, this is a pitfall with zone system and iso too.

What is for photography important is not just density but the SLOPE of the curve too. How to set the standard for both? That is the ?.

www.LEICA-R.com
 
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Willie Jan

Willie Jan

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Daniel_OB said:
What one should to do if density in zone I (or II....) is 0.1 and at the next zone (say zone II) is 0.11????? Hex, this is a pitfall with zone system and iso too.

What is for photography important is not just density but the SLOPE of the curve too. How to set the standard for both? That is the ?.

www.LEICA-R.com

i measured the density of a kodak gray step card i made a photo of after printing.
The (white) was 0,14 (should have been 0,04 = agfa mcp310 paper)
The M (zone V) was 0,7 (is fine)
The B was 1.70 (=number 16) should be 1.6

So this also showed my curve as a circel which was ok at zone V.
What to do next to get this fixed?
Because the white was not white enough should i develop longer to ge a higher density, or agitate more?
 

L Gebhardt

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Willie Jan said:
i measured the density of a kodak gray step card i made a photo of after printing.
The (white) was 0,14 (should have been 0,04 = agfa mcp310 paper)
The M (zone V) was 0,7 (is fine)
The B was 1.70 (=number 16) should be 1.6

So this also showed my curve as a circel which was ok at zone V.
What to do next to get this fixed?
Because the white was not white enough should i develop longer to ge a higher density, or agitate more?

If I understand you correctly you are trying to get the 3 points (white, black and gray) to the target values. It is very unlikely that you will ever get this to work exactly because the curve shape of the paper and the film may not allow it. Two points matching is easy and what I would shoot for. Most film testers seem to aim to match a shadow point and a highlight point. The middle gray will fall where it falls. If the middle tones and the highlights are most important to your images I would try and get development targeted to give you the correct spread between .7 and .6 and let the shadows fall where they may.

From your numbers it looks like if you printed with slightly less time your shadows and highlights would come out about right. But your middle gray would be too light. You could try another paper, increase your film development a bit, change your development technique, try another paper developer, increase the paper grade (filtration).
 

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Willie, longer development or increased agitation will have the effect of raising contrast. Without a densitometer, I'm not sure how the shape of the curve can be affected by changing the method of increasing contrast. More tests! tim

P.S. You really must get a 4x5 camera and some sheet film soon, you are heading into danger with these tests!
 
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Willie Jan

Willie Jan

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noseoil said:
Willie, longer development or increased agitation will have the effect of raising contrast. Without a densitometer, I'm not sure how the shape of the curve can be affected by changing the method of increasing contrast. More tests! tim

P.S. You really must get a 4x5 camera and some sheet film soon, you are heading into danger with these tests!

i am already using 4x5 :D, but we are investigation how we can make a good test for our photclub members for 35mm and 120 format to find out how to test there film. it's getting more and more confusing....
 

Donald Miller

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Roger Hicks said:
Donald Miller said:
That criteria is not .10 over B+F as the film speed determiner
Dear Don,

Um...

Yes it is. At least for ISO speeds (based on post-1959 ASA). This is the left-hand speed point and the right-hand speed point is 1.3 log exposure units to the right; this second speed point must give a log density exposure of 0.8, correspomding to a gamma of approximately 0.615.

The ISO speed is the exposure E at the speed point (0.10 above fb/f), in lux-seconds, divided into 0.8.

What other figure had you in mind? I can only imagine that I have misunderstood you.

Of course, ISO and the Zone System are not necessarily congruent, and you are absolutely right that Zone V is mentioned nowhere in ISO standards; nor is any of the Zone System.

Cheers,

Roger

Roger,

With all due respect, I beg to differ with you. I have taken the liberty of copying and pasting an earlier post by Stephen Benskin, who has done a great deal of study on this matter. Perhaps this will explain what I am addressing.



--------------------------------------------------------------------------------

Quote:
Originally Posted by ElectricLadyland

basically i dont see why having the EI precisely what it is matters or is beneficial, becasue curves vary between films so even same EI films will have differnt tones for the same exposure... but i thik what is important is knowing that at any given EI for a particualr film, this meter reading and developer/time will develop to this tone. what are some thoughts on this?


Quote: Stephen Benskin

Excellent observation. The fixed density method of the ISO standard is really a short cut, and the Zone System fixed density method is conceptually flawed. Most people just want to know just enough to make something work. They usually aren't interested in the reason why.

Without going into great detail, the most accurate speed method is based on the gradient of the curve and not a specific density. It's call the Fractional Gradient Method. Todays ISO standard is representative of this method except it uses a fix density short cut method. Lyod A. Jones determined, after extensive testing, that consistently high quality negatives are produced when the speed point is at a point on the curve where the gradient is 0.3x the average overall film gradient. In many cases, this isn't at 0.10 over fb+f.

With this in mind, using any fixed exposure or density method of print determination is also counter indicated since there isn't a specific base density in the negative to key on.
 

Roger Hicks

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Dear Don,

I cannot read Stephen's post in any other way than that the ISO standard uses fixed density ('The fixed density method of the current ISO standard...')

I have done a great deal of study on this matter too, including talking to a member of the ISO standards committee. Stephen and I are saying exactly the same thing, and I make substantially the same point on pp. 35-36 of 'Perfect Exposure', David & Charles/Amphoto 1999. Both he and I argue that fixed density is inferior, but regardless of that, the 0,10 figure is the ISO standard.

In fact, Stephen was recently kind enough to send me a copy of an as yet unpublished paper on the relationship between the two criteria. I hope he finds a publisher as it is a brilliant analysis.

Cheers,

Roger
 
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