Zone I develop question

Donald Miller · Jun 30, 2006

Roger,

Apparently you failed to read the part that says that Jones determined the speed point to be most accurately determined by assigning a value of .3 of the average gradient of the film

The reason that the .10 speed point is not accurate is that the speed point will vary with the gradient of the curve. I recognize that you may not have printed in any of the processes apart from pure silver enlarging.

When one moves into the processes that require a higher density range and a different gradient then the .10 speed point becomes a very nebulous criteria. Now is this variance that occurs with a different gradient a difficulty with the process or is this variance a difficulty because the determining criteria is flawed. I will leave it for you to determine.

Roger Hicks · Jun 30, 2006

Dear Don,

No, I didn't fail to read that bit, and I have used several other processes including POP, Argyrotype and gum bichromate. I am slightly miffed at your suggestion that I would argue in this fashion if I were as ignorant as you appear to think.

All that I (and Stephen) say is that 0,10 above fb+f is, in fact, the ISO criterion. You cannot, therefore, call it inaccurate with respect to ISO speed. The big argument for 0,10 is that under ISO conditions it does, in fact, come very close to the fractional gradient criterion. Steve has demonstrated this to his satisfaction and mine (mone is not as demanding as his in this area).

The overall density range of the negative does not affect the validity of 0.1 as a handy minimum density: you can use less or more, but anything above 0,03 or thereabouts is printable in a contact print. The upper point is of course very little affected.

I fully take your point about different gammas, and cheerfully accept that more development will give a higher density for a given exposure, but this doesn't matter. You get more density for a given exposure with a higher gamma, and as long as you have adequate minimum density, a bit more won't hurt. In other words, yes, you could cut the exposure a bit, but why bother?

Besides, when you stop using a film in the way that its manufacturers (and the designers of the ISO standard) envisioned, yes, things change. But they would, wouldn't they? Again, there's a fair summary of the assumptions (and why they aren't always valid) in Perfect Exposure.

Cheers,

Roger

Stephen Benskin · Jun 30, 2006

Both of you guys are on the same page. Even though the ISO standard uses 0.10 to determine film speed, it doesn't indicate that that is where the shadow exposure falls. The fixed density of 0.10 isn't the only part of the criteria. Don't forget the value of 0.80 for the delta D. When these conditions are met, the ISO standard will produce a film speed as accurate as the fractional gradient method. The supporting papers to the ISO standard state that the use of the fixed density method without incorporating what is known as the Delta X criterion on any film processed outside of the standards contrast criteria will not produce accurate film speeds. What the standard doesn't state is that the Delta X criterion equation is built into the ISO standard when the conditions are followed.

One of the things that cause much confusion to many photographers is that the standards aren't supposed to explain any theory. They are designed to be a procedural "blueprint". I believe they should at least have an appendix for the theory. In reality, some don't even offer a bibliography.

Since the manuscript I wrote probably won't be published, I will be happy to send a copy to anyone interested. Just drop me an email. The way things are going lately with magazines and traditional photography, I feel like a blacksmith after the introduction of the automobile.

Roger Hicks · Jun 30, 2006

Dear Steve,

Thanks for chiming in. I was uncertain about how much to disclose on your fascinating paper. Your offer to share it is extremely generous.

Cheers (and happy blacksmithing),

Roger

Donald Miller · Jun 30, 2006

Hi Steve,

Thanks for chiming in. I will send you an email to gain a copy of your manuscript. Thanks for your services to photography.

L Gebhardt · Jun 30, 2006

Stephen Benskin said:
Since the manuscript I wrote probably won't be published, I will be happy to send a copy to anyone interested. Just drop me an email. The way things are going lately with magazines and traditional photography, I feel like a blacksmith after the introduction of the automobile.

Maybe you could publish it here.

Stephen Benskin · Jun 30, 2006

L Gebhardt said:
Maybe you could publish it here.

Good idea. That would make it easier for everyone. Just tell me how.

Until then, my email address is SteveB6465@Aol.com. The document is a pdf.

L Gebhardt · Jul 1, 2006

To publish it here as a pdf you could create an article and attach the pdf.

To create an article:

Go to the Community menu and select Articles.
The choose the best category, probably How To.
Then select New Entry at the bottom.
You could then write up a brief summary and attach the pdf.

Stephen Benskin · Jul 1, 2006

L Gebhardt said:
To publish it here as a pdf you could create an article and attach the pdf.

To create an article:

Go to the Community menu and select Articles.

The choose the best category, probably How To.

Then select New Entry at the bottom.

You could then write up a brief summary and attach the pdf.

There's a problem. I seem to have exceeded my upload quota.

dancqu · Jul 2, 2006

I shoot 5 zones; 3 through 7. Those are the ones that
print. No need to change f stop. Stay away from reciprocity
failure. Add a clear blue sky and white to gray board. Dan

Ray Heath · Jul 2, 2006

gee fellas, this maybe really simplistic, and i'm sure i'll be villified, but how about you actually go outside and take some pictures using the manufacture's ISO and chemicals, then assess the results and adjust the ISO next time you shoot

it doesn't have to be rocket science

Roger Hicks · Jul 2, 2006

Ray Heath said:
gee fellas, this maybe really simplistic, and i'm sure i'll be villified, but how about you actually go outside and take some pictures using the manufacture's ISO and chemicals, then assess the results and adjust the ISO next time you shoot

it doesn't have to be rocket science

Dear Ray,

Actually TAKE PICTURES? And then PRINT THEM? HERETIC! BURN THE WITCH!

Cheers,

Roger (www.rogerandfrances.com)

dancqu · Jul 2, 2006

Ray Heath said:
...actually go outside and take some pictures ... assess
the results and adjust the ISO next time you shoot...
it doesn't have to be rocket science

Adjust the ISO and/or development. As has
been mentioned contrast must be considered.

How ever many exposures are made, the 5 I've
mentioned or more, the rest of the roll can be used
to shoot red, green, and blue Sturdy Boards for a
check of the meter's color response. Dan

BBarlow690 · Jul 2, 2006

j-fr said:
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

www.j-fr.dk

Well, then, help me out. I have both the top and the bottom correct, and my Tri-X negatives are uniformly gorgeous, with exceptional separation in the low and high values. My proofs are lovely and the pictures print easily. So what's wrong? "Out to lunch" is not a term I can recognize in my pictures. Could you be a little more specific? And what is the middle "too low" for?

And what's the alternative to:
- Testing for proper Zone I exposure (which yields "true" film speed for my film, developer, and shutters?
- Testing for proper development time that yields Zone VIII negative density, and thus value VIII in a print exposed for minimum time to yield maximum black through clear film?

I guess I've had it wrong for 25 years...

Bruce Barlow
www.circleofthesunproductions.com

Stephen Benskin · Jul 2, 2006

Actually, testing for Zone I exposure doesn't yield true film speed, but it is a perfect example of the the strength of photography and cause of constant debate. Photographic parameters are based on the perception of quality. Not only does the concept of what constitutes quality is variable, but scientific psychophysical testing must make certain assumptions. The first excellent print test was based on what best represented an accurate depiction of the scene. This excludes anyone who wants to interpret the scene differently. So, does the concept of film speed based on the first excellent print tests have the same relevance?

Another example of the changing perception of quality is with portraiture. In the 20s, 30s, and 40s, the ideal tonal value of women's skin tone was a close approximation of their skin tone in real life. Men's ideal was darker than real life. A popular approach is to use a green filter on men to produce "bronze" life skin tone. Since then the ideal skin tone has progressively lightened. Each look takes different techniques including degree of processing and choice of paper grade. Neither perception of quality is incorrect, but the concept of photographic "normal" would change depending on which condition was standardized for the testing.

As for Zone I testing, ZS states that it falls four stops below the meter reading. ISO bases it's film speed at 3 1/3 stops below. Zone System approach amounts to film speeds consistent with the pre 1960s film speed standard which contained a large safety factor (another example of the reason why so many "systems" tend to work). Film speeds almost doubled because of the change, yet the ZS never changed its testing conditions. Both work. Both yield quality negatives, but I think we have to rethink what is considered "true" film speed.

Ray Heath · Jul 3, 2006

can you guys show examples of these techniques and the increases in negative quality

BBarlow690 · Jul 3, 2006

Ray Heath said:
can you guys show examples of these techniques and the increases in negative quality

I'm not sure what I'd show you. Bad exposures vs. good? Poor shadow separation vs. good? Blocked highlights? All errors from the above in one print? I've seen them all in student work, and remember a time in my life long ago. I hope to do a DVD on film testing. Good idea: I'll make bad examples so folks can see what bad stuff looks like compared to better stuff. Thank you for the idea. I don't pay royalties...

Mostly what my way does for me is eliminate any doubt that what I'm doing will work. I don't want my head cluttered with technical mishmash when I'm trying to make an expressive photograph. I want technical methods that are simple, reliable and repeatable. One film, one film speed, one basic development time (well, two, if I need more contrast in the scene). There are enough variables in the real world that doing this will get me far enough into the ballpark to produce a printable negative every time, and trying for any more precision is probably cancelled out by variations in shutters, lightmeters, my metering technique, developer dilution, temperatures, paper variations, paper developer oxidation, blah blah blah. The PERFECT negative is produced by luck. Mine only have to be good enough for photography.

The notion presented about about rethinking 'true' film speed sounds like a good thing to spend a lot of space talking about, but I'd rather use it. If measuring 4 stops below rather than 3 1/3 yields a doubling of film speed, for the kinds of pictures I make I'm all for it. I'm also for it because it works for me, regardless of the science or what the ISO people (who probably are not photographers...) decide to do. Yup, they build in a safety margin because people haven't tested and learned what their materials are doing.

Ditto development time. If my development time takes me to the limit of the materials, and permits me to easily print good shadows with crisp, delicate high values at the start, subject to interpretation at my whim, I'm hard pressed to understand why it's being suggested that somehow I'm wrong. I can tune the time to different papers, such as Azo (and, we hope, its replacement), easily, and know that what I'm doing will work with the materials I'm using.

And yup, maybe tastes have changed over the years and some no longer like men's portraits through green filters. So be it. I'm not sure how that's relevant to getting exposure and development right. Someone please set me straight here.

So, if I'm still wrong, would someone please enlighten me with concrete, practical suggestions about how I might improve what I'm doing?

Bruce Barlow
www.circleofthesunproductions.com

Stephen Benskin · Jul 3, 2006

Bruce,

I'm not suggesting you are doing anything wrong. The "rethink" wasn't about changing anyone's techniques but how we think about film speed. I was talking about the acceptable range of variance and the illusion of control that any "system" offers. In a long winded way, I was saying there is not "true" film speed. You have just misread the meaning of my post.

We are in agreement about all the variables. In fact, personal preferences in metering technique and flare have the greatest influence on precision shadow placement.

Ray,

All natural systems have a range of variable that can be graphed in a normal distribution curve. In photography, the idea is to use a technique that will give you the greatest success in the greatest number of situations. The average luminance for a daylight scene is 7 1/3 stops and the illuminance remains rather consistent through the mid-morning and mid-afternoon. These conditions are what are considered normal. If you standardize you techniques for these conditions, you will produce acceptable images most of the time.

My first camera was a pocket instimatic and it produced "good" exposures the majority of the time, and it didn't have any metering capability what-so-ever. The "superiority" of any technique is through its consistency and not by any one example.

The fractional gradient technique is a superior approach to film speed not because it's obvious with each and every exposure, but because of those outside the norm occasions.

Ray Heath · Jul 3, 2006

yeh right Bruce, but is this not a 'visual' medium, give me a visual, not more meaningless words

Roger Hicks · Jul 3, 2006

Ray Heath said:
can you guys show examples of these techniques and the increases in negative quality

On screen? Not a hope.

In prints, in person? Maybe, sort of. But a good printer can often make a better print out of a lousy negative than a bad printer will make from a good one. And different photographers' interpretations of what is a good negative can vary too.

What most people are saying is, "This has worked for me." Often they can add "It has worked for quite a lot of other people too."

Ultimately it comes down to your choice about whether to try something different, or to stick with what's already working. It's a judgement call whether a particular piece of advice is likely to get you better pictures, or worse. And the latter can happen!

Cheers,

Roger (www.rogerandfrances.com. Take a look at the free modules in the Photo School on the site, especially 'Why we don't use the Zone System' and 'ISO Film Speed')

BBarlow690 · Jul 3, 2006

Ray Heath said:
yeh right Bruce, but is this not a 'visual' medium, give me a visual, not more meaningless words

Still struggling, Ray. What do you want to see?

And I'd appreciate understanding how my words are "meaningless." That comment seems gratuitously insulting, given that I'm trying to help.

Steve, we agree on the variables clobbering any notion of perfection. "Close enough for photography."

Bruce Barlow
www.circleofthesunproductions.com

Ray Heath · Jul 3, 2006

g'day Bruce, i didn't intend to sound insulting, i'm still working on my net etiquette, sorry

i just meant that without a visual to explain a visual concept i can't put a lot of faith in just words

i understand and totally agree that a computer monitor is not the best way to display quality prints, in fact in my photography classes i like nothing better than to pass around real prints and to see the looks of surprise and delight on my students faces, i actually tried a computer slide show, it just don't cut it

but not all the concepts we are discussing are about print quality, they are also about image quality, and surely some of these effects will show to some degree on a monitor

i can't believe that comparison prints would not show some of the effects when displayed together on screen, sure they may look less than ideal, but if you show a great print/image and poorer print/image they will have the same amount of less than perfect and the comparison should still be obvious

BBarlow690 · Jul 4, 2006

Hi, Ray, apology accepted, and thanks.

I can try to put something up, hampered by my technological incompetence and our dial-up connection. I don't think I have any bad ones, however, so I'm not sure how we can get a comparison. Whatever it is, it will be fairly low-resolution, the family won't let me tie up the phone til Friday uploading.

It's apropos to this discussion, but I find with workshop students...and myself...that we often haven't developed our eyes enough to know what good stuff really looks like. In that vein, I have trouble with those who say "Make pictures, and if it doesn't look right, change it," because too many don't know what "right" is. The method I describe uses references that are pretty hard to miss, and once used, should yield the right stuff.

OK, I'll see what I can conjure.

Bruce Barlow
www.circleofthesunproductions.com

BBarlow690 · Jul 4, 2006

I'm at home at APUG, being technologically incompetent, as shown with the following mediocre scans. I don't do Photoshop, as a rule.

The rocks and water show good low value separation in the dark rocks (which may not come through on a screen), and high value separation in the white water (ditto whether it shows). This was a straight print - no burning or dodging. What you see in the final print is what the negative contained. Disgustingly easy to print, thank the Lord. Right ISO, right development time, close enough exposure in the field. I probably adjusted the print exposure down to 1-second increments to get the whites right. Ilford Multigrade, grade 2, 10 percent dry down factored in for final prints.

The sheep is from a 35mm negative exposed using the averaging meter in the camera. The whites are blown out - playing with Photoshop I can get no texture in them at all, which could demonstrate either oversxposure (wrong ISO), or overdevelopment (wrong development time). Or both.

Well, that's about the best I can do for examples, particularly lousy ones. Hope this helps a little

Donald Miller · Jul 4, 2006

Bruce,

Thank you for providing these scans. I hope that you will permit my observations here. I would comment that in your rock and stream image, the one that you say is easy to print, that the local contrast is lacking in large measure. The overall contrast is almost there. Deep values to high values approximate the paper grade chosen.

But the image has no "life". The internal tonal separation in the low values is muted. It seems on my monitor that this condition also exists on the other end of the tonal spectrum The highlights seem to be blown out too. Is this a work print in progress?

How do you propose to get local contrast...the elusive glow to an image like this?

Zone I develop question

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