getting a personal EI without an enlarger or densimeter?

[Stephen Benskin]

I don't know if I need to know this or not but I at least want to investigate it. Please point me to sources of "the right things". What is your suggested reading list?

Photographic Materials and Processes
Beyond the Zone System
Sensitometry for Photographers
Photographic Sensitometry: The Study of Tone Reproduction
Way Beyond Monochrome
The Theory of the Photographic Process, 3rd Edition
The Manual of Photography: Photographic and Digital Imaging
Exposure Theory and Practice
Exposure Manual
All of the papers in the Defining K link

 

[RobC]

His head will explode if he reads all of those. Mine did and I only read half of them before I said enough is enough...

 

[Xmas]

Photographic Materials and Processes
Beyond the Zone System
Sensitometry for Photographers
Photographic Sensitometry: The Study of Tone Reproduction
Way Beyond Monochrome
The Theory of the Photographic Process, 3rd Edition
The Manual of Photography: Photographic and Digital Imaging
Exposure Theory and Practice
Exposure Manual
All of the papers in the Defining K link

Hi Stephen

or the last two sentences of post #135.

Noel

 

[Stephen Benskin]

hi michael
no, not kidding ..
i've never read threads where someone trash talks sensitometric / density / ZS sorts of stuff
and then asks questions on what zone to place things. i guess maybe i just don't read those threads ?
i have heard of barnbaum ( i think ) but i haven't ever
read anything that he has written or seen his work, sorry i don't really follow the big names

There are variations to the statement and it changes depending on the technical level of the photographer. Mostly it's just a defense mechanism. The beginner will claim the technical nature of the Zone System will get in the way of their creativity. The Zone System practitioner will claim the same thing about Beyond the Zone System, and so forth. One of my favorites is "I would rather be spending my time shooting." Like there has to be a choice.

In the first edition of The Negative, Adams seems a little at odds with sensitometry. p 51 "Is it not more logical to leave gamma to the sensitometrist and manufacturer, and to think of negative development in terms of a simpler symbol? X minutes at Y degrees temperature would represent “normal” with consideration for the photographer’s concept, lens, film, film developer, methods of printing and enlarging, and the paper used." p 10 "While of utmost importance to the chemist, physicist, and manufacturer, sensitometry in its usual aspect does not concern the practicing photographer."

 

[Stephen Benskin]

Hi Stephen

or the last two sentences of post #135.

Noel

Do you seriously consider that Kodak publication a good "start by learning the right things"? Come to think of it, there are a couple of books on my list that I can't recommend 100%.

 

[Stephen Benskin]

Using ISO speed and recommended dev using stock solution will give you approx 7 1/2 stop range from black to white which will print on grade 2.

Quick and dirty zone system calibration:

Using half the ISO speed and reducing dev by 30% will give you approximately a 10 stop range from black to white which will print on grade 2.

Can you help me unpack this? Are you claiming a 30% reduction in development equals N-2.5? Or are you using two different scales for the results - paper D-max to paper white for the 10 stop range, and 0.04 above paper base to 90% D-max for 7 1/2 stop?

 

[rbultman]

Quick and dirty zone system calibration:

Using half the ISO speed and reducing dev by 30% will give you approximately a 10 stop range from black to white which will print on grade 2.

I can't help but think that this is close to being dead on judging from the number of people that end up shooting at this EI. Or, they are just a bunch of lemmings...

Regards,
Rob

 

[rbultman]

Follow Kodak's procedure on page 12 of publication O3.

Thanks for pointing this out again. Very simple. It is interesting that in the example they give, TMAX 400, they show and EI of 200. I realize that these are not actual test results but I can't help but wonder if even Kodak "knows" that most people that do testing of this nature will end up shooting 1/2 box speed.

Regards,
Rob

 

[Photo Engineer]

My entire life has followed the guidelines below:

1. Expose B&W at box speed and process for the mfgrs recommended times for that film.
2. Expose color pos at box speed and process normally.
3. Expose color neg over by 1/3 stop or up to box speed and process normally.

If I want to do sensitometry, I do, and look for:

1. B&W and color neg at a gamma of 0.6 - 0.7
2. Color pos at 1.5 - 1.7.

If the results look odd from the first list or second, I check my process. I have thousands of B&W and color that attest to the above 3 methods working and I have never used the zone system or sensitometry BEFORE the fact, except in experimental coatings. And of course, that is a must do there. When you are making your own, you have to find out what you did with the coating first.

Now, on to the Kodak data sheets on line. The most accepted and best sensitometry is also generally the best curve and has a gamma or contrast or slope (same things really) in the range I have stated above.

All this fuss when the mfgr does it for you?

PE

 

[rbultman]

Lets assume for a moment that you are doing a portrait and that you want to peg a specific point on the face at a specific density on the print...

Thanks for that explanation.

Regards,
Rob

 

[rbultman]

Beyond the Zone System
Way Beyond Monochrome

Thanks for the list. Of the two in the condensed list above, which one would you recommend as being the easiest to follow?

Regards,
Rob

 

[RobC]

Can you help me unpack this? Are you claiming a 30% reduction in development equals N-2.5? Or are you using two different scales for the results - paper D-max to paper white for the 10 stop range, and 0.04 above paper base to 90% D-max for 7 1/2 stop?

Nope, I' claiming no such thing becasue it isn't using any thinking of that kind. By reducing ISO by half you are getting an extra stop of shadow detail at the bottom end and by reducing dev by 30% you are bringing zone 9 into grade 2 territory. Its ball park and not science or related to any sensitometric measurements. QUICK AND DIRTY as I said.

 

[Stephen Benskin]

All this fuss when the mfgr does it for you?

And that is why so many people get good results without having to understanding the Zone System or sensitometry. A lot of very smart people have already done the work.

Thanks Ron for pointing that out.

 

[Stephen Benskin]

Thanks for the list. Of the two in the condensed list above, which one would you recommend as being the easiest to follow?

Regards,
Rob

Those are the two I can't recommend 100% I disagree with some of Ralph's ideas on tone reproduction, and how Davis tends to over-simplify certain concepts in order to fit them nicely into a system. If you want to understand how sensitometry and tone reproduction works with the Zone System, Davis is the way to go. He is pretty solid on theory. Ralph's book has a broader scope and doesn't go into as much detail on those subjects.

 

[rbultman]

Those are the two I can't recommend 100% I disagree with some of Ralph's ideas on tone reproduction, and how Davis tends to over-simplify certain concepts in order to fit them nicely into a system. If you want to understand how sensitometry and tone reproduction works with the Zone System, Davis is the way to go. He is pretty solid on theory. Ralph's book has a broader scope and doesn't go into as much detail on those subjects.

I was afraid you might say that.

Thanks for the recommendation.

Regards,
Rob

 

[Bill Burk]

Nope, I' claiming no such thing becasue it isn't using any thinking of that kind. By reducing ISO by half you are getting an extra stop of shadow detail at the bottom end and by reducing dev by 30% you are bringing zone 9 into grade 2 territory. Its ball park and not science or related to any sensitometric measurements. QUICK AND DIRTY as I said.

I'm sure a quick and dirty rule like that will work.

But looking at my graphs, 30% reduction... Takes me from 0.62 to 0.45 Contrast Index. For Grade 2 paper, this is suited to 9 stops subject brightness range, which I like to equate to N-2... Not very often that I need N-2.

So sure... Quick and Dirty - half rated speed is great... but don't knock off that much from the normal development time.

 

[Bill Burk]

I was afraid you might say that.

Thanks for the recommendation.

Regards,
Rob

Get them both anyway. Buy Way Beyond Monochrome directly from Ralph Lambrecht.

 

[Stephen Benskin]

Nope, I' claiming no such thing becasue it isn't using any thinking of that kind. By reducing ISO by half you are getting an extra stop of shadow detail at the bottom end and by reducing dev by 30% you are bringing zone 9 into grade 2 territory. Its ball park and not science or related to any sensitometric measurements. QUICK AND DIRTY as I said.

You have two different subject luminance ranges fitting onto a grade 2 paper with a range from black to white. One has a 7 1/2 stop luminance range (BTW, normal is based on 7 1/3 stops). The other has 10 stops. You are implying that by reducing the development time by 30% for the ten stop scene it will result in the same negative density range as the 7 1/3 stop scene processed normal.

Example 1: 7 1/3 stop subject luminance range, Negative Processing time 7 min, CI 0.58 (Normal), Negative Density Range 1.05, Paper LER 1.06, Paper Density Range 1.88



Example 2: 10 stop subject luminance range, Negative Processing time 5 min, CI 0.46 (- 30%), Negative Density Range 1.28, Paper LER 1.06, Paper Density Range 2.12



Example 1: NDR 1.05, PDR 1.88
Example 2: NDR 1.28, PDR 2.12

They are not equal.

BTW, Time/Gradient curves are different for each film/developer combination. Changing the percentage of the processing time can produce very different results. Some form of average gradient is the most accurate way to communicate a target contrast.

 

[MattKing]

I'm not that fond of reducing development as a standard practice.

Personally, I prefer to start with a negative with good midtone contrast, and use the tools available to the darkroom printer to deal with the highlights. And with the shadows too, if necessary.

I don't mind increasing the exposure a bit, when I'm using a film like TMY-2.

 

[Stephen Benskin]

Bill,

Here is a chart of different developmental models. I prefer the Practical Flare Method.

 

[removed account4]

There are variations to the statement and it changes depending on the technical level of the photographer. Mostly it's just a defense mechanism. The beginner will claim the technical nature of the Zone System will get in the way of their creativity. The Zone System practitioner will claim the same thing about Beyond the Zone System, and so forth. One of my favorites is "I would rather be spending my time shooting." Like there has to be a choice.

In the first edition of The Negative, Adams seems a little at odds with sensitometry. p 51 "Is it not more logical to leave gamma to the sensitometrist and manufacturer, and to think of negative development in terms of a simpler symbol? X minutes at Y degrees temperature would represent “normal” with consideration for the photographer’s concept, lens, film, film developer, methods of printing and enlarging, and the paper used." p 10 "While of utmost importance to the chemist, physicist, and manufacturer, sensitometry in its usual aspect does not concern the practicing photographer."

people are funny, aren 't they ?!

i only agree with what people / manufacturers say to a certain point .. i don't use their lenses, shutters, developers, or anything else ...
not sure why anyone would invest in anything without a "dry run"

 

[removed account4]

John, it permeates nearly every thread having to do with films, developers, processes and printing. People like to talk about the "tonalities" of different films and developers, the "real" speed of film x, how reduced agitation does this or that etc. This is all sensitometry. But dare to present some sensitometric data or theory which might show what is happening vs what someone thinks is happening, and all of a sudden they're not interested in technicalities anymore.

Anyhow, I've written way too much in this thread so I'll leave it to the rest of the participants at this point.

i don't see it like that at all ..
maybe i am not as invested as you
or don't care ...

 

[Bill Burk]

I follow a most useful chart in the darkroom when I prepare to develop a roll of film.

This is my Time/Contrast chart.

While I claim I am able to develop film to any contrast I want, the scatter points reveal the harsh reality.

It's a good thing that I do not offer my services to others. "Let me scratch your film" would be my motto.

It does appear that my laboratory is not under control. But I know how far out of control I am and I can do something about it.

There are two points I would like to explain about this graph.

1. Underdevelopment is the most common error in my darkroom. So I would not want to deliberately aim low, because I might hit lower still.

2. Despite missing my aimed contrast very often and significantly, all the negatives I developed are easily printable. There is that much tolerance in the black and white negative process.

 

[Bill Burk]

Bill,

Here is a chart of different developmental models. I prefer the Practical Flare Method.

View attachment 114436

I still prefer the format of this chart that takes SBR and LER to determine CI. I think we concluded it's fixed flare 0.4

( (there was a url link here which no longer exists) )

 

[Stephen Benskin]

I still prefer the format of this chart that takes SBR and LER to determine CI. I think we concluded it's fixed flare 0.4

( (there was a url link here which no longer exists) )

I remember putting together a spreadsheet with the practical method. But I did upload the Kodak version too which was a fixed flare of 0.40. I believe my paper on development shows how the fixed flare model is too extreme with the higher pushes.