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Alan Johnson

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I appreciate your doing this, as it's always good to have reviewers check one's work. Some questions:

* How do the densities of the two negatives compare? My goal was twice XTOL's dev-time, and I'm wondering how close I got for a conventional grain film.

* Could you compare grain by viewing the neg's directly with a loupe? I've found that even a dedicated film-scanner as good as my Nikon Coolscan IV ED does not reliably show grain due to focus-variation, so I trust direct viewing in a loupe or microscope more. Hmm, I guess a couple of carefully-focused extreme enlargements (projecting onto the floor?) would also clearly show the grain-difference.

* I notice that the area under the bumper is darker in the Xtol-scan, indicating a difference in black-point and/or gamma in the scans. How did you set these in your scanning software?

My goal is to get XTOL's grain in a concentrate, and I'll keep hammering at it. Feedback like this is good.

Mark Overton
(1)The density with D316 was very slightly higher than Xtol 1+1.You did a great job in formulating this concentrate,the pH was near enough spot on and you managed to dissolve a lot of AA by using the metaborate first.
(2)IMO the most reliable way to assess grain is with an enlarger,which I don't have time to do.However I know my V700 will easily pick up the difference between Perceptol and Xtol.I would be surprised if my conclusions are wrong.
(3)Good spot. But I might get cast into the outer darkness for answering that on APUG.
(4)I did wonder if you could make a very strong concentrate that would give a working solution closer in composition to Xtol ,which working solution could be re-useable by throwing out and replenishing 70ml each time.
But already the solubility limits are approached.
 
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albada

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(...) and you managed to dissolve a lot of AA by using the metaborate first.

You are perceptive! Yes, I noticed that more AA would dissolve into PG if I first dissolved metaborate, which converts some of the AA. You're onto my tricks. :smile:

(3)Good spot. But I might get cast into the outer darkness for answering that on APUG.

We hate to see you weeping and gnashing your teeth, so we'll drop that.

(4)I did wonder if you could make a very strong concentrate that would give a working solution closer in composition to Xtol ,which working solution could be re-useable by throwing out and replenishing 70ml each time. But already the solubility limits are approached.

Which gets back to my original goal: Make a concentrate that gives XTOL's image-quality, with sulfite added separately (for now). I even tested a concentrate that copied XTOL closely, and it worked well. I won't post it here because that was before I had the pH-meter, and I want to measure and perhaps adjust the pH.

But then I tried to cut the sulfite in half and double the dev-time because I'm disappointed at the great quantity of sulfite that gets poured into developers. This half-and-double developer works great for TMY-2, but with your input, I'll try it with HP5+ and Tri-X. I like it because it saves chemistry and gives a high concentration, but if I can't get it to work well with a variety of films, then it'll just be for t-grain or just TMY-2. And I'm thinking I should complete the original goal before pursuing this half/double idea further.

Mark Overton
 
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albada

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Mark, It's been a long time and I can't find my recipe (...)

Jerry, your formula with half-TEA and half-PG was in my notes! You posted it to the pure-silver list long ago. I've done a lot of researching, and now I'm forgetting what all I've found. Anyway, for the record and for the sake of search-engines, here is improved PC-TEA by Gerald Koch:

TEA ....................... 50 ml
Propylene glycol ....... 50 ml
Ascorbic acid ........... 9.0 g
Dimezone S ............. 0.3 g
Potassium bromide .... 0.2 g (or 0.25)

Use 1+50 (about 9 min) as with PC-TEA. Works well: Low fog, correct contrast, very fine grain.


Mark Overton
 

Ryuji

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Does it make it worse because the iron bound by it is still or even more chemically active (like it is supposed to be in Ammonium-Ferric-EDTA) ? Or are there other effects I have not thought/learned about?

Would Dequest 2010 be better? I have a possible source for it here in Europe (Tronds knows about this).

In presence iron-EDTA complex is more active redox catalyst than iron itself. Well known and documented in electrochemistry literature.

Keep in mind that iron exists mostly in ferrous form in developer solutions, and ascorbate itself also forms complex with iron and gets destroyed very quickly.

Again, I am not allowed to comment on the works of gentleman from upstate New York. It should also be noted that he is not supposed to talk about my work or statements, at all.

In general, a certain pH-specific blend of amines plus salicylic acid was effective enough that I could keep concentrated developers for months, even when I intentionally mixed impurities and some molecular oxygen and/or peroxide. However, I wasn’t satisfied enough to stop looking. Now I have another solution that is much simpler and more effective, but the ingredient is not available from any laboratory reagent supply house (in other words, if you want to adapt this solution, you need to get the stuff from me).

Either way, denial or ignorance is not the answer.
 

Ryuji

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For reference on basic industrial chemistry (such as buffers and solvents) Ullmann's encyclopedia is always a very good start (and usually a good end as well). It's not cheap - get connected with a very good library. Your local university library may have electronic subscription. If not, as librarian for a good alternative reference.

http://onlinelibrary.wiley.com/book/10.1002/14356007

If I were to suggest just one book on general photographic chemistry written in English language, I'd say one by Keller. Each section is written by AGFA experts. It is more updated than Haist, gives more broad coverage, and offers less obsoleted, now-rejected or now-irrelevant information. Very concise so you need to read each sentence very carefully, but it is a good book. If you want to get a glance of existing body of knowledge on theory, the book by T. H. James is probably still the best in English language. Make sure to get the latest edition. Earlier one had a lot of theories/models that became obsolete/irrelevant/wrong.

But nothing is better than reading original peer reviewed papers... though you need to have a very clear bigger map before getting to appreciate details.

Then, in order to really understand the developer chemistry, you should also understand the mechanism of photosensitivity. That is, the theory of emulsion chemistry. This part changed SO MUCH MORE than the developer formulation in the past 100 years. Since the goal of any developer is to exploit latent image centers created by photosensitivity, you should have good understanding of your enemy to fight for the goal well. But I'd start with Ullman and Keller.

That said, there is an excellent book written in Japanese language, more updated than Haist and James combined, and written by mostly Fuji, Konica, and University of Chiba people. It's probably still the latest single book that is comprehensive.
 

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That said, there is an excellent book written in Japanese language, more updated than Haist and James combined, and written by mostly Fuji, Konica, and University of Chiba people. It's probably still the latest single book that is comprehensive.

You are not by any chance talking about this book?
 

Ryuji

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You are not by any chance talking about this book?

Nope. There are very few people who understand the entire book, and majority of the authors don't write in English, so there is very little chance that such a book gets translated.

Here's some reading list for you. I have a copy of Keller in reprints (as well as electronic subscription) so I didn't include in this shot. The top book is the Japanese book I'm talking about. You could ask the head office of Society of Photographic Science and Technology of Japan, located in Tokyo Polytechnic University (Tokyo kougei university) but I doubt they have anything about this book in English.

The second one from the top is Photographic Sensitivity written by Tani. He recently published another book. He is very smart guy and has deep insight and broad areas of specialty. His books are usually very difficult to comprehend but it is very rewarding to digest one paragraph at a time. Tani was head of Fuji's research lab for years, and also a part of the management team.

Mitchell’s Photographic Science is a more accessible, upper level college science elective level treatment of photographic sensitivity and samples science from photography. Mitchell himself is also a research physicist who was active in theories of photographic sensitivity.

The next two volumes are Haist. These are reprinted versions, purchased directly from Grant Haist.

The second from bottom is James 4th edition. Not an easy book to understand, but it is like a giant collection of extensive review papers. If you don’t understand relevant chapters of this book, you are a fake photographic engineer. I think it is fair to say that.

The bottom one is the last edition of Neblette’s Handbook, edited byb Sturge. Many best scientists and engineers from Eastman Kodak, Polaroid, 3M, Du Pont de nemours, and others contributed to various editions of Neblette’s. Some of the earlier ones are of historic significance but this last edition is pretty good as a somewhat current knowledge of this broad and deeply integrated field.

Don’t jump on difficult books first. I guess that helps you realize how little you know, if that motivates you to study hard. But I think most people find Keller to be a good “textbook” to start with.
 

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Ryuji

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The author of the book you linked, Shinsaku Fujita, is an organic chemist.

His home page:
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albada

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Does the choice of alkali have much effect on activity if pH is the same?

I modified my half-and-double developer ((there was a url link here which no longer exists)) to use potassium sulfite+TEA instead of sodium sulfite+sodium metaborate. With the same pH, I get much higher activity with the PS+TEA brew. Any idea why? To get comparable density, I had to reduce the phenidone by 40%.

Also, in The Film Developing Cookbook, Anchell and Troop state "Potassium sulfite is occasionally used in highly concentrated formulas such as Rodinal. We do not recommend its use elsewhere, except where it is unavoidable." Why are they opposed to it? I'm using the 45% solution of potassium sulfite sold by PhotoFormulary, and it works fine and is convenient. I see nothing against it.

Mark Overton
 

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Mark;

K2SO3 should equal Na2SO3 in solvent effects. It should also buffer pretty much the same so have you checked the pH of the working solution?

As for Potassium salts, the problem is that they exhaust the fixer more rapidly if one has a sloppy work flow. Too much K ion in a fix will poison it! Bill and I have discussed it and with a good running water rinse or a good fresh stop after the developer or using a one shot fix, there should be no problem.

Of course, K salts are more expensive in the US.

PE
 
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albada

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Mark;

K2SO3 should equal Na2SO3 in solvent effects. It should also buffer pretty much the same so have you checked the pH of the working solution?

As for Potassium salts, the problem is that they exhaust the fixer more rapidly if one has a sloppy work flow. Too much K ion in a fix will poison it! Bill and I have discussed it and with a good running water rinse or a good fresh stop after the developer or using a one shot fix, there should be no problem.

Of course, K salts are more expensive in the US.

PE

Ron, thanks for the info. The help is always appreciated!
The pH of this developer was 8.04 before and after I changed the alkalis.
The result of the latest fine tuning of this formula is (for one liter):


Potassium sulfite ............ 100 ml of 45% solution
Ascorbic acid .................. 4.5 g
TEA ................................ 1.7 g (yes, grams)
Phenidone ...................... 0.034 g

Target pH = 8.0. My measured pH = 8.02.
Develop TMY-2 for 13 minutes at 20C.

This formula is where I'm at now. Once I get this fine tuned, I'll switch to Dimezone. Any suggestions for improvements on this approach?
BTW, after developing a 1.5 frame-long strip in 100 ml of that formula, the developer was a little yellow. Its pH was 8.04 afterwards (8.02 before). Might this indicate a capacity-problem? I'm concerned that 250 ml might not have enough capacity for a 36-shot roll.

Mark Overton
 
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Ryuji

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after developing a 1.5 frame-long strip in 100 ml of that formula, the developer was a little yellow. Its pH was 8.04 afterwards (8.02 before). Might this indicate a capacity-problem? I'm concerned that 250 ml might not have enough capacity for a 36-shot roll.

Yellow color means ascorbate is oxidized.

Clear solution means ascorbate may or may not be oxidized. Generally speaking, in most plausible reaction pathways, rapid oxidation of ascorbate catalyzed by iron does not always discolor. It more often doesn't.

Triethanolamine does have a mild development accelerating effect other than the pH factor. This effect is even greater with diethanolamine, ethanolamine, methylethanolamine and dimethylethaolamine.
 
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albada

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Two surprises with potassium sulfite (used instead of sodium sulfite):

  1. It works unusually cleanly when combined with TEA. Potassium sulfite + TEA appears to act as a mild restrainer, giving low fog even when overdeveloped. The toe seems to be flatter, so there's a slight loss of darkest shadow-detail (and probably speed). I did not get this restraining effect when these alkalis were used separately.
  2. As I mentioned before, PS accelerates development of phenidone+ascorbic and dimezoneS+ascorbic. After some fine-tuning, I find I need about a third less developer to get the same activity.
There's not much of a cost-difference between potassium sulfite and sodium sulfite. I took PhotoFormulary's prices for 1 liter and 1 pound, and got 20 cents versus 16 cents per roll. PS is more convenient, since it comes in a concentrate, but don't forget PE's warning about washing it out in the stop-bath to avoid killing the fixer.

Ryuji: I tried developing again using the light yellow developer, and it worked fine, keeping most (all?) of its activity. But after the 2nd strip, the developer was a light orange! I hold the film-strip in the graduate using a non-stainless steel clip; might iron from that be upsetting the chemistry?

Mark Overton
 

Ryuji

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  1. It works unusually cleanly when combined with TEA. Potassium sulfite + TEA appears to act as a mild restrainer, giving low fog even when overdeveloped. The toe seems to be flatter, so there's a slight loss of darkest shadow-detail (and probably speed). I did not get this restraining effect when these alkalis were used separately.
  2. As I mentioned before, PS accelerates development of phenidone+ascorbic and dimezoneS+ascorbic. After some fine-tuning, I find I need about a third less developer to get the same activity.

I’m not convinced. What you described does not go well with existing knowledge in photographic chemistry. If you are going to assert as you did, I would like to see more details, including statistics of your measurements.

There’s not much of a cost-difference between potassium sulfite and sodium sulfite. I took PhotoFormulary's prices for 1 liter and 1 pound, and got 20 cents versus 16 cents per roll. PS is more convenient, since it comes in a concentrate, but don't forget PE's warning about washing it out in the stop-bath to avoid killing the fixer.

Potassium salt is less environmentally friendly; it requires more energy to obtain, and then ship. Potassium is also less abundant resource compared to sodium. What you stated above simply suggest to me that Formulary is making less margin with potassium sulfite.

Ryuji: I tried developing again using the light yellow developer, and it worked fine, keeping most (all?) of its activity. But after the 2nd strip, the developer was a light orange! I hold the film-strip in the graduate using a non-stainless steel clip; might iron from that be upsetting the chemistry?

First of all, how do you know the color comes from the oxidation and not from the sensitizing and antihalation dyes from the film?

My developers have powerful stabilizing agent to protect ascorbate from iron catalyzed oxidation, so the worst I’ve seen in actual and reasonable use situation is very pale yellow. I use stainless beaker to adjust the temperature quickly in a water bath, and I also use stainless steel reel and tank for 35mm (Paterson tank for 120/220).

In my past experimentation, if you use a stainless beaker or tank, the iron used in the vessel/apparatus does go in to the solution, although in a tiny amount, and I could easily detect that difference chemically.
 

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Incidentally, in the past, it was said that potassium thiosulfate is a poor fixing agent compared to sodium, and this is probably why a rumor of potassium salt in fix ruins the bath. In reality, there’s no reason to go beyond ammonium or sodium salt anyway, and I could not detect change in clearing time by adding a reasonable amount of potassium sulfite to an ammonium thiosulfate fixing bath. I’m not going to say the rumor was incorrect, but I might say irrelevant.
 
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albada

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Incidentally, in the past, it was said that potassium thiosulfate is a poor fixing agent compared to sodium, and this is probably why a rumor of potassium salt in fix ruins the bath. In reality, there’s no reason to go beyond ammonium or sodium salt anyway, and I could not detect change in clearing time by adding a reasonable amount of potassium sulfite to an ammonium thiosulfate fixing bath. I’m not going to say the rumor was incorrect, but I might say irrelevant.

I did some clearing time experiments on samples of my fixer:


Straight fixer: cleared in 3 minutes.
Fixer with .2 ml potassium sulfite concentrate added to 10 ml: cleared in 2.75 minutes.
Above solution after sitting overnight (testing for slow death): cleared in 2.75 minutes.

Conclusion: Potassium sulfite not only does not harm my fixer, it benefits it (reduces clearing time). BTW, my fixer was made by Zone VI Studios, which AFAIK uses sodium thiosulfate. It specifies 5-8 minutes for fixation, so it's not a rapid-type fixer. OTOH, potassium sulfite might destroy other types of fixers, so don't go pouring K2SO3 into your fixer just yet. :smile:

Mark Overton
 
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albada

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I finally got finer grain than XTOL! By a small margin, but finer when carefully compared in a pair of 22X loupes. I only tested it with TMY-2, and this one-liter formula is merely a baseline for further work:


Potassium Sulfite, 45% solution ... 80 ml
Ascorbic acid ........................... 4.5 g
TEA ....................................... 2.7 g (yes, grams; = 2.4 ml)
Dimezone S ............................. 0.067 g

Target pH=8.0. Starting dev-time is twice undiluted-XTOL's time.

On TMY-2, the grain is slightly less clumpy and less stringy than XTOL's, and thus appears more like fine sand in my 22X loupes. Grain also appears slightly finer than XTOL in monotone areas. As mentioned earlier, the toe is slightly lower than XTOL, but the difference is small enough that most people probably wouldn't notice. I'll use this formula as a baseline for more experiments, including (1) using sodium sulfite instead because that's what most people have, (2) reducing sulfite and boosting TEA to reduce chemistry, (3) making a PG-based concentrate out of it, (4) general fine tuning and testing, and (5) other films.

Here are full-resolution crops of neg-scans of TMY-2 in XTOL (left) and this test-developer (right):

5-00-XTOL-FocusVCrop.jpg - 5-26-DimezoneFocusVCrop.jpg

In both cases, the scanner was manually focused on the "V". Although the scanner can't pick up individual grains, you can see there's less noise in the second scan due to finer grain. Also, I want to take some grain-photos through a microscope and post them, but it'll take some time to get a microscope-setup working.

Mark Overton
 
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Nice work.

How are you using Xtol? Stock? 1:1, or even more dilute? Replenished?

Do you print these to see what they do when projected?

I finally got finer grain than XTOL! By a small margin, but finer when carefully compared in a pair of 22X loupes. I only tested it with TMY-2, and this one-liter formula is merely a baseline for further work:

Potassium Sulfite, 45% solution ... 80 ml
Ascorbic acid ........................... 4.5 g
TEA ....................................... 2.7 g (yes, grams; = 2.4 ml)
Dimezone S ............................. 0.067 g

Target pH=8.0. Starting dev-time is twice undiluted-XTOL's time.

On TMY-2, the grain is slightly less clumpy and less stringy than XTOL's, and thus appears more like fine sand in my 22X loupes. Grain also appears slightly finer than XTOL in monotone areas. As mentioned earlier, the toe is slightly lower than XTOL, but the difference is small enough that most people probably wouldn't notice. I'll use this formula as a baseline for more experiments, including (1) using sodium sulfite instead because that's what most people have, (2) reducing sulfite and boosting TEA to reduce chemistry, (3) making a PG-based concentrate out of it, (4) general fine tuning and testing, and (5) other films.

Here are full-resolution crops of neg-scans of TMY-2 in XTOL (left) and this test-developer (right):

45005-improved-version-ds-10-ryuji-suzuki-5-00-xtol-focusvcrop.jpg.att
-
45006-improved-version-ds-10-ryuji-suzuki-5-26-dimezonefocusvcrop.jpg.att


In both cases, the scanner was manually focused on the "V". Although the scanner can't pick up individual grains, you can see there's less noise in the second scan due to finer grain. Also, I want to take some grain-photos through a microscope and post them, but it'll take some time to get a microscope-setup working.

Mark Overton
 

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Very nice work.

My comments about Potassium in the fixer come from comments in Haist and in Mees. I have not personally tested this myself.

The work comes from their comparisons of different salts such as K, Na, NH3 and Ca in fixers and the presumption in some of the literature was that the larger cations made the Silver / Hypo complex more difficult to diffuse.

In fact, there are recent patents that claim that small amounts of Potassium salts actually speed fixing but there is no explanation. My own patent on film Blixes notes an increase of Blix speed with KI present which is counter intuitive.

PE
 
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albada

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Nice work.
How are you using Xtol? Stock? 1:1, or even more dilute? Replenished?
Do you print these to see what they do when projected?

Thomas,
I'm using Xtol stock (1+0) one-shot, so that's 6.5 minutes at 20C. I wanted XTOL to show off the finest grain it could. Everything is done at 20C with identically exposed strips.

No printing yet. I have a list of changes to that formula I want to try -- substituting chemicals, changing quantities, dropping pH more, etc. I'd like to see if I can do better, or perhaps do just as well and use less chemistry. In addition, the experiments provide a "feel for the environment" -- an intuition of what effects changes will have. But it takes patience: Once cycle of mix developer/temper bath/dev strip/fix/clean up takes me about an hour. I'm careful and accurate, which is good for repeatability, but such care eats time.

I want to get a densitometer. I'm tired of matching densities by eye, and a densitometer will let me create absolute and relative density-curves, which will clearly reveal loss/gain of speed, contrast/CI, highlight-compression, and anything else relating to tone-levels.

As an aside, I notice that the test-developer image (2nd image) is a bit darker than XTOL's image. Dense areas of the neg's had matching densities, judging by eye through two pieces of paper with a hole punched in each. The difference might be due to auto-exposure in the scanner, which I can't control.

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Mark,

Thanks for the explanation.

I find that I get finer grain from Xtol by using it replenished. It's also sharper and has some restraining action in the highlights due to the bromide byproducts (great for portraits). You do lose about 1/3-1/2 stop or so, so the tonality changes somewhat.

I'm impressed with your results. Keep up the great work.

- Thomas


Thomas,
I'm using Xtol stock (1+0) one-shot, so that's 6.5 minutes at 20C. I wanted XTOL to show off the finest grain it could. Everything is done at 20C with identically exposed strips.

No printing yet. I have a list of changes to that formula I want to try -- substituting chemicals, changing quantities, dropping pH more, etc. I'd like to see if I can do better, or perhaps do just as well and use less chemistry. In addition, the experiments provide a "feel for the environment" -- an intuition of what effects changes will have. But it takes patience: Once cycle of mix developer/temper bath/dev strip/fix/clean up takes me about an hour. I'm careful and accurate, which is good for repeatability, but such care eats time.

I want to get a densitometer. I'm tired of matching densities by eye, and a densitometer will let me create absolute and relative density-curves, which will clearly reveal loss/gain of speed, contrast/CI, highlight-compression, and anything else relating to tone-levels.

As an aside, I notice that the test-developer image (2nd image) is a bit darker than XTOL's image. Dense areas of the neg's had matching densities, judging by eye through two pieces of paper with a hole punched in each. The difference might be due to auto-exposure in the scanner, which I can't control.

Mark Overton
 

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Just FYI, the Formulary in MT have excellent densitometers for sale. They are unlisted. You can get them with a special order. I have one and it works for both reflection and transmission.

PE
 
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albada

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Just FYI, the Formulary in MT have excellent densitometers for sale. They are unlisted. You can get them with a special order. I have one and it works for both reflection and transmission. PE

Can you recommend an economical model? Michael R asked for curves, which I'm also aching to see, and those start with a densitometer.
I'm tempted to hack a 2-3 mm diameter aperture onto an old light-meter to be placed on the neg on the light-table. Perhaps by drilling a hole into its diffusion-dome and painting the dome black.
Do you know if the Formulary sells Stouffer wedges? Or does one buy those directly from Stouffer?

Michael: Those were 1-second exposures, and the tripod was on carpet, so there's a chance there's a bit of motion-blur in there. I'll have to dev a couple more strips and keep an eye out for sharpness.

Mark
 
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Not sure where you're located, but I'd be glad to read the densities for you if you need help with this. If you want to buy one, used models can sometimes be had for relatively low prices on eBay etc. I bought my Heiland from Versalab (it does both transmission and reflection) and have found it to be both reliable and easy to use. It was expensive though. I was going through a phase where I did massive amounts of film/developer/ZS testing so I felt it was worth the investment at the time. Now, not so sure! :smile: Regarding step wedges, I bought mine directly from Stouffer some years ago. Not sure who else you can buy them from.

Michael, thanks for the offer, but my initial use will be to adjust chemical-quantities and/or dev-times so that test-strips will match the strip produced by XTOL. That means intermittent use of the meter, which I guess means it needs to be here in southern California. Once a formula is looking solid, I'll do some sensitometry with it. For mere density-matching, I might just use a hacked light-meter until I get something better.

PE and Michael: Thanks for the tips on where to get Stouffer wedges.

Mark Overton
 
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