Diafine: substitute Metol for Hydroquinone ?

[Ken Lee]

I found the following formula for Diafine, and I have all the ingredients except Hydroquinone.

Could we substitute Metol for Hydroquinone ? If so, how much please ?

Thanks in advance :)

Solution A:
Water at 125F/52C 750 ml
Sodium sulfite, anhydrous 35 grams
Hydroquinone 6 grams
Phenidone 0.2 grams
Sodium bisulfite 6 grams
Room temperature water to make 1.0 liter

Solution B:
Water at 125F/52C 750 ml
Sodium sulfite 65 grams
Borax 20 grams
Cold water to make 1.0 liter

[Erik Larsen]

I don't believe so, but I think you could sub the phenidone with metol:)
Not very helpful, sorry.

[Gem Singer]

Ken,

Hydroquinone is a high contrast developing agent, like Pyro

Metol is a low contrast developing agent, like Phenidone.

Using Metol + Phenidone in that formula will probably result in a very low contrast negative.

[Sevo]

The real problem is that the Hydrochinone in MQ developers interacts with the Metol type other developing agent (in your case, Phenidone) - I am not aware of a Metol/Phenidone developer, as the Metol in that mix would be redundant.

[sanking]

I found the following formula for Diafine, and I have all the ingredients except Hydroquinone.

Could we substitute Metol for Hydroquinone ? If so, how much please ?



Ken,

Substitution of metol for hydroquinone would result in a very low contrast developer, barring some type of unexpected synergy between metol and phenidone.

You may be able to substitute pyrocatechin for hydroquinone in this formula since these reducers are somewhat similar in contrast and working pH, and both should be synergistic with phenidone.

Sandy

[Sevo]

Ken,

Substitution of metol for hydroquinone would result in a very low contrast developer, barring some type of unexpected synergy between metol and phenidone.


Phenidone is self-inhibiting (hence there are no solitary Phenidone developers I am aware of) and that will probably extend to Metol.

[Gem Singer]

Sevo,

Look up POTA Developer (the "P" stands for Phenidone). Very low contrast developer.

It was used for negatives that were exposed to the bright flash of an atomic bomb explosion.

D-23 is a developer that only contains Metol as it's developing agent.

[Leigh]

Why not just buy Diafine?

Mixing our own rather than buying commercial is a great way to put companies out of business.

- Leigh

[Sevo]

Sevo,

Look up POTA Developer (the "P" stands for Phenidone). Very low contrast developer.

It was used for negatives that were exposed to the bright flash of an atomic bomb explosion.


You are of course right - I've even used it, to tame Technical Pan and other ultra-high contrast process films.



D-23 is a developer that only contains Metol as it's developing agent.

Metol developers aren't (or weren't) that rare - most makers used to have one, often described as "softer paper developer" in their recipes. But Metol is nowhere as self-inhibiting as Phenidone (while the latter seems to inhibit Metol as well).

[Ken Lee]

For the record, I saw Sart S's still-life photos (http://www.largeformatphotography.info/forum/showthread.php?85162-Still-Life-Images-2012&p=961311&viewfull=1#post961311) today, and it reawakened my interest in divided developers.

Divided Pyrocat HDC is great, but I like to experiment from time to time, so thought I'd give Diafine (or something like it) a try.

[Ken Lee]

Why not just buy Diafine?

Mixing our own rather than buying commercial is a great way to put companies out of business.

- Leigh

I have taken your good advice and purchased some Diafine.

[evan clarke]

Problem is, these companies are going out of business regardless of your $20 purchase. Make your own chems..

[Leigh]

The companies are going out of business because so many people are making their own chems.

- Leigh

[sanking]

The companies are going out of business because so many people are making their own chems.

- Leigh

Photographers have been mixing their own developers since the beginning of photography in the 19th century. I seriously doubt there is any correlation between people mixing their own chemistry and companies going out of business. The great majority of photographers will never mix their own as long as commercial developers are available.

Companies that deal in film and photographic chemicals are going out of business because people are switching to digital.

Sandy

[Bill_1856]

It's cheap -- just buy a can already prepared.

[David Karp]

Ken,

I have seen that formula before, but I have some doubts that it is really Diafine. I recall googling the MSDS sheet for Diafine and found that Part B uses sodium carbonate. I assume that is the accelerator, not borax.

[Ken Lee]

Ken,

I have seen that formula before, but I have some doubts that it is really Diafine. I recall googling the MSDS sheet for Diafine and found that Part B uses sodium carbonate. I assume that is the accelerator, not borax.

Thanks - another good reason to try the real formula.

To see what happens with divided development when shooting under overcast light, I made some tests this morning with Divided Pyrocat HDC. It was possible to expose for the deep shadows so that they didn't look inky black, without blowing the reflections of the sky.

A certain sense of analog smoothness comes with this process: it's really appealing. Perhaps because the film is developed only at the surface, it makes 4x5 feel like 5x7.


http://www.kennethleegallery.com/images/forum/img007da.jpg
Ivy, 2012
Sinar P, 210mm Macro Sironar N
4x5 TMY, Divided Pyrocat HDC

[David Karp]

Beautiful.

I have some negatives to develop soon. When I do that I am going to try to do some tests with divided Pyrocat MC at the same time. I am going on a quick family trip to Yosemite early in January, and plan to take a LF camera with me. My past experience has been that divided developers are great for photographing snow.

[BetterSense]

It's cheap -- just buy a can already prepared.

Everywhere I've looked, Diafine is now >$40 per gallon. That's not what I call "cheap".

[Ken Lee]

One thing to remember (at least with Divided Pyrocat) is to add several drops per liter of PhotoFlo to Solution A, to prevent streaking or uneven development. It works miracles.

Another thing: Diafine may be different, but with this formula and TMY, the film grain is just barely discernible with a 15x loupe. I presume that with even finer grain film it would be - to quote the vernacular - zip.

[Ken Lee]

Everywhere I've looked, Diafine is now >$40 per gallon. That's not what I call "cheap".

Reportedly, people use the stuff for years. They just keep topping off the solution.

[Nathan Potter]

Ken, I use the commercial Diafine a lot and would recommend what Leigh said; buy the commercial product.

For me the advantage is the long tonal range possible, but even more important is the fine grain with nice acutance for silver printing. I tend to want the grain for certain types of prints where I use a very hard light source with significant enlargement.

Sandy did a handy evaluation of Diafine a few years back and it appeared in VC - thanks for that Sandy. That got me interested in it for use with higher contrast scenes. I should do more investigation and calibration on some of the variables, but just have not gotten to it.

Nate Potter, Austin TX.

[BetterSense]

My batch has been going since 2009, but I'm down to about 800mL of the original gallon. I'm still having a hard time getting myself to spend $45 on a new gallon.

Grain and diafine is a weird thing. I have some 35mm Tri-X negatives that have exaggerated popcorn-size grain. I have other negatives from the same camera, same film, that make an 11x14 print with barely visible grain.

[Ken Lee]

I paid $34.95 from Amazon, which was actually an order from Adorama.

[JMB]

The companies are going out of business because so many people are making their own chems.

- Leigh

The chemical mix is an exciting part of the creative process. It makes sense to me that many artists would not want to automatically turn this part of photograph making over to third parties. And there is frequently a bit of tension between what a company has to do (what to put in and what to leave out) for commercial instead of aesthetic reasons.

To be sure if my two choices are (1) always buy commercial formulas so that some company can stay in business, or (2) always mix my own formulas because no company is available to make formulas; then I think option (2) is best. The matter, in any case, does not break down this way. And of course there is no reason to simply ignore what a commercial enterprise may have been able to accomplish. Still, at least for me, it is hard to resist the impulse to find my own path.

[bob carnie]

Agree with Gem
I use metol only for soft developers so this makes sense.

Ken,

Hydroquinone is a high contrast developing agent, like Pyro

Metol is a low contrast developing agent, like Phenidone.

Using Metol + Phenidone in that formula will probably result in a very low contrast negative.

[Jim Noel]

Phenidone is self-inhibiting (hence there are no solitary Phenidone developers I am aware of) and that will probably extend to Metol.
It does not extend to Metol. D-23 is a very old and still popular Metol only developer. There is not even an accelerator, only sulfite, a preservative.

[Sevo]

It does not extend to Metol. D-23 is a very old and still popular Metol only developer. There is not even an accelerator, only sulfite, a preservative.

I know - but I did not mean that. It rather looks as if the Phenidone oxidation by-products also inhibit Metol.

[Mark MacKenzie]

Ken, I hope you can keep posting your experience with Diafine. I am very interested in your approach and testing. Thanks!

[Ken Lee]

Thanks - I will do that.

[Kevin J. Kolosky]

The "IVY"2012 image is very nice.

What would you say, in terms of stops, the Pyrocat developer had in terms of contraction. You say that you were able to preserve the borderline blacks without blowing out the highlights. In using a more "normal" developer how many stops of contraction do you feel you would have had to have used instead to get an equivalent image.

[Ken Lee]

That's a a good question, and shows that my "test" is a bit shabby.

Sandy will know best of course, but my understanding is that short development times - as opposed to heavyweight compensating methods like water bath and stand development - work at the expense of film speed, and are usually limited to N-1 or N-2. Pyrocat developers give good compensation when used normally - but I'm not sure they are dramatically different from other formulas when it comes to short development times: they are probably limited to N-1 or N-2.

In my experience they give staggering contraction - without loss of film speed and with no special handling required - when used divided.

[sanking]

The down side of short development times for compensation of high subject contrast is indeed reduced effective film speed, and it is true with Pyrocat as well as other developers. On the other hand, stand or semi-stand development will likely result in an increase in effective film speed, but the down side is the possibility of streaking from reduced agitation.

Diafine, and Pyrocat, when used as two bath developers, are capable of extreme compensation, and as Ken notes, with no loss of film speed and no need for special handling. Regardless of the contrast of the scene you simply make sure to expose for the deepest shadows where you want texture or detail, then develop the film in a two bath formula like Diafine or Pyrocat. The result should be a negative with good shadow detail, a linear curve, and highlights that are well within limits for scanning with a consumer type scanner like the V700. This is about as close to a silver bullet in film developing as I have found.

Should note that some of the other two-bath developers, say divided D23, divided D76, Stoeckler, etc. do *not* work like Diafine and Pyrocat. With these developers there is some development in Solution A, and the final result in terms of contrast varies with time of development. With Diafine and two bath Pyrocat there is no development at all in Solution A, then development is almost instantaneous when it goes into Solution B. And increased time in Solution B does not increase contrast because once the reducer is gone that the film absorbs in Solution A development is over

Sandy

[Ken Lee]

I just developed some TMY in Diafine (75 degrees for 5 minutes in each bath) observing the with process my infra red viewing device.

I was surprised to see some development taking place while the negatives were in Solution A.

Perhaps I inadvertently contaminated the chemistry. Has anyone else ever watched what happens with Diafine ?

[Sevo]

I was surprised to see some development taking place while the negatives were in Solution A.


It would be rather odd if there were none - as far as I understand it, A contains the main active component, and even if it does not do much, it must do something before self-inhibition strikes.

[sanking]

I just developed some TMY (75 degrees for 5 minutes in each bath) observing the with process my infra red viewing device.

I was surprised to see some development taking place while the negatives were in Solution A.

Perhaps I inadvertently contaminated the chemistry. Has anyone else ever watched what happens with Diafine ?

That is somewhat surprising to me as well. I never watched the process of development but I did run a test once where I just fixed out the negative after Solution A and there was no visible image, or perhaps it was so faint I missed it. Of course, if there is any sodium sulfite in Solution A, which there may be as a preservative, it would provide some energy for the hydroquinone.

Sandy

[sanking]

Ken,

Just curious to know if you have watched the process of development using two-bath Pyrocat? I am almost certain that the pH of a working solution would be too low to activate the pyrocatechin but I would sure be interested to know for sure.

Sandy

[Ken Lee]

I have watched the process with Divided Pyrocat many times, and I have never seen any development in solution A.

[Ken Lee]

http://www.kennethleegallery.com/images/forum/diafine200.jpg
Film Test, 2012
Kodak TMY, Diafine

My tests are not scientific: only empirical.

I made this photo in clear sunshine. The white items fell on Zone VIII and higher, but Diafine controlled them quite nicely: I had to add contrast. It's very easy to distinguish between white plastic and the reflections of the sun on it. I also like the continuous transitions on the plastic bottles.

Interpolating between ISO 200 and 400, with TMY I get a film speed of around 250 or 300, which is what I get with other developers (D-23, Pyrocat HDC, Divided Pyrocat HDC). Whatever claims the Diafine manufacturer makes for higher speed, I haven't attained it with this combination.

The grain is very fine, almost invisible, but my Divided Pyrocat negatives exhibit slightly more invisible grain. The difference only shows up under my 15x loupe. I presume that smoothness comes from the staining/tanning effect of pyro.

My next test is re-using the developer: re-use being one of the core value propositions of the formula.

[Ken Lee]

http://www.kennethleegallery.com/images/forum/img013tc.jpg
Spectacles, 2012
Sinar P, 210mm Macro Sironar
4x5 TMY, Diafine

This was lit by window light. Again, there has been quite a bit of compensation: the reflections of the sky would ordinarily be pure white. I had to add some contrast. Pretty slick. And the developer has been re-used 1 day later.

[Ken Lee]

http://www.kennethleegallery.com/images/forum/img012sv.jpg
Storage Area, 2012
Sinar P, 210mm Macro Sironar
4x5 TMY, Diafine

This was a one-minute exposure, lit entirely by natural light. Exposing for the deepest shadows, there is still plenty of detail looking out the window. I'm dumb-struck.

It was dark enough that the light meter gave readings of 0 for most of the scene, so I placed the wall on Zone IV and let everything else go where it wanted.

[Mark MacKenzie]

Wow, very interesting. Cloudy skies, right? Thats not harsh sun out the window is it?

These are scans of the neg? How will they print? Last question, how does it appeal to your artistic sensibilities?
Thanks for sharing, Ken.

[Ken Lee]

Wow, very interesting. Cloudy skies, right? Thats not harsh sun out the window is it?

These are scans of the neg? How will they print? Last question, how does it appeal to your artistic sensibilities?
Thanks for sharing, Ken.

Yes, the skies were cloudy, but easily beyond the reach of normal developers. I have added contrast to the image: there is actually much more detail looking out the window, but I tossed some of it to make the print in a hurry. For me, the aesthetic content is largely in the rendition of the other areas.

These are scans of the negative, and since I print with inkjet, they look basically the same, except much larger of course.

See this thread on Divided Pyrocat (http://www.largeformatphotography.info/forum/showthread.php?52913-Anybody-using-Pyrocat-HD-or-MC-as-a-Compensating-Developer) for many more photos of similar nature, some taken indoors looking out upon scenes lit by bright sunshine.

I really like the look, which to my limited perception makes 4x5 seem more like 8x10 in terms of smoothness and subtlety. It's easier to judge with larger images. I will post a detail section of the bicycle photo later when I get a moment.

[Ken Lee]

Here is a link (http://www.kenleegallery.com/html/tech/bikewindow.html) to a larger copy of the image.

This is subjective of course, but there is a kind of analog ease about the way the tones are handled, as though there were no strain. It's a look that I associate more with contact prints from large negatives, or with carefully lit studio setups where the subject brightness range has been carefully mapped to fit the medium.

Here, no such precautions were taken: there are some white items near the window on the right of the image, and they should have been pure white, off the scale. The photo looks like all the lighting was carefully planned, but it wasn't. It was actually crummy lighting.

[Mark MacKenzie]

So Ken, if I am understanding this, if you shot this say at 30 secs instead of a minute, or say at 7 secs, a three stop difference, the shadows would lose detail but in the highlights detail would practically stay the same? Do you think the wall would go down 3 zones? I am anxious to try it.

BTW, I love my three speed Raleigh. I have a 74 Tourist.

[Ken Lee]

So Ken, if I am understanding this, if you shot this say at 30 secs instead of a minute, or say at 7 secs, a three stop difference, the shadows would lose detail but in the highlights detail would practically stay the same? Do you think the wall would go down 3 zones? I am anxious to try it.

Yes - this comes from Sandy's research and writings, and others before him.

With truly divided developers, we expose for the shadows and don't give a hoot about the highlights until after development (if at all). As he has discussed, it's an ideal approach for roll film or other similar situations, especially since divided developers give such fine grain.

What I'm considering (and I'm certainly not the first) is to follow this approach all the time, since I rarely make darkroom prints. With a proper digital workflow, there's no limit to the contrast we can add to scanned negatives, and there seems to be an even more compelling benefit than convenience: the images can often look nicer.

Apparently Diafine was developed with Tri-X in mind, and the manufacturer claims a high effective film speed with it. I will probably shoot a test roll if I have one lying around, to investigate the actual film speed and grain. Perhaps others here have already done so, and can share their experiences.

[sanking]

Apparently Diafine was developed with Tri-X in mind, and the manufacturer claims a high effective film speed with it. I will probably shoot a test roll if I have one lying around, to investigate the actual film speed and grain. Perhaps others here have already done so, and can share their experiences.

TRI-X developed in D76 and most other developers typically has a long toe and flaring shoulder. If developed in Diafine, TRI-X has a very linear curve, with short toe and shoulder. In other words the compensation is spread over the entire curve, not just the shoulder as we see with some compensating type developers. This results in an apparent increase in film speed of about 1/2 to 2/3 stops compared to TRI-X developed in D76. However, if you value shadow detail in Zone II it would still be best to expose TRI-X at an EI of 250-300.

There are lots of myths about Diafine. For example, some claim that a pre-soak and/or constant agitation does not work with Diafine. Actually it works fine. The reason the manufacturer does not recommend these procedures is because they would change the average contrast of a given film at the recommended times.

Divided developers work this way. Traditional one-bath developers contain a reducing agent(s) and an alkaline accelerator. In two-bath developers the reducer is in Solution A, and the alkaline accelerator is in Solution B. The film is first placed in Solution A, where it soaks up the reducer, but no image (or a very faint one) is formed. The film is then transferred to Solution B, which contains the accelerator, and the image is formed. The contrast of the negative is limited by how much of the reducer the film was able to soak up during the first bath, so the highlights develop first and then stop because the developer exhausts in this area, but the shadows continue to develop.

So what determines how much reducer the emulsion can soak up in Solution A. There are three factors, 1 ) the emulsion, 2) temperature of Solution A, and 3) amount of agitation. Taken together, a film with a soft emulsion in a very warm solution with constant agitation will absorb more reducer than a film with a hard emulsion in a cool solution with little or no agitation. The more reducer it absorbs, the higher will be the final contrast. Final contrast is pretty much determined before the film ever hits Solution B.

So you can use Diafine with constant agitation if you like. You will get a bit more contrast than with the recommended development procedures of the manufacturer, but the negatives will be fine otherwise.

Sandy

[Ken Lee]

Excellent - Thank you !

[patrickjames]

I just saw this thread and maybe can answer your original question. I am not a chemistry expert though, so don't quote me.

If I remember correctly, Hydroquinone and Phenidone create a super-additive pair and a regenerative one as well, although I can't remember if the HQ regenerates the PH or visa verso. This would explain the long shelf life of Diafine and why it works so well as a divided developer.

I am not very fond of two bath development because of the possible problems. I did make up one that combined Metol and Glycin a couple of years ago that I thought was pretty good, or at least I liked it more than Thornton's. I haven't bought Glycin since though. I will probably look at it again when I get some Glycin. I have always thought Pyrocat was good enough with compensation to not have to use it divided, although I have to admit I have never tried it divided.

[Cor]

Ken,

Intriguing results ! Would you mind elaborating a bit how you exactly work with Diafine. How do you process your film, in those Tupperware (?) boxes you mentioned ?
What temp and time and agitation in each bath ?

I'am currently playing a bit with Fomapan 100 in 4*5 and that film quite easily picks up contrast, so perhaps Diafine would be an option.

One more question: under "normal" light conditions (say 5 stops) will applying Diafine not result in (too) flat a negative ?

Thanks & best,

Cor

[Ken Lee]

Intriguing results ! Would you mind elaborating a bit how you exactly work with Diafine. How do you process your film, in those Tupperware (?) boxes you mentioned ?
What temp and time and agitation in each bath ?

One more question: under "normal" light conditions (say 5 stops) will applying Diafine not result in (too) flat a negative ?


I use the plastic containers the same way we would use trays. They are trays, just very deep and very small. I repeatedly pull the bottom sheet out and place it on the top, then push it down. Nothing special. With this method I routinely develop up to 20 sheets at a time, in 2 liters of developer.

Click here (http://www.kenleegallery.com/pdf/Diafine.pdf) to download a copy of the Diafine instruction sheet. For my tests, I used 75 degrees F/ 24 degrees Celsius.

Watching the results with an infra red viewing device, I notice that after a minute or two at most, time has no effect - just as the manufacturers have stated. The process is very fast. I presume that the manufacturer recommends 3 minutes because they also recommend minimal agitation, and they want to make sure that development is even across the negative.

Sandy has explained how to control the contrast of negatives. See post 47 (http://www.largeformatphotography.info/forum/showthread.php?97694-Diafine-substitute-Metol-for-Hydroquinone&p=968173&viewfull=1#post968173) below in this thread. I haven't made any darkroom prints with Diafine, but presume that the contrast index is high enough that number 4 paper could handle it if necessary. Sandy and others will know best.

[Cor]

Thanks, Ken !

Best,

Cor

[marfa boomboom tx]

concentration of "A" is a control factor.

mix the same mfg pack A into half the water, or
mix the same mfg pack A into twice the water --

these are tuning methods used back when the Dia was new.

it is left as an exercise to boomboom your own film.

[sanking]

"concentration of "A" is a control factor.
mix the same mfg pack A into half the water, or
mix the same mfg pack A into twice the water -- "

In my experiments with Diafine I found that you could get about the same contrast with rotary development as with standard procedures by diluting the Stock A solution 1 + 1 with water, keeping time of development the same.

Interestingly, many of the same considerations for controlling contrast with a two-bath developer are similar to those carbon printers use in sensitizing carbon tissue. In both types of work the only absolute is that sensitivity is ultimately controlled by the total amount of reducer or dichromate that the gelatin of the film/tissue can absorb, and the basic factors that determine absorption are: 1) concentration of the reducer/dichromate solution, 2) thickness of the gelatin, 3) length of time in the solution, and 4) temperature of the solution.

Sandy

[marfa boomboom tx]

I just developed some TMY (75 degrees for 5 minutes in each bath) observing the with process my infra red viewing device.

I was surprised to see some development taking place while the negatives were in Solution A.

Perhaps I inadvertently contaminated the chemistry. Has anyone else ever watched what happens with Diafine ?

I know that you aren't using the formula you posted, however -- if you were, then the solution is just alkaline enough to begin image formation.
sodium bisulphite is added just to stop 'that' action. small amounts of sugar (yep, the sweet stuff) were also used, but then we also could buy just Diafine part A, once upon a time.

You can also experiment with other "B" solutions.

Borax, Kodalk, &such were all used. There was a book, long lost from my memory, about divided developers. It must have contained a few dozen 'recipes' with some interesting chemistry notes about why/how the writer arrived at his conclusions.

this was when Kodak Royal-x, Tri-x, and 2475 walked the earth.

marfa, the land that water forgot

[sanking]

I know that you aren't using the formula you posted, however -- if you were, then the solution is just alkaline enough to begin image formation.
sodium bisulphite is added just to stop 'that' action. small amounts of sugar (yep, the sweet stuff) were also used, but then we also could buy just Diafine part A, once upon a time.

You can also experiment with other "B" solutions.

Borax, Kodalk, &such were all used. There was a book, long lost from my memory, about divided developers. It must have contained a few dozen 'recipes' with some interesting chemistry notes about why/how the writer arrived at his conclusions.

this was when Kodak Royal-x, Tri-x, and 2475 walked the earth.

marfa, the land that water forgot

I sure would like to have that book. Two-bath development appears to have been very popular in the hey day of the miniature camera.

BTW, I was in Marfa, Texas about ten years go, during my only visit to Big Ben National Park. Fascinating place, in spite of the lack of water. What does boomboom mean?

Sandy

[marfa boomboom tx]

I sure would like to have that book. Two-bath development appears to have been very popular in the hey day of the miniature camera.

BTW, I was in Marfa, Texas about ten years go, during my only visit to Big Ben National Park. Fascinating place, in spite of the lack of water. What does boomboom mean?

Sandy

Someone in Oxbridge ought to be able to find it. Back in that time I read BJP, and bought from English bookstores. I'd guess that it is in some used store. Split developer may be an alternate title
. Google books has been useless, as has abebooks.

boomboom is an expression from an artist's manifesto -- discussing it could lead to rancor.

But, out here, over wide spaces, there is a lot of time between words, and no room for bitter people.

[Ken Lee]

What is BJP please ?

Also, thanks for confirming that some development could take place in Solution A: I was very careful when mixing the developer. The only thing that could have contaminated it, was the tray itself: I rotate my trays and use them at random, and clean them of course.

[Richard Wasserman]

BJP—British Journal of Photography

http://www.bjp-online.com/

[David Karp]

. . . I haven't made any darkroom prints with Diafine, but presume that the contrast index is high enough that number 4 paper could handle it if necessary. Sandy and others will know best.

I have made many darkroom prints with negatives developed in Diafine, and you are right. I have found that most of my negatives print very nicely on grade 3 paper (using the VC head on my enlarger). I don't recall using more than grade 4. Living in California, and often photographing in some pretty harsh light, many of my negatives print nicely on grade 2 or 2.5.

[sanking]

What is BJP please ?

Also, thanks for confirming that some development could take place in Solution A: I was very careful when mixing the developer. The only thing that could have contaminated it, was the tray itself: I rotate my trays and use them at random, and clean them of course.

Ken,

With the developer you posted the sulfite would give a working Solution A with a pH of around 8.0. This would be high enough to cause some development of the phenidone, which of course is the low contrast component of the developer. The threshold of development for phenidone is around pH 6.0. However, it would take a very long time for any significant image formation with Solution A because the pH of the working solution would not be high enough to activate the other reducer in the solution, hydroquinone, which has a threshold of development of around pH 10.0. The hydroquinone is not activated until you place it in Solution B, in the developer you posted Borax + sulfite, which would have a much higher working pH.

In the sensitometry tests I made with Diafine, following the development recommendations of the manufacturer, there was a CI of about .50 with all of the films tested, which should be about right for making silver gelatin prints in the darkroom with a condenser type enlarger with a Grade 2 or 2.5 paper or with VC paper with an equivalent filter, assuming the film was exposed in conditions of average contrast.

Sandy

[David Karp]

Thanks for this confirmation Sandy. That would match up exactly with my experience using a diffusion enlarger. I know I have mentioned this before, but before you started working with divided Pyrocat and your article in VC Magazine, people used to tell me I was crazy, and that two bath developers did not even work with modern films. Thanks for your contributions in this regard.

[sanking]

Thanks for this confirmation Sandy. That would match up exactly with my experience using a diffusion enlarger. I know I have mentioned this before, but before you started working with divided Pyrocat and your article in VC Magazine, people used to tell me I was crazy, and that two bath developers did not even work with modern films. Thanks for your contributions in this regard.

David,

Thanks for the kind words. People knew a lot about two-bath developers "back in the day". Then the Zone system came along and the chemistry and technics appear to have been forgotten, and a lot of myths appeared: two-bath developers don't work with modern films, two bath developers don't work with pre-soak, two-bath developers don't work with constant agitation, etc. I must admit that I even fell for one of the myths also, i.e. that no development takes places in Solution A.

However, many myths have some basis in specific experiences and the formula of Diafine is proprietary, so the formula could have been changed over the years and we would really have no way of knowing. So we get unexpected results that don't necessarily correlate to the experience of others.

For the record, the current packing of Diafine indicates that it contains Sodium Sulfite and Hydroquinone. The current MSDS sheets for Diafine indicate that Solution A contains Hydroquinone and that Solution B contains sodium carbonate. We could guess about other ingredients, but those are the facts that we know.

Sandy

[Ken Lee]

While searching the web for whatever I could find about Diafine, I found several "anecdotal" testimonials and innumerable sample photos: the vast majority poorly exposed, scanned, and described.

Then I ran across Sandy's View Camera article on Diafine, in PDF format (July/August 2008). What a breath of fresh air !!!

Oh yeah. :cool:

[Mark MacKenzie]

Thanks for that. I just downloaded it. It is titled: Two Bath Development for Black and White Film , correct?
at www.viewcamera.com in the subscriber section.

[Ken Lee]

Ken, I hope you can keep posting your experience with Diafine. I am very interested in your approach and testing. Thanks!

Since you asked :) here's another one, with a rather high dynamic range. The end result doesn't look like the range was so high, but it was: from deep indoor shade to a reflection of the light coming through a window. A 45 second exposure, enough under normal conditions to "fry" the high values. Metered with an incident meter in the shadow, with ISO set to double the nominal value.


http://www.kennethleegallery.com/images/forum/PocketBalance.jpg
Salter's Pocket Balance, 2013
Sinar P, 210mm Macro Sironar
4x5 TMY, Diafine

[Mark MacKenzie]

When you say double the ISO, is that the same as double the film box speed?

Had you shot at ISO, do you think the low values would come up in value with highs staying just as they are?

I'm wondering about an into the sun shot with the sun included or at least a full moon...
That's a nice shot there, Ken.

[Ken Lee]

When you say double the ISO, is that the same as double the film box speed?

Had you shot at ISO, do you think the low values would come up in value with highs staying just as they are?


I usually shoot TMY at 200, but with this technique I configured the meter to ISO 400. This is just a quick way of adjusting exposure downward by 1 stop or shutter-speed. If we were to meter the shadows directly with an incident meter - and thus place them on Zone V - they would be overexposed by 1 stop. Phil Davis explains this method in his book Beyond The Zone System, 4th Edition, "Metering for the Incident System" pp 134:

"Notice that these film speeds seem exaggerated; they are, in fact, just double the normal speeds. As explained earlier, this is done deliberately to compensate for the 1-stop overexposure that normally results when the camera settings are based on the low-light incident reading."

Had I shot at box-speed, namely 400, the shadows would be 1 stop darker, as we expect.

With stand development, high values are arrested as the developer gets exhausted, while the shadow values are given much longer time to fill-in. With experience (trial and error) or development by inspection, we can control the process.

With 2-bath development, we simply place the shadows where we want them, and rely on the developer to limit the high values. Because 2-bath development is even simpler and more fool-proof than ordinary development, I have never tried stand development, and may never do so. Because Diafine seems to last "indefinitely", I may never purchase any more, except perhaps to top-off the original batch.

[Mark MacKenzie]

Thanks, Ken. I guess what I am thinking is that we can control the tonal compression by bringing the low tones up or down in value (to a point.) If you had shot at ISO 50, then the shadows alongside the balance would be raised and more infomation. Maybe it would be blander but the control possibilities seem really cool.

Have you also found that the temperature does not have to be consistent? Same development at 66 degrees as at 74? For example?

[Ken Lee]

Thanks, Ken. I guess what I am thinking is that we can control the tonal compression by bringing the low tones up or down in value (to a point.) If you had shot at ISO 50, then the shadows alongside the balance would be raised and more infomation. Maybe it would be blander but the control possibilities seem really cool.

Have you also found that the temperature does not have to be consistent? Same development at 66 degrees as at 74? For example?

Yes to all the above. You might find this recent thread (http://www.largeformatphotography.info/forum/showthread.php?98377-Diafine-Help-please-for-uneven-development) interesting.

Also, have a look at this discussion of Divided Pyrocat (http://www.largeformatphotography.info/forum/showthread.php?52913-Anybody-using-Pyrocat-HD-or-MC-as-a-Compensating-Developer). The principles are very similar.

Sandy King has recommended the combination of divided development (he created Divided Pyrocat) and shadow based incident reading - particularly when shooting roll film - it's very clever :cool:

This approach is not only convenient: it lets us shoot special subjects. I'm beginning to wonder if subjects of high dynamic range have a higher "tonality potential" than other subjects.