Criteria for new developer formulations

[gainer]

Let me get this straight. Am I expected to provide information comparable to the charts and tables Kodak provides for their developers for any formula I suggest in the APUG forums? I would certainly do that if I were expecting to make enough money from sales to cover the cost of such tests. To the best of my knowledge, that is not the purpose of APUG.

If anyone wants to assert that a formula I suggest will not work as I say it did for me, it is usually a simple task to whip up a batch and test the assertion. The promotion of the KISS principle is one of my purposes in life.

 

[Photo Engineer]

When I asked the question about the data that Kodak has provided I was thinking more in terms of visual comparison of grain and sharpness than in characteristic curves and contrast/time charts. The information at Ron's link summarizes what we should expect with different developers, in general, but does not show any specific visual comparisons of grain and sharpness comparing one specific film in different developers. That is the kind of information I would be interested in seeing.

Sandy King

The link Anon provided gives far more information, as does the data sheet for each particular film.

However, the actual picture comparisons were usually presented in the SPSE and ICIS jorunals if they were presented.

PE

 

[Photo Engineer]

Let me get this straight. Am I expected to provide information comparable to the charts and tables Kodak provides for their developers for any formula I suggest in the APUG forums? I would certainly do that if I were expecting to make enough money from sales to cover the cost of such tests. To the best of my knowledge, that is not the purpose of APUG.

If anyone wants to assert that a formula I suggest will not work as I say it did for me, it is usually a simple task to whip up a batch and test the assertion. The promotion of the KISS principle is one of my purposes in life.

Look at my post #64 Patrick.

And consider tihs. Caffeinol is a solution that develops film. D-76 is a film developer. One was designed by tinkerers and the other was designed by professionals. The latter had significant proofs to back it up as a worthy developer for discriminating professionals and it stood the test of time.

Caffeinol has also been around a long time, but I doubt if Ansel Adams would have used it. So, it depends on where you are placed in this continuous scale from tinkerer to professional. See Ray Rogers post above. He said it very well.

PE

 

[Ray Rogers]

Let me get this straight. Am I expected to provide information comparable to the charts and tables Kodak provides for their developers for any formula I suggest in the APUG forums?

I don't think anyone was saying that. Certainly not me!

I would be tickled pink if you were to come up with the ideal developer using your KIS philosophy.

 

[Ian Grant]

When I asked the question about the data that Kodak has provided I was thinking more in terms of visual comparison of grain and sharpness than in characteristic curves and contrast/time charts. The information at Ron's link summarizes what we should expect with different developers, in general, but does not show any specific visual comparisons of grain and sharpness comparing one specific film in different developers. That is the kind of information I would be interested in seeing.

Sandy King

In the past I've seen excellent comparative tests of film & developer combinations but never from any manufacturer. They were quite useful and a bit of an eye opener, but inevitably not every combination could be done.

The major problem is they are time consuming tests and costly and probably no magazines now would pay to have them done again. I don't have the magazines any more, it was possibly Camera, a UK magazine that was around late 70's until the mid 80's. Films have improved since and so the data's no longer valid but it would be great to see something similar again.

I think Ilford published something once in a Guide, or perhaps Jack Coote's B&W Ilford book, but it's odd that Kodak didn't do something.

Ian

 

[Photo Engineer]

Most of the testing was done in magazines like Popular Photography, and the B&W films and developers took back seat to color. Kodak has published data and photos, as I said, but mainly in journals.

PE

 

[gainer]

While we're on the subject, what stroke of true genius discovered that the optimum amounts of Metol, hydroquinone, sodium sulfite and borax were exactly 2.0, 5.0 100.0 and 2.0 grams respectively in water to make 1.o liter? The first mention I see of those proportions was not given a name, but appears ca. 1930 in "The Principles of Optics" by Jenkins and White.

 

[sanking]

The major problem is they are time consuming tests and costly and probably no magazines now would pay to have them done again. I don't have the magazines any more, it was possibly Camera, a UK magazine that was around late 70's until the mid 80's. Films have improved since and so the data's no longer valid but it would be great to see something similar again.

I think Ilford published something once in a Guide, or perhaps Jack Coote's B&W Ilford book, but it's odd that Kodak didn't do something.

Ian

Back in the day the method of testing was fairly simple in that the only possible output was on photographic paper.

Can you imagine how complicated this type of testing would be today when we would have to compare both prints on photographic paper and inkjet prints from scans.?

BTW, I have an old Kodak book on professional black-and-white films that has good illustrations of grain differences among various Kodak films, including Tech Pan, Tmax-100, Plus-X Pan, Tmax-400, Tri-X, and Tmax-3200.

The differences are very clear.

My suspicion is that the reason Kodak never published anything similar to this for film developers, with a specific film, is that the results would have been so close that the difference would not show in reproduction. The plain fact is that with any film/developer combination the film has value of about 90 compared to the developer at 10.

Sandy

 

[Photo Engineer]

Sandy;

I'm not sure that I can agree with your statement that the result across developers would be so close that the difference would not show. We have all seen how different D-76 is compared to XTOL.

PE

 

[Ian Grant]

I think what Sandy means is when you add a reproduction process into the equation.

Back in the 70's/80's it was hard to reproduce the differences between say FP4 in Microphen & HP5 in Perceptol, or Kodak equivalents. Lowe's 1939 book on Developers does include examples abut they shown grain etc but can't show tonality, nor could most magazine or similar tests with normal reproduction techniques.

Ian

 

[Photo Engineer]

Well, again I must say that I have seen the differences even in magazines Ian. And differences could clearly be shown in some of the journal articles I read.

PE

 

[sanking]

Well, again I must say that I have seen the differences even in magazines Ian. And differences could clearly be shown in some of the journal articles I read.

PE

Ron,

And I will say again that I have never seen any comparisons of the effect of different Kodak developers with a specific film in any of the promotional literature published by Kodak. Why not? Kodak has published film comparisons, why not developer comparisons?

Also, IMO the difference in image quality between D76 and Xtol is really quite small. I have tested and made prints using both of these developers and I think one would be very hard pressed to see any difference in overall image quality from either developer in 11X14 and 16X20 prints from MF negatives.


Sandy

 

[Photo Engineer]

Sandy;

Internally, there were many comparisons, but the closest external publication that I find is the comparison of all Kodak films in one developer (I think, as the article is vague) for sharpness and grain at matched contrast and box speed. This was done on p4 of the B&W Darkroom Dataguide. Also, in that same book they show the effects of over and under development and exposure.

We had to have a pretty convincing case to change developers or come out with a new one as this is not an inexpensive proposition. The proponents of this change had to show, internally, their complete case of goals. I havae then seen some of the work published, as I said, in journals but not the trade magazines.

Externally, the comparisons that I saw were left to the magazines. Kodak did not publish anything in them, but did supply the editors and writers with free samples. This continues today.

The only developer comparisons then remain the data in the reference URLs above which are published on the Kodak web site.

PE

 

[sanking]

Ron,

I have a Kodak B&W Darkroom Dataguide, apparently a differnet version from the one you have because in my dataguide the developer information is on p. 6-7.

Back to your original message to start this thread. Many people appear to enjoy mixing new formulas for the fun of it, and most of them are not making any claims to special qualities. That seems perfectly acceptable to me.

I agree that if one introduces a new developer and claims special properties that are different from standard it would be nice to see some proof to back up the claim. However, the criteria you list, which would be ok for a big institution like Kodak, is not at all what I would use. Here would be my criteria.

1. Overall image quality at the largest magnification one would expect to print from a given format, with the print viewed at the optimum viewing distance of 10-12 inches. Grain and sharpness are inherent in this judgment. (70 points)

2. Stability of the stock solution(s). (10 points)

3. Effective film speed, established by sensitometry testing. (10 points)

4. Cost. (5 points)

5. Ease of use. (5 points)

D76 1:1 would be the standard to which I would compare any new formula.

Sandy King

 

[Photo Engineer]

Sandy;

I don't disagree. See my post stating another POV on this a few pages ago. I don't mean that hard data is essential. I can't even get the use of a microdensitometer!

The guideline should have some sort of comparison though to fit your list and D-76 1:1 is fine with me unless you are trying to duplicate HC110 or Rodinal etc... So, I agree with those qualifications ie. Reference prints at the same speed and contrast with the developer of choice that you are trying to "feature" yours as a replacement for.

And, I agree with you. Publishing comparison photos with different developers would be a worth while endeavor for Kodak to undertake. Even though most would probably dismiss it as being non-objective, an argument often seen here. However, in our case, we are often the only ones to do the tests for our own developers.

PE