Designing T-Max Films: TMX speed; In response to David Williams' request

[Augustus Caesar]

What you've found is the reality that a very big percentage of the claims from home darkroom users about acutance often boil down to people failing to identify intermittent vibration or alignment problems in enlargers, or using consumer grade scanners that are fundamentally unsharp.



I'd agree that XP2 Super (having printed and scanned a lot of images from it in adequately tightly controlled conditions, and in comparison to many conventional BW films and developers) is very sharp and fine grained in the highlights (just with more apparent granularity in the shadows as usual for chromogenics) - I think the main reason people don't like it is that it very firmly demonstrates the abilities of real photographic engineering to deliver an actual compensated highlight curve without mucking up the toe or midrange (assuming the end user has the baseline ability to expose it sensibly enough to get a print with decent highlights on less than G5) and they deliver their most optimal results in utterly normal C-41, not something cooked up in a garden shed by people in active denial of post-1945 photographic science. What's more amusing still is that there's an article to be found in the depths of some US photo magazine or other from the early 1980s where one of the creators of cookbook-repeated POTA derivatives for Tech Pan states that he's given up on technical films and specialist developers in favour of XP1...



The big discovery seems to have been that specific PQ ratios could do what very dilute (0.5g/l) metol only developers could do, but with the ability to be used across a much wider array of circumstances (and especially in replenished systems), with an easier choice of pH optimisations for fine grain or sharpness. And emulsions changed to maximise developer interactions for beneficial inhibition effects in the manner of the DIR couplers in chromogenic/C-41.



Not really, at least not those made with reasonably modern technology. They do tend to develop faster (and may go to higher max densities), so it's more accurate to describe some as being rather less resistant to gross user error (and some have engineered-in components to regulate the development time for this reason).

Yes, really. No matter how you develop them, very slow films have less latitude. The reason is that the range of grain sizes is small, unlike faster films, which have a wider range of grain sizes.

 

[Milpool]

Yes, really. No matter how you develop them, very slow films have less latitude. The reason is that the range of grain sizes is small, unlike faster films, which have a wider range of grain sizes.

I don’t think it’s a hard and fast rule. Panatomic X was quite slow but had a fairly long scale with a relatively gradual shoulder, not all that different a characteristic curve than TMX and Delta 100.

Granted Panatomic X is somewhat of an outlier but it suggests slow, very fine grain negative emulsions can be made to have similar sensitometry to medium speed films.

 

[pentaxuser]

Basically yes, although D-23 would likely be slightly coarser grained than Perceptol and perhaps give very slightly higher emulsion speed.

Why - the coarser grain of D23 being the result of sodium chloride but that brings us back whether sodium chloride does reduce the size of grain salt to which the answer was No hence my original question?

If the inclusion of sodium chloride is not responsible then what else causes D23 to have coarser grain than Perceptol?

Thanks

pentaxuser

 

[pentaxuser]

Perceptol without salt isn't Perceptol - it's integral to the formula itself. And dilute D-23 doesn't give the same effect as dilute Perceptol, so there's that. Some of the comments on this thread seem like armchair quarterbacking - opinions without the experience to back it up (and I don't mean smudgy web scans as alleged "evidence" for this or that).

So that's an answer of sorts to my original question but it begs the further question of how does the difference or how do the differences(plural) reveal themselves such that I would immediately see what they were if I were to be presented with a set of prints

Thanks

pentaxuser

 

[ags2mikon]

Could it be the higher amount of Elon in the formula? IDK.

 

[Paul Verizzo]

It wouldn't be the worst option in the world to use TMY for everything either.

Yup. If I had to shoot only one B&W film, TMY-2 would be it. Now, if I could only afford a new bulk roll....

 

[Paul Verizzo]

I thought chromogenic XP2 was the least versatile, most characterless film I ever encountered. Soft-edged is an understatement in its case. I also wonder how long those dyes will hold up. But to each his own. I at least tried it ... kinda like the brief Tech Pan rage in pictorial photography - another mismatch - but in the opposite direction, contrast-wise.

Indeed. With a hybrid "darkroom," just shoot color and convert to B&W. Outstanding. FWIW, the best color negative film Kodak ever made was a consumer product, HD400 in 24 exposure rolls. Very sharp, hence the HD.

I still have quite a few rolls frozen, although I've not shot any in a long time.

 

[Paul Verizzo]

I just tried to google the date of transition from old tmax to TMY-II and I do not trust the results I am seeing. I have a chance to get some 2008 confirmed frozen Tmax 400 in 4x5 for a really attractive price compared to current retail.

According to Microsoft Copilot, TMY-2 came out in 2007, more available in 2008. This confirms my own recollection. In 35mm. the edge marking will say so.

 

[DREW WILEY]

There was also a renaming tweak on the boxes, from TMax 100 to 100 TMax; TMax 400 to 400 TMax.

 

[Prest_400]

Indeed. With a hybrid "darkroom," just shoot color and convert to B&W. Outstanding. FWIW, the best color negative film Kodak ever made was a consumer product, HD400 in 24 exposure rolls. Very sharp, hence the HD.

I still have quite a few rolls frozen, although I've not shot any in a long time.

Despite my age (30) I unironically forget about the digital editing side; but shooting B&W for the sake of darkroom printing down the line.
Some acquaintances have printed B&W off color negs with variably ok results (weird tonality) and I did think of Lithing from a B&W.

In contemporary forums such as photo.net there were quite some good words about Kodak HD films. I'd guess some of the tech should have been incorporated to the CN line that survives now.

Anyways about the T-Maxes, not so much more remarks.

Ah, its base! Kodak has migrated the color still films to ESTAR. IIRC the message was that B&W will be continued to be on Acetate due to antistatic properties, perhaps more a 35mm thing. But I'd guess it's the engineering required as well as production volumes not facilitating it?

As a 120 user, I really buy into PET base given the dimensional and archival properties.

 

[DREW WILEY]

Current Kodak color neg films are way better than they were in the past, the result of incremental evolution, and still represent an ample selection. No point in going backwards unless one is just seeking some vintage look.

 

[Milpool]

The basic principle on which Perceptol and earlier Microdol are based is the addition of sodium chloride to a metol-sulfite (D-23 type) developer to produce finer grain at the slight expense of emulsion speed and traditionally acutance.

I think we’re all in agreement Perceptol is intended to produce finer grain, and that this effect will be lessened as the developer is diluted from stock strength, as it would for any solvent developer.

At issue seems to be whether or not the dilution of Perceptol enhances/produces edge effects with TMX, and if it does, why this would be unique to Perceptol. Aside from metol, sulfite and NaCl Perceptol doesn’t appear to contain additional photographically active ingredients, which would mean if it is behaving differently than say D-23 to any significant degree it would have to be the NaCl doing something special. I think Drew said he mixes his own, which is further support for the only potentially magic ingredient being NaCl.

NaCl is a relatively mild silver halide solvent and also a weak restrainer. Based on the research I’ve seen I have my doubts it can produce more meaningful TMX edge effects at 1+3 than similarly dilute D-23 etc. and I haven’t observed anything remarkable myself but anything is possible, I suppose, and there’s no point arguing about it. You also have to buy into the notion TMX isn’t a sharp film to begin with. That is perhaps worth more of an argument since it just isn’t the case.

Why - the coarser grain of D23 being the result of sodium chloride but that brings us back whether sodium chloride does reduce the size of grain salt to which the answer was No hence my original question?

If the inclusion of sodium chloride is not responsible then what else causes D23 to have coarser grain than Perceptol?

Thanks

pentaxuser

 

[pentaxuser]

The basic principle on which Perceptol and earlier Microdol are based is the addition of sodium chloride to a metol-sulfite (D-23 type) developer to produce finer grain at the slight expense of emulsion speed and traditionally acutance.

I think we’re all in agreement Perceptol is intended to produce finer grain, and that this effect will be lessened as the developer is diluted from stock strength, as it would for any solvent developer.

At issue seems to be whether or not the dilution of Perceptol enhances/produces edge effects with TMX, and if it does, why this would be unique to Perceptol. Aside from metol, sulfite and NaCl Perceptol doesn’t appear to contain additional photographically active ingredients, which would mean if it is behaving differently than say D-23 to any significant degree it would have to be the NaCl doing something special. I think Drew said he mixes his own, which is further support for the only potentially magic ingredient being NaCl.

NaCl is a relatively mild silver halide solvent and also a weak restrainer. Based on the research I’ve seen I have my doubts it can produce more meaningful TMX edge effects at 1+3 than similarly dilute D-23 etc. and I haven’t observed anything remarkable myself but anything is possible, I suppose, and there’s no point arguing about it. You also have to buy into the notion TMX isn’t a sharp film to begin with. That is perhaps worth more of an argument since it just isn’t the case.

Thanks for this So from what you say Sodium Chloride( let's call it salt for simplicity) has to be responsible for Perceptol's alleged finer grain compared to D23 but why is that?

Others seem to say that salt does not have this effect Has anyone tried to make darkroom prints of the same size of identical negatives processed in Perceptol and D23 and from this, can state that the salt makes a difference?

Patrick Gainer's test was admittedly with D23 but if this is Perceptol minus the salt and we conclude that salt is the only difference between the 2 it seems a fair assumption that the test with D23 plus salt was a test with Perceptol

I had a look at his article and was hard pressed, as seemingly he wa,s to see the difference between D23 with no salt and D23 plus salt. His examples were the equivalent of two 28x42 inch prints from a 35mm film

It doesn't look from Gainer's tests that there is much of a case for salt reducing grain in Perceptol compared to D23

However if anyone can show evidence that there is a case then can they help me by showing it ?

Thanks


pentaxuser

 

[John Wiegerink]

Thanks for this So from what you say Sodium Chloride( let's call it salt for simplicity) has to be responsible for Perceptol's alleged finer grain compared to D23 but why is that?

Others seem to say that salt does not have this effect Has anyone tried to make darkroom prints of the same size of identical negatives processed in Perceptol and D23 and from this, can state that the salt makes a difference?

Patrick Gainer's test was admittedly with D23 but if this is Perceptol minus the salt and we conclude that salt is the only difference between the 2 it seems a fair assumption that the test with D23 plus salt was a test with Perceptol

I had a look at his article and was hard pressed, as seemingly he wa,s to see the difference between D23 with no salt and D23 plus salt. His examples were the equivalent of two 28x42 inch prints from a 35mm film

It doesn't look from Gainer's tests that there is much of a case for salt reducing grain in Perceptol compared to D23

However if anyone can show evidence that there is a case then can they help me by showing it ?

Thanks


pentaxuser

pentaxuser,
You just challenged all the "Mad Scientist" here! I'm sure they are tying the stings to their lab aprons as I type this. As for me, I'm just going to keep using my homemade Percptol 1+3 and maybe even try it at 1+4. Life is just too damn short!

 

[Lachlan Young]

At issue seems to be whether or not the dilution of Perceptol enhances/produces edge effects with TMX, and if it does, why this would be unique to Perceptol. Aside from metol, sulfite and NaCl Perceptol doesn’t appear to contain additional photographically active ingredients, which would mean if it is behaving differently than say D-23 to any significant degree it would have to be the NaCl doing something special. I think Drew said he mixes his own, which is further support for the only potentially magic ingredient being NaCl.

NaCl is a relatively mild silver halide solvent and also a weak restrainer. Based on the research I’ve seen I have my doubts it can produce more meaningful TMX edge effects at 1+3 than similarly dilute D-23 etc. and I haven’t observed anything remarkable myself but anything is possible, I suppose, and there’s no point arguing about it. You also have to buy into the notion TMX isn’t a sharp film to begin with. That is perhaps worth more of an argument since it just isn’t the case.

On the other hand, and perhaps a little counter-intuitively, if the person making the claim about dilute Perceptol/ Microdol-X has very limited experience of the edge effect enhancement/ development inhibition characteristics of more solvent developers on modern emulsions, and the level of NaCl in diluted Microdol-equivalent is just enough for a 1+3 dilution to retain even a slight level of solvency, it could make things seem a bit sharper than they might think (relative to their use of utterly non-solvent staining developers) - and consequently misattribute.

 

[Milpool]

An issue with Gainer’s experiments is that there never seems to be any sensitometry to confirm things were developed to the same gradient etc. Maybe the results are illustrative, maybe not. It also might depend on the film involved.

With respect to the addition of sodium chloride to solvent developers to increase solvent effects, this is all old, well documented stuff in the literature.

As is usually the case it is basically up to the individual to try things and decide if it works or doesn’t work. Nobody has contemporary objective/definitive information to show. At one time I thought it might be interesting to experiment with - I went as far as acquiring the magic Microdol-X ingredient - but didn’t get around to doing the work.

None of this is to say Perceptol wouldn’t be a good developer to use with TMX. I’m sure it would do perfectly well. Ilford certainly doesn’t shy away from recommending it for use with modern films like Delta for extra fine grain, if that’s any indication.

Also, as Lachlan points out, as emulsion technology progressed the old rules about what kinds of developers would do what became somewhat less definite.

Thanks for this So from what you say Sodium Chloride( let's call it salt for simplicity) has to be responsible for Perceptol's alleged finer grain compared to D23 but why is that?

Others seem to say that salt does not have this effect Has anyone tried to make darkroom prints of the same size of identical negatives processed in Perceptol and D23 and from this, can state that the salt makes a difference?

Patrick Gainer's test was admittedly with D23 but if this is Perceptol minus the salt and we conclude that salt is the only difference between the 2 it seems a fair assumption that the test with D23 plus salt was a test with Perceptol

I had a look at his article and was hard pressed, as seemingly he wa,s to see the difference between D23 with no salt and D23 plus salt. His examples were the equivalent of two 28x42 inch prints from a 35mm film

It doesn't look from Gainer's tests that there is much of a case for salt reducing grain in Perceptol compared to D23

However if anyone can show evidence that there is a case then can they help me by showing it ?

Thanks


pentaxuser