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View Full Version : XTOL Replenished for TMAX 400, JOBO Rotary anybody?



Thomas Greutmann
7-Nov-2010, 07:24
Hello,
I shoot mostly TMAX 400 and do my development in XTOL, using Jobo 2500 tubes with Rotary Processing. I have seen quite a few posts in this and other forums saying that XTOL will work even better when replenished and I would like to give it a try.

However Kodak does not publish any development times for this particular combination (table entries are blank), and I have seen a post saying that replenishing and Jobo rotary processing does not work together, no reason given.

Does anybody have experience with this particular combination and would be willing to share their experience? Any hint on development times or replenishment quantities?

Thanks in advance

jeroldharter
7-Nov-2010, 08:02
That is a problem with replenishment systems: how do you test for development times? I don't see the point with a Jobo. If I were using tanks with large volumes then I might use replenishment for economical and practical reasons, but one shot developers are the way to go with a Jobo.l

Peter De Smidt
7-Nov-2010, 08:55
You'd have to get the system stabilized by running a fair number of films before running tests. This would be a great use of really expired film.

My guess is that replenishment will cause bromide (a restrainer) to increase over what's in fresh developer. This should require slightly lengthened development times. Perhaps 10%?

Jay DeFehr
7-Nov-2010, 09:16
Jerold,

I don't understand your question, "how do you test for development times?". How would replenishment change the way one tests for development? One shot developers certainly simplify things, but that doesn't necessarily mean they produce better results or economy. If one's process is in control, replenished systems can be very consistent and very economical. Once your system is started and in control, the replenishment rate (70ml/liter) is all one uses for each roll/sheet of film developed.

Thomas,

Kodak mentions in Tech Pub J109, "Some rotary processors allow the use of replenished developer, see Replenishment." I think the times given for sheet film in a replenished system provide a starting point for personal testing. For TMY-2.

The challenge of a replenished system is in monitoring and maintenance.

http://www.kodak.com/global/plugins/acrobat/en/service/Zmanuals/z-133.pdf

The above provides a good overview of the principles and practice of process control and monitoring.

tgtaylor
7-Nov-2010, 09:29
However Kodak does not publish any development times for this particular combination (table entries are blank), and I have seen a post saying that replenishing and Jobo rotary processing does not work together, no reason given.

Thanks in advance

The most logical reason would seem to be the amount of oxygen that rotary processing introduces into the developer. After several minutes of rotary processing the developer (and fix) is pretty well 'aired-out' and I imagine that all the molecules have an oxygen attached to its receptor.

That said, I have no experience using Xtol replenished. I use Xtol 1:1, 1:2, and 1:3 one-shot in a Jobo and to "capacity" in dip n dunk tanks.

BTW, I wouldn't recommend a water soak prior to processing unless you compensate for it by reducing the development time.

Thomas

jeroldharter
7-Nov-2010, 10:29
Jerold,

I don't understand your question, "how do you test for development times?". How would replenishment change the way one tests for development? One shot developers certainly simplify things, but that doesn't necessarily mean they produce better results or economy. If one's process is in control, replenished systems can be very consistent and very economical. Once your system is started and in control, the replenishment rate (70ml/liter) is all one uses for each roll/sheet of film developed.
...

I understand what you mean. I am sure it is possible to calibrate a replenished system. If I ran a lab and processed a lot of film daily, it might have appeal. However, testing is tedious and time consuming. Processing 5 runs of film through a Jobo for BTZS testing, then running them through a densitometer, etc. is not Herculean but it easily eats up half a day. (One instance in which BTZS tubes are faster than Jobo drums is testing.) So the only way you can confirm that development is consistent in a replenished system it to run tests at various degrees of replenishment. So you would have to run many sheets of film through in between tests, then repeat the tests at points x/y/z and then compare the test results. What if the testing shows some inconsistency? Is it the testing itself? Is it the replenishment rate? Is it temperature variation between runs? Is it...? It just seems needlessly complicated and time consuming.

Jay DeFehr
7-Nov-2010, 11:39
Jerold,

Check out the link I posted for the Kodak process control system. Testing the system is done with process control strips. Film testing is done separately. One doesn't use BTZS testing to test one's process. I agree that maintaining a replenished process is more time consuming than using a one-shot developer, but nothing like as complicated as you describe above. In the end, it comes down to results. If one prefers the results obtainable by the use of a replenished system, I think the effort to maintain one is justified, and not too much of a burden. It's certainly more practical for those who process regularly than for those who process only occasionally, with long gaps in between. Because of my work schedule, my processing is regular, with a fairly high volume for 3 weeks, and then very minimal for the next three, on a rotating basis. Lately I've been using a superfine grain developer of my own formulation, in a replenished system. When I begin my 3 weeks of processing, I test to see where the process is in regard to aim values, and adjust as needed. Since I'm using a relatively low volume of working developer, adjustments take effect almost instantly, and I can get on with processing. Over the three weeks that follow, I test my system after every 5 rolls of film are processed, which would be overkill for an established developer, like Xtol, but useful for evaluating my own developer formula.

Maintaining a replenished system involves a learning curve, but once one gets comfortable with the process, it provides much peace of mind, knowing one's process is in control, and one's results consistent and predictable.

Using a developer like Xtol, D-76, etc., one shot is not as dead consistent as many like to imagine. Every time one mixes up a working solution, several opportunities for error arise. As the stock solution is used, the ratio of remaining developer volume to exposure to air increases, along with the duration of the exposure, making the last working solution potentially much different than the first mixed from a given stock solution. Then there's the potential for contamination, or water quality differences, or measurement errors, or some combination of the above. Certainly, a more stable and concentrated stock solution minimizes these problems, but it won't eliminate them completely. I guess my point is that there's no free lunch, and consistency requires diligence, whatever system one employs.

Mark Barendt
7-Nov-2010, 12:54
You will probably add about 10% to your normal full strength time once you are fully seasoned.

Seasoning depends on how big your working solution bottle is. My bottle is 1.75 liters and it took about 12 rolls to get fully seasoned and stable, 1-liter probably 8 rolls.

It has been absolutely stable and reliable ever since I finished seasoning.

During the seasoning process, the time stretches out gently, probably about 1% extra time for each roll completed.

During the seasoning just top up the working bottle to keep it completely full, might take 10ml or so per roll.

Once you have run your 8-12 rolls start the "bleed". Pour a full 70 ml of fresh Xtol into the working solution bottle for each roll you process then pour the "used" Xtol in until the bottle overflows, discard the rest.

Sirius Glass
7-Nov-2010, 18:23
That is a problem with replenishment systems: how do you test for development times? I don't see the point with a Jobo. If I were using tanks with large volumes then I might use replenishment for economical and practical reasons, but one shot developers are the way to go with a Jobo.l

This does not make sense. There is no need to test replenished XTOL.

Steve

jeroldharter
7-Nov-2010, 18:27
Apparently I don't know what I am talking about. I'll yield to those who do. Nevertheless, despite difficult to control variables in any method, I think 1-shot would be more consistent for the typical darkroom.

Sirius Glass
7-Nov-2010, 18:31
I used replenished XTOL with 4"x5" Ilford HP5+. I used the time recommended by Ilford which was 9 minutes (8 minutes plus 1 minute for the replenishing) at 68F and reduced that time by 15%, as recommended by Ilford, because I am using the Jobo. The negatives were thin. I asked on APUG and Penn Camera, and the overwhelming response was to not reduce by 15%, use the full time. So I used 100% of the time [9 minutes] the results were great.

Steve

Sirius Glass
7-Nov-2010, 18:37
Replenished XTOL gives much more consistent results with better tonal quality than one shot. That is why replenished XTOL is used. Unlike some other developers, XTOL is replenished with stock XTOL rather than another chemical. There are many threads on APUG talking about the advantages of replenished XTOL over non-replenished XTOL or one shot XTOL.

Steve

jeroldharter
7-Nov-2010, 18:40
Live and learn... Thanks.

Sirius Glass
7-Nov-2010, 18:46
Live and learn... Thanks.

I was skeptical until I tried it.

Steve

Peter De Smidt
7-Nov-2010, 21:35
Replenished XTOL gives much more consistent results with better tonal quality than one shot. That is why replenished XTOL is used. Unlike some other developers, XTOL is replenished with stock XTOL rather than another chemical. There are many threads on APUG talking about the advantages of replenished XTOL over non-replenished XTOL or one shot XTOL.

Steve

Steve, I'm not sure what you mean by more consistent results, or better tonality. I used Xtol for years one shot. It was as consistent as any developer I've used, and my densitometer agrees. How is the replenished version more consistent? Regarding tonality, it gave a pretty straight line response with the films I used, mainly TMX and TMY. Does the replenished version give a different curve shape?

Mark Barendt
8-Nov-2010, 05:42
Steve, I'm not sure what you mean by more consistent results, or better tonality. I used Xtol for years one shot. It was as consistent as any developer I've used, and my densitometer agrees. How is the replenished version more consistent? Regarding tonality, it gave a pretty straight line response with the films I used, mainly TMX and TMY. Does the replenished version give a different curve shape?

Replenished Xtol has the same advantages as dilution.

IanG
8-Nov-2010, 06:05
Replenished Xtol has the same advantages as dilution.

It has some additional advantages as well, usually any developer ID-II/D76, Xtol etc used dilute gives an increase in grain size due to there being less sulphite present, additionally there tends to be slight compensation because the developer exhausts particularly at 1+3.

Overall the replenished developer has the advantages of better sharpness and excellent tonality with the finest grain achievable with the particular developer used.

One big disadvantage of using Xtol dilute in a Jobo is you will get close to the exhaustion point with the smaller volumes of chemistry used.

I've been using Replenished developers for over 40 years and it's a simple and reliable method of working.

Ian

jeroldharter
8-Nov-2010, 06:57
...

I've been using Replenished developers for over 40 years and it's a simple and reliable method of working.

Ian

How long do you keep the developer solution before tossing it and starting out fresh?

IanG
8-Nov-2010, 07:16
How long do you keep the developer solution before tossing it and starting out fresh?

Really depends on the throughput and the period of time, up to a year, sometimes a bit longer, but with heavy through put then more like 6 months.

In the past I shared a deep tank line with 2 other photographers, that was heavy usage, quite a few films & sheets of 5x4 per day. :D

Up until last year I used a 5 litre pack of Xtol split into 2.5 litres of working solution the rest as the replenisher, but with traveling between two locations a few thousand miles apart it became impractical.

One major advantage for me was the developer, stop & fixer were almost at the right temperature, I'd adjust quickly by placing the bottles in a bowl of water while loading the films, and with no need to measure volumes, just fill the tank(s), it allowed very quick process cycles with minimal preparation times.

I'd replenish every 10 films

Ian

Jay DeFehr
8-Nov-2010, 08:25
Overall the replenished developer has the advantages of better sharpness and excellent tonality with the finest grain achievable with the particular developer used.

Ian

Ian,

How does a replenished solution deliver BOTH better sharpness and finer grain?

According to Kodak, diluting Xtol gives better sharpness and speed at the expense of coarser grain, relative to Xtol stock. A replenished Xtol should produce even finer grain and less speed than undiluted Xtol used one shot, since the developing products that accumulate in the replenished solution have a restraining effect on the developer. If, as you say, dilute Xtol used in rotary processing approaches exhaustion, it could explain improved tonality with replenished developer. One shot developers, dilute developers, and replenished developers each have their advantages and disadvantages, and there are always trade offs between them, in my experience.

IanG
8-Nov-2010, 09:35
The increased sharpness comes from the way the seasoned developer builds up an equilibrium of Bromide & Iodide, and this in turn with the high Sulphite level also helps with the finer grain. The restraining effect is more about development time rather than film speed.

In a dilute scenario of say 1+3 the bromide & iodide released during process are more significant and act in the same way as in a replenished developer.

Remember that developers like D76 (& Xtol) were designed to be replenished from the outset, Kodak originally suggested a different Fine Grain developer for small scale use back in 1927. (Haist's H76 is close to this)

So while there may be advantages in using one shot & dilute developers there's greater advantages in using replenishment if your shooting enough film each month. This is more about the economics of the no of films processed over the developers life.

I don't use Rotary processors, rather Jobo & Paterson inversion tanks, and so the economics are easy a 5 litre pack of Xtol used one shot at 1+2 processes 90 sheets of 5x4 film, whereas replenished that rises to 158 sheets. More when you replenish further with a fresh pack of Xtol, more like 285 sheets per 5 litres.

In practice Kodak's replenishment factor of 70ml per 80 sq inches (4 5x4's) or 120/35mm film is rather more than is needed and as it's a bleed system you are removing some developer to add the fresh.

Once your used to using replenished developers you find it's easy to keep the stock well balanced.

Ian

Jay DeFehr
8-Nov-2010, 11:15
Ian,

I am pretty familiar with replenished systems, having run a color lab. I disagree with your assertion that developer products are more significant with dilute developers. You say the increased sharpness produced by replenished developers results from the build up of developer products, but I think the increased sharpness produced by dilute developers is a consequence of the lower sulfite concentration, since dilute developers also produce higher film speeds, which would not be the case if the development products were responsible. A decrease in film speed is an indicator of under replenishment in a replenished system, because of the accumulation of developer products.

I agree that replenishment is more economical than one-shot use, but not by much, and only after a significant volume of film is developed. The minimum volume of stock required per roll of film developed is 100ml, and the replenishment rate is 70ml per roll. So, 1 liter of Xtol stock will develop 10 rolls of film, one shot, whatever the dilution. That same liter of stock, divided into 500ml of working developer and 500ml of replenisher will develop 7 rolls of film. Add another liter of replenisher, and it will develop another 14 rolls of film, for a total of 21 rolls with 2 liters of stock. That same 2 liters of stock will develop 20 rolls, one shot.

It might well be true that less than 70ml/roll is required to keep one's system in control, or it might take more than 70ml, and it doesn't matter that it's a bleed system; the replenishment rate is the rate of consumption.

Keeping a replenished system in control requires diligence. If one does not have process control strips, a calibrated densitometer, and a good program, one is just winging it, and might be better off using the developer one shot.

Sirius Glass
8-Nov-2010, 17:27
It has some additional advantages as well, usually any developer ID-II/D76, Xtol etc used dilute gives an increase in grain size due to there being less sulphite present, additionally there tends to be slight compensation because the developer exhausts particularly at 1+3.

Overall the replenished developer has the advantages of better sharpness and excellent tonality with the finest grain achievable with the particular developer used.

One big disadvantage of using Xtol dilute in a Jobo is you will get close to the exhaustion point with the smaller volumes of chemistry used.

I've been using Replenished developers for over 40 years and it's a simple and reliable method of working.

Ian

A little logic here. If there were no advantages to replenishing XTOL, Edwal 7, D76, ... et al the manufacturing companies would not put forth replenishing as an option. Why don't you try it for 10 or 20 rolls of film and see the difference for yourself? I saw it in only a few rolls.

If you never tasted or smelled chocolate, how could you say that you do not like chocolate?

This is not a case of "If your friends jumped off the roof ...".

Steve

Jay DeFehr
8-Nov-2010, 17:35
Steve,

I think Ian agrees there are advantages to using replenished developers, and uses one himself. Did you not read his post? Or, perhaps your remarks are not intended for Ian? I'm confused.

Sirius Glass
8-Nov-2010, 17:58
Steve,

I think Ian agrees there are advantages to using replenished developers, and uses one himself. Did you not read his post? Or, perhaps your remarks are not intended for Ian? I'm confused.

I was expanding on what Ian said. Ian and I are in violent agreement on this one. :)

Steve

Jay DeFehr
8-Nov-2010, 19:30
Hahahhaha. I see! Well, if your remarks were directed at me, you're preaching to the choir again. Lately I've been using my own superfine grain developer, replenished. I never suggested there weren't advantages to a replenished developer; I simply disagreed with Ian about what some of them are, why they are, and to the extent of the advantages. I'm perfectly willing to sacrifice some sharpness in favor of finer grain, and I'll even live with a slight loss of film speed, but I don't delude myself into believing I get sharper images with finer grain, and better economy by using a replenished developer, and I certainly don't want to try to convince others of this. Replenished developers can be fantastic, but they are not superior to one shot developers in all ways, for all users. I don't concur with the claim that one shot developers are necessarily and always more consistent than replenished ones, or visa versa. I do believe that any given developer will produce finer grain replenished than it will used one shot, and I also believe it will be less sharp, and produce less film speed. How much less will vary with developer, and much of the time the differences we discuss are very small indeed. Yes, I'll agree that a dilute developer of the D-76 type will produce sharper negatives when diluted than when used stock, or replenished. I'll also agree that negatives developed with intermittent agitation will be sharper than those developed with continuous agitation, all other things being equal. Given the very small differences we're discussing; would a negative developed in a replenished developer with intermittent agitation be as sharp, or sharper than one developed in a dilute, one shot developer with continuous agitation? Who knows? I think we're splitting hairs. The best developer, and the best way to use it have a lot more to do with the user than we seem to be willing to admit or recognize.

IanG
9-Nov-2010, 03:35
Ian,

I am pretty familiar with replenished systems, having run a color lab. I disagree with your assertion that developer products are more significant with dilute developers. You say the increased sharpness produced by replenished developers results from the build up of developer products, but I think the increased sharpness produced by dilute developers is a consequence of the lower sulfite concentration, since dilute developers also produce higher film speeds, which would not be the case if the development products were responsible. A decrease in film speed is an indicator of under replenishment in a replenished system, because of the accumulation of developer products.
.

The Iodide and Bromide from the film becomes more significant with the highest dilutions 1+3 of Xtol, ID-11/D76 simply because the level of developing agents is far lower and in this respect because of the low sulphite as well, the overall effect is more a kin to the European acutance developers of the 1950's & 60's.

When the developer is used full strength with or without replenishment there is always excess developing agents, but at 1+3 particularly in a rotary Jobo the developer ends up close to exhaustion so the by products have far greater importance.

As to the best sharpness the replenished developer will give the best all round combination because it's sharp with finer grain and so gives better definition and smother tones.

Sharpness is relative, the high acutance developers like Kodak HDD, Ilford Hyfin and Paterson Acutol-S gave razor like sharpness but at the expense of increased grain and stark tonality.

There's actually a balance point when using Xtol, Perceprol, ID-11/D76 etc dilute which is close to a 1+2 dilution which is surprisingly never suggested by manufacturers.

Ian

Jay DeFehr
9-Nov-2010, 13:00
The Iodide and Bromide from the film becomes more significant with the highest dilutions 1+3 of Xtol, ID-11/D76 simply because the level of developing agents is far lower and in this respect because of the low sulphite as well, the overall effect is more a kin to the European acutance developers of the 1950's & 60's.

When the developer is used full strength with or without replenishment there is always excess developing agents, but at 1+3 particularly in a rotary Jobo the developer ends up close to exhaustion so the by products have far greater importance.

As to the best sharpness the replenished developer will give the best all round combination because it's sharp with finer grain and so gives better definition and smother tones.

Sharpness is relative, the high acutance developers like Kodak HDD, Ilford Hyfin and Paterson Acutol-S gave razor like sharpness but at the expense of increased grain and stark tonality.

There's actually a balance point when using Xtol, Perceprol, ID-11/D76 etc dilute which is close to a 1+2 dilution which is surprisingly never suggested by manufacturers.

Ian

Ian,

I still disagree that the developer products in a dilute developer are more significant than in a replenished one. I understand your theory, but it isn't borne out in practice. Dilute developers produce higher film speeds, which contradicts the notion that the developing agents are being overwhelmed by restraining development products.

When you write "best sharpness" as opposed to "sharper" or "More sharp", and "all around combination" I think we come closer to agreement. As I wrote in an earlier post, the combined characteristics of grain, sharpness, film speed and gradation make up an Image Quality package, and I agree that the packages produced by some replenished developers suit me better than the packages produced by some one shot developers. Maximum sharpness is not essential for me, so I'm happy to compromise in favor of fine grain, but I don't want to give up much film speed in the bargain, and fine gradation is essential, above all. Others might prioritize these characteristics differently, and for some, a replenished developer might represent an unacceptable compromise.

Still, I understand your use of more absolute terms. For me, my SFG developer in combination with TMY-2 represents the best overall IQ package I've ever seen- much better than Xtol replenished- but I understand others might not agree with my assessment, and that wouldn't make them wrong.

Peter De Smidt
9-Nov-2010, 14:44
A little logic here. If there were no advantages to replenishing XTOL, Edwal 7, D76, ... et al the manufacturing companies would not put forth replenishing as an option.

Steve

Well, cost is certainly an advantage in some situations. I"m still not sure what you meant by "better tonality," though. How does replenished xtol change the characteristic curve of, say, TMY, as compared to the developing the film in one shot Xtol?

Jay DeFehr
9-Nov-2010, 15:37
Peter,

I can't speak for Steve, there's more to gradation (tonality) than the shape of a characteristic curve. Imagine a characteristic curve, of any shape you like, made of stair steps instead of a smooth, continuous line. The larger and fewer those steps are, the coarser the gradation, even though the general shape of the curve isn't changed. Gradation is the product of many interrelated characteristics, but most directly, the combined effects of local, regional and global contrast that are difficult, or impossible to quantify, but create a subliminal impression in the viewer. In a finely graded image, areas that appear to be of a single tone are made up of multiple tones, very close in value, and therefore, the transitions between tones are more seamless. In a coarsely graded image the tones appear blocky, and the transitions between them abrupt, even though the fine and coarse images might share identical curve shapes and contrast indices.

I hope I don't seem to be lecturing, but I often see those who refer to tonality or gradation criticized, as if they're referring to an imagined phenomenon. While gradation might be difficult to quantify, it is, for me, the single most important characteristic of a negative and the prints made from it.

Sirius Glass
9-Nov-2010, 16:23
Well, cost is certainly an advantage in some situations. I"m still not sure what you meant by "better tonality," though. How does replenished xtol change the characteristic curve of, say, TMY, as compared to the developing the film in one shot Xtol?

Jay and Ian have hit all the high lights [pun very much intended] that I am thinking of so I will not use more bandwidth.

Steve

Peter De Smidt
9-Nov-2010, 17:12
Peter,

I can't speak for Steve, there's more to gradation (tonality) than the shape of a characteristic curve. Imagine a characteristic curve, of any shape you like, made of stair steps instead of a smooth, continuous line. The larger and fewer those steps are, the coarser the gradation, even though the general shape of the curve isn't changed.

I don't disagree that a film and developr combo that gives a stair stepped curve would look different than one that gives a smoother curve. But in that case, they aren't the same curve.

Sure, some developer/film/method combos give different tonality than others, but is that the case here, as Steve has claimed, but neither explained nor given evidence for? It's so easy to slip from the claim that something has worked really well for a particular person to the claim that something is better full-stop.

If someone makes a claim but can't even explain what the claim is, then there's very little reason to take the claim seriously.

Sirius Glass
9-Nov-2010, 18:05
It's so easy to slip from the claim that something has worked really well for a particular person to the claim that something is better full-stop.

I never said a word about "full-stop".


If someone makes a claim but can't even explain what the claim is, then there's very little reason to take the claim seriously.

This subject has been thoroughly discussed on APUG and several other sites by people have expound on their test and testing methods. As far as making claims, you have implied that I stated claims about the effect of developers on film speed. Since that is patently false, I can never take anything you say seriously. I will now view all you posts as comic relief.

Steve

Jay DeFehr
9-Nov-2010, 19:43
Peter,

I understand what you're saying, and I agree, in principle. Perhaps my example of a stair stepped curve was not a good one, but I meant it as an abstract example, not that the curve would literally be stair stepped. There's no way to quantify, or graphically represent gradation beyond the visual appearances of images of differing gradations, so abstract examples are a way of visualizing the concept itself. Perhaps a more comprehensible example would be a characteristic curve plotted from one million points vs one plotted from ten points; while the shapes and gradients might be identical, the one plotted from a greater number of points would be much smoother than the the one plotted from just a few points. Again, this is an abstraction because characteristic curves are only abstractly related to gradation.

I think we've all been guilty of giving our opinions and impressions in absolute terms, but I think you're holding Steve to too high a standard. We often say this developer/dilution/film/lens. etc. is sharper than some others, and we somehow find ways to agree or disagree without ever presenting more proof than an example image at monitor resolution, and without suggesting our claims should not be taken seriously. I think there are many of us here who might not be able to articulate a definition of gradation or tonality, but I think we all recognize the differences when we see them, and it can become tedious to have to qualify everything we say, as if we're publishing a paper, or testifying in court. I think we're all adult enough to understand when someone says "X gives better tonality than Y", that person is giving his opinion, and we can decide how much weight to lend his opinion without suggesting he doesn't know what he's talking about. ironically, I think most contributors to this thread agree on most points, and there's a lot of experience behind the opinions expressed. I'm very grateful for all of you who take the time to share your results, opinions, and theories, even when I disagree, and even when I might seem overly argumentative, please know it is with respect, and good humor.

Peter De Smidt
9-Nov-2010, 22:16
I never said a word about "full-stop".



This subject has been thoroughly discussed on APUG and several other sites by people have expound on their test and testing methods. As far as making claims, you have implied that I stated claims about the effect of developers on film speed. Since that is patently false, I can never take anything you say seriously. I will now view all you posts as comic relief.

Steve

I didn't say anything about your making claims about the effect of developers on film speed. "full-stop" referred to claiming that something is better in general, as opposed to simply holding that something worked better for you.

I didn't attack you. I didn't say you were wrong. All I did was to ask for an explanation of a claim you made, and you refused to do so, and you're obviously defensive about it.

Peter De Smidt
9-Nov-2010, 22:28
<snip>
I think we've all been guilty of giving our opinions and impressions in absolute terms, but I think you're holding Steve to too high a standard.

All he has to do is explain, even a little bit, what he meant when he said that replenished xtol gives better tonality than Xtol used one-shot. One way would be to say how the curve changed. Or he could've said it gave more mid-tone contrast, or _something_. If we knew what his claim was, then we could do some tests and see if we found the same thing. You know, the good ole scientific method thing. The history of photography is full of people making claims about one developer being better than another. In many cases, it turns out that there were problems with the testor's methodology. I'm not saying that's the case here, as I don't know what the claim even is.

Jay DeFehr
10-Nov-2010, 08:49
Peter,

I concede the point. Sometimes I think we borrow language to describe what we see, or believe. We might read somewhere that replenished Xtol improves tonality, and then upon seeing results we like, assume our favorable impression must be based on that "improved tonality". I've been guilty of turning to the literature to explain my impressions, and I don't think it's too serious a crime. I think it's only natural that impressions come first, and explanations later. I think the error is in putting too much weight on our explanations without verifying them experimentally. I don't think everyone with an opinion is compelled to provide experimental support for it, but lacking that, I think we should temper our zeal. I personally regret when I've been too forceful in advancing my own opinions, whether I believed them to be substantiated, or not, and I hope that hasn't been the case here.

IanG
10-Nov-2010, 09:02
All he has to do is explain, even a little bit, what he meant when he said that replenished xtol gives better tonality than Xtol used one-shot. One way would be to say how the curve changed. Or he could've said it gave more mid-tone contrast, or _something_. If we knew what his claim was, then we could do some tests and see if we found the same thing. You know, the good ole scientific method thing. The history of photography is full of people making claims about one developer being better than another. In many cases, it turns out that there were problems with the testor's methodology. I'm not saying that's the case here, as I don't know what the claim even is.

How we perceive tonality in finished print is not just down to the tonal reproduction as measured by film/developer exposure curves. If the grain is finer a print will appear to have smoother tones.

So with a good replenished developer giving finer grain then there can be the appearance of better tonality.

Ian

Jay DeFehr
10-Nov-2010, 11:17
Ian,

I agree. Tonality is not so much a characteristic as an amalgam of characteristics, which is why it's so difficult to quantify, or even discuss, but we know it when we see it!

Peter De Smidt
10-Nov-2010, 12:42
How we perceive tonality in finished print is not just down to the tonal reproduction as measured by film/developer exposure curves. If the grain is finer a print will appear to have smoother tones.

So with a good replenished developer giving finer grain then there can be the appearance of better tonality.

Ian

That's a good point, Ian, although in that case saying that developer* X gives finer grain with a given film than developer Y, when both films are developed to the same contrast, is much more informative than saying that one developer gives better tonality, especially when the latter term isn't explained.

*"Developer" in this case means the whole development process and technique.

Jay DeFehr
10-Nov-2010, 15:38
Peter,

Comments about grain are not interchangeable with comments about tonality. In other words, saying, "developer* X gives finer grain with a given film than developer Y, when both films are developed to the same contrast", tells us little about tonality. You seem to suggest we shouldn't talk about tonality/gradation at all, because we can't quantify it. I think you place far too much importance on film curves. Characteristic curves are useful, but very crude graphical representations of the film/development relationship. A visual evaluation of a print tells us infinitely more about that relationship than any graph ever could, but the graph simplifies and deals in quantities, not qualities, and it's easier to compare quantities than qualities. That shouldn't be taken to mean quantities are more important than qualities, or that qualities should be ignored because they're inconvenient to compare objectively. We discuss and debate endlessly characteristics like grain and sharpness, even though few, if any of us are actually able to quantify our results. No one blinks when someone says Rodinal produces more grain than D-76, I suspect because it's been written so many times, and numbers have been published to support the contention. Who among us can say with any authority Rodinal really does produce more grain than D-76? How would we quantify it? At best, we could present images showing the differences, subject to all the experimental conditions under which the samples were made. The same is true of sharpness. In fact, the only values we amateurs can normally calculate are contrast and film speed, and even then we can only approximate the standards. I would argue that tonality, or gradation, whichever term one prefers, is the most important element in the relative technical success of an image, leaving artistic considerations aside. I think we discuss it so infrequently because no experts publish gradation values we can compare.

However, I also think we who speak about gradation or tonality would be wise to remember our impressions are our own, and might not transfer to other viewers. I think it's perfectly valid and proper to write, "I use Xtol replenished for the improved tonality over diluted Xtol", because it can only be an opinion. When we recommend others should use Xtol replenished because it produces better tonality than diluted, I think we're compelled to back that recommendation up, because we're suggesting it's an objective fact. How we back it up need not be by some empirical evidence, in my opinion. I think it's enough to give our impressions, and perhaps provide an example. How much weight our recommendation is given is probably more closely related to our reputations and experience than to our evidence, anyway.

Sirius Glass
10-Nov-2010, 15:54
Well, cost is certainly an advantage in some situations. I"m still not sure what you meant by "better tonality," though. How does replenished xtol change the characteristic curve of, say, TMY, as compared to the developing the film in one shot Xtol?

I have used very little TMY. I shoot Tri-X most of the time for 35mm and 6x6, and I only started using Iflord HP5+ because I cannot get 400 Tri-X in 4"x5" [yes I know that it is not exactly 4"x5", but that is what it is referred to as being. Read: I am not interested in flame wars on trivia. I come here to learn, get others opinions, and try new things.]

I do not plot characteristic curves, but similar photographs processed the same way showed smoother tonality and finer grain with replenished XTOL versus non-replenished XTOL.

A couple of years ago I tested stock XTOL versus 1:1 XTOL one shot and I preferred the stock more. The exact reasons I do not remember any longer.

I do not get into exhaustive testing. I try something for several rolls of film and compare that to earlier work. The I go with the results that I like better.

No, I do not have a way to measure density; nor do I wish to play "Junior Ansel wanna be".

Steve

Peter De Smidt
11-Nov-2010, 08:36
Peter,

Comments about grain are not interchangeable with comments about tonality.

I agree, but the change in tonality of a print with finer grain is fairly easy to predict. To see this, make a series of prints at different enlargements from the same negative and compare their tonality.


You seem to suggest we shouldn't talk about tonality/gradation at all, because we can't quantify it.

Not at all, but it is an ambiguous term. When Steve used it, I simply didn't know what he meant. I shouldn't have said anything about change of curve shape, although that would represent a change in tonality, and I never meant to imply that changes in tonality only result from changes in curve shape. All I was looking for was some further explanation, which could've been nothing more than an attempt to describe the phenomenological differences that lead to Steve's claim.


A visual evaluation of a print tells us infinitely more about that relationship than any graph ever could, but the graph simplifies and deals in quantities, not qualities, and it's easier to compare quantities than qualities.

Right, but then it shouldn't be that hard to put some of that "infinitely more" into words.


No one blinks when someone says Rodinal produces more grain than D-76, I suspect because it's been written so many times, and numbers have been published to support the contention.

Right, but that's because the phrase "smaller grain" is less ambiguous than "better tonality."


How we back it up need not be by some empirical evidence, in my opinion. I think it's enough to give our impressions, and perhaps provide an example.

Agreed. That would've been enough for me.

All of this said, it should be ok to ask for an explanation when someone makes a claim in a public forum. Being questioned does not entail being denigrated.

Jay DeFehr
11-Nov-2010, 09:47
Peter,

I agree on all counts. I'm sorry if I seemed critical; my intention was to find common ground, and I think we have. Thank you for an interesting and enlightening discussion.