Gast
Has anyone here tried the new Moersch negative developer yet?
What have your experiences been like, particularly—not with T-Kristall films, of course, but with Trix or Effke? And what exactly is a staining developer, and what is it used for???
Best regards
Martin
Gast
Hello!
I haven’t tried Tanol yet, but I have used Pyrocat HD – also a ‘staining (or ‘tanning’) developer’; in German these are called ‘tanning developers’; they are developers based on pyrogallol or catechol with a low sodium sulphite content; typically, part of the negative density is achieved through the ‘stain’, i.e. a colouring of the film gelatine layer – depending on the developer, this can range from greenish to brownish. Result: less grain in the highlights, very high sharpness, better/smoother reproduction of bright mid-tones and highlights (good for foggy scenes or similar), and with developers that tend to colour greenish, lower contrast in the highlights with multigrade paper (thereby providing very good contrast compensation); some of these developers are used by large-format photographers who wish to produce both contact prints on ‘standard’ silver gelatine paper and platinum prints (or other alternative processes requiring high-contrast negatives).
The best-known pyrogallol-based ‘staining developers’ are PMK (Pyrogallol-Metol-Kodalk), ABC Pyro and Rollo Pyro; the Brenz-catechin-based developers include the Windisch developers, DiXactol and, of course, Pyrocat HD; I’d also like to know what’s in Moersch Tanol....
By the way: I tested Pyrocat HD against Rodinal and a homemade formula for a Metol-2 bath developer by Barry Thornton – whilst Pyrocat HD is quite sharp (in terms of acutance and resolution), the other two are slightly sharper; where Pyrocat HD really shines is in its very smooth rendering of highlights, I think Tanol will probably behave in a similar way....
Gast
fotohuisrovo
We’ve just developed an FP4+ at ISO 80: it’s off to Moersch Tanol. We’re really looking forward to seeing the results too. :D
We’ll be in touch.
Best regards,
Fotohuis RoVo
Robert Vonk
Gast
:D
The first roll of FP4+ (roll film) at ISO 80 has been processed in Tanol. Great result. (5+5+500 ml at 22°C for 13:30 mins.)
Everything looks quite good; perhaps ISO 64 would have been even better, but I’ll need to measure everything precisely at the end of this week (using a densitometer), as I have another wedding shoot tomorrow.
I’ve also shot another roll of FP4+ film at ISO 64 with the Bergisches Fotoverein (Wuppertal). That will be my second attempt.
Best regards,
Robert
WolfgangMoersch
Hello Robert,
One of the testers achieves the rated sensitivity with Kodak and Ilford films. As our results have been almost identical with other developers for years, I had to get to the bottom of this. It eventually turned out that the differences are due to the water used to dilute the developer. That may sound a bit far-fetched at first, but tap water differs both in terms of its ‘salt content’ and its pH value. With such a high dilution of 1+50, water quality plays a significant role; the pH differences alone between identical solutions were as much as 0.30, and that is bound to have an effect. For me, using demineralised water results in significantly greater speed than indicated in the table. Perhaps you could check this out sometime? I’d be very interested to know what values you get with Ravensteiner water.
Regards
fotohuisrovo
Hello Wolfgang,
Yes, that could well be the case, as the buffering effect can shift slightly. Here, we get our water from the ground via W.O.B. (Waterleidingbedrijf Oost Brabant), but not – as is partly the case in Rotterdam, for example – from the Rhine and/or Meuse via Sparwasser.
That means hard water: DH (German hardness) fluctuates between 13 and 14, so there are a lot of carbonates in the water. The pH is bound to change as a result.
I’ll repeat the tests on the ISO 80, but this time using deionised water in the Tanol. The conditions will be exactly the same. (I’ve done it in the TAS from Heiland).
Next up this evening is the second FP4+ test, carried out at iso 64 in the Tanol using Ravenstein tap water. We’ll report back. Is there enough EDTA in the Tanol to capture the metal ions?
Best regards from Holland,
Fotohuis RoVo
Robert Vonk
PS. By the way, do I still need to book a holiday home for you somewhere round here? Your wife hasn’t got in touch about it again. :D
fotohuisrovo
Yes, the results are much better now and reproducible. The issue with the buffer shifting is a critical one. We’ve now simply used demineralised water for the preparation.
Best regards,
Robert
MKL
Hello,
According to the description, the Tanol developer should colour the emulsion green or yellow. In the case of variable contrast papers, this staining then has the effect of flattening the gradation in the highlights. However, it also has an effect on fixed-gradation papers, which, as is well known, are insensitive to green. With fixed-gradation papers, a pronounced edge effect becomes apparent. In practice, this means completely different results when printing!
Whether it is an advantage that the highlights on variable contrast paper become muddied and do not appear as brilliant as usual is certainly a matter of opinion! I prefer to conduct the development of my films in a tailored manner, thereby avoiding overexposed highlights – I am not particularly keen on smooth highlights.
The well-known Pyro Staining developer was originally used for the opposite purpose, namely to achieve a stepped gradient in the highlights or a pronounced edge effect when printing on fixed-grade paper!
Best regards
Michael
aXL
Hi, Michael.
Thanks! :)
Finally, someone who can offer specific and helpful advice on pyrotechnics!
I’ll briefly describe what I want to do and what I’m hoping for – perhaps you could give me a bit more detail on whether it’s worth the effort:
Two subjects: nudes and landscapes. The former in the studio with a flash setup, the latter naturally not. ;)
Film: efke 13x18 100 ASA and 9x12 100 ASA
Development: So far, manual in a flat film tank.
Enlarger: Condenser units with Ilford filter sheets
Paper: Maco Expo G and Expo RF (fixed-grade, actually efke), will probably be replaced by Classic or Kentmere soon.
My questions:
First and foremost, the paper: So far, I’ve been using fixed-grade baryta paper and variable-contrast PE paper. My understanding of the effects of negative discolouration was that I could selectively re-expose the highlights (0 filter) and shadows (5 filter) using the MG filter. The principle is as follows: blue light (5) is blocked by the green areas in the negative and affects almost exclusively the shadows in the print. The highlights in the print respond much more strongly to green light (0) anyway (cf. split exposure), which is further enhanced by the colouring of the negative.
Voilà – targeted re-exposure of the highlights or shadows without masks or dodging! Or not? :rolleyes:
Otherwise, I wouldn’t know what advantages a flattening of the gradient in the highlights has, because in landscape photography it’s not uncommon to re-expose the sky with a 5-stop gradient to achieve dramatic light and crispness. I find it hard to imagine how the effect of flattening the highlights would work in portraits and nudes. B)
And now you come along and say that the tinted negatives produce crisper highlights on fixed-grade papers. Can you imagine how wide my eyes are going to get?! :o
On the working method: My tank only holds 4x5" and 9x12. I don’t have a suitable tank for my favourite format, 13x18. But pyro development in an open tray in complete darkness? I don’t know... :huh:
Should I actually buy a CPA processor, which, as we all know, still costs a fortune? Is the constant rotation an advantage for pyrogallol development, does it have disadvantages, or does it not matter?
Thanks in advance!
Axel
MKL
Hello Axel,
First of all, I must say that I haven’t worked with pyrogallol yet – it’s too toxic for me! So my knowledge is limited to examples I’ve seen and pure theory.
Fixed-grade paper:
The green tint of the silver layer causes the light that is still transmitted in the highlights to be filtered green, thereby shifting it towards the insensitive end of the spectrum. This makes the highlights appear steeper (more brilliant). Additionally, this effect makes the highlights stand out more clearly from the shadows and creates a stronger effect at the edges.
With variable contrast paper, the exact opposite is the case, as this reacts to green light with a soft gradient.
Your approach using manual split-grade works quite well even without a staining developer. However, with difficult subject contrasts, there is no getting round the need for re-exposure or dodging. This is not usually a problem with studio flash portraits, but it does become an issue later on with landscapes.
Just a quick note on filters: Yellow filters through green and red, though only green is of interest for MG papers.
Magenta passes through red and blue, though only blue matters here. This is what gives rise to the effect of the green silver layer. In the shadows, which are significantly influenced by high gradients (blue light or magenta filters), nothing changes, but in the highlights, which are blackened more quickly by low gradients, the differentiation suffers.
For nudes, I would use a fast film (25–50 ASA) to break down the moderate contrasts of, say, a SoBo. For landscapes, measure the scene contrast and adjust the exposure and development accordingly – especially with large format.
Best regards
Michael
Gast
Well, hello,
There seems to be a misunderstanding here?!
Of course the curve gets steeper with PMK, Pyrocat HD, Dixactol and Tanol. Thousands of PMK users must be a bit daft if they’re willing to put up with washed-out highlights.
Of course, you can adjust the development with any developer to avoid ‘blown-out highlights’.
And of course, one can argue whether ‘staining’ developers offer any advantages at all.
Firstly, it should be clear that these developers do not deposit the emulsion (evenly); instead, a colorant forms in proportion to the silver density, making the curve steeper. Black-and-white densitometers cannot measure this secondary density, so the dynamic range is on average approx. 0.25 logD higher than the measurement.
What are the advantages?
All developers of this type produce high acutance – if allowed to. High agitation, such as in the Ratation, has a negative effect on the impression of sharpness.
All developers of this type have a low sulphite content, which is good for sharply defined grain, as is also the case with other low-sulphite developers (Rodinal). A sharp grain is not always desirable; particularly at higher densities, this can become unpleasant even with normal development, let alone with the much-loved pushing technique. As silver and dye densities add together and the stain is not present as a royal body, these developers therefore have the advantage of producing a rather inconspicuous royal body despite their high sharpness.
The negative colour with pyrogallol developers is greenish and significantly more noticeable than with pyrocatechol, which tends more towards a brownish hue. Base and fog are higher with pyrogallol, but this is not a major disadvantage as the film is fully exposed.
Now to Tanol. If you measure the negative in projection, for example with the Heiland, and it shows a gradient of 3, then a gradient of 2 is correct.
If the film/developer combination is set even approximately correctly, you will find yourself between gradients 1.5 and 3.5 on a roll film with slightly varying exposure contrasts.
If one or two negatives on a roll of film have turned out too steep due to ‘inappropriate development’, this does not mean that the highlights are ‘closed’ and cannot be reproduced on paper.
If the highlight densities are too high with conventional development, partial adjustments often become difficult.
If, for example, an overly dark sky needs to be re-exposed, fine (still discernible in the negative) gradations are lost. A muddy, undifferentiated grey can only be avoided, if at all, with extra-hard filtering. With equal densities from stain and silver, this is much easier because the grain is more open.
An edge effect is by no means always positive. An edge that is too strongly emphasised can enhance the impression of sharpness at 24x30, but at 50x60 it can become unpleasantly conspicuous.
With papers of approximately the same quality, the edge effect is largely unaffected by whether it meets a fixed or variable gradation at the bottom.
So much for today’s words....
May all ambiguities be dispelled.
WolfgangMoersch
Apologies for the anonymous guest post – I wasn't logged in.
Wolfgang Moersch
WolfgangMoersch
Is there enough EDTA in the Tanol to chelate the metal ions?
Hello Robert,
Hard to say. Strictly speaking, a quarter of the developer consists of complexing agents; you can’t really fit much more in there. How would that even work with 20ml of concentrate to 1000ml of water? The developer and alkali have to fit in somewhere too <_<
MKL
Hello Mr Moersch,
I can’t quite follow your point. With PMK, for example, Barry Thornton has demonstrated precisely this effect of flattened gradation. Surely PMK users aren’t daft; they simply use fixed-grade paper!
As you’ve already written, the relatively coarse grain is effectively softened by the proportional insertion of the emulsion and is no longer as prominent. Viewed from the negative’s perspective, the effect is therefore the separation of the negative densities. Nevertheless, the insertion of the emulsion filters the light towards yellow or green, and this in turn causes a flattening of the gradation on MG paper, thereby negating the intended effect.
Can you explain to me why the measurement using split grades doesn’t work? I’ve always thought that density is density.
Have you ever tried this? Comparing fixed-grade paper grade 2 with MG paper grade 2?
Best regards,
Michael
Gast
Measurements taken with the Splitgarde are less accurate because the green/yellow/brown light caused by the stain may not have the same density for the sensor as it does for the paper. There are slight discrepancies here. However, it is certainly sufficient for a decent working print, at least for BT’s developers, and anyone using these (or Tanol, PMK etc.) will need to make further adjustments in most cases anyway.
