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Jobo atl3
Hello, i am looking for an jobo ATL3 manual.
Can somebody help me ? Thanks, Joe. |
#2
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I think there is a site called Butkus (or something similar) which has instruction manuals on line which can be down loaded.
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#3
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Pyro Developers Question.
"Darkroom User" wrote in message news Is there any advantage or quality difference to using a pyro developer instead of a normal developer such as D-76 or Xtol? Developers like Pyrocat-HD, WD2D and PMK get mentioned a lot on the internet photo sites. -- Darkroom User Boy, have you opened a can of worms he-) Pyro was the first organic developer discovered and applied c.1860. Previous developers were inorganic and nowhere near as efficient. Pyro remained a favorite for the next fifty years but was eventually supplanted by developers employing a combination of Metol (AKA Kodak Elon and a bunch of other names) and hydroquinone. These two in combination can make a very wide varity of developers. Pyro, in the right sort of formula produces a stain image along with the silver one. The stain image is usually a yellow or greenish brown. It increases the effective printing density when the printing material is sensitive only to blue light. Pyro became popular when it was discovered that the stain image would act as a contrast mask when films were printed on variable contrast paper, tending to lower the contrast of the highlights. This was considered desirable because some modern fils, tabular grain ones like Kodak T-max for instance, can produce extremely high maximum densities. Because the traditional Pyro developers tended to be somewhat grainy some more modern ones were devised. PMK in particular has become popular. However there may be problems with it, for one thing the books on photographic chemistry warn that borax is not compatible with Pyro and should not be used in Pyro developers. PMK uses "Kodalk", Kodak's trade name for sodium tetraborate, a borax compound. I've seen several explanations of why this is OK in this particular formula. Traditional Pyro developers are mixed from two or three stock solutions. This is because the most Pyro developers are vulnerable to oxidation from the air and are not long lived when mixed. When Pyro was the principle developing agent a great deal of work was put into devising _non-staining_ formulas. This is because the effect of the stain on printing density is not easily predictable and it was found in motion picture practice that obtaining consistent results was difficult. When D-76 was introduced in 1926 it very rapidly displaced all other developers for motion picture negative processing. This was partly because it produced fine grain negatives but also because it was more consistent and controlable than previously used developers. Pyro has a couple of advantages especially for tray use: while it is itself rapidly oxidized it does not produce aerial fog, secondly, its a fairly good desensitizer so is advantageous when developing by inspection. The short life was addressed in some two part forumulas which included Metol. In these developers the Metol is present mainly to preserve the Pyro although it also functions as a developing agent. Kodak D-7 is an example. The three part developer, often called ABC developer, evolved over the years to the point where the published formulas were all the same. Kodak D-1 is a classical ABC developer. These are still quite satisfactory but are probably a bit grainy for 35mm film. Some early formulas used acetone as an intermediate for generating carbonate (actually hydroxide) in solution. Because the acetone is volitile these developers tend to be inconsistent and are the main reason that Pyro got the reputation for being inconsistent. The later formulas using sodium carbonate are much more satisfactory but one still has the problem of determining actual printing density and contrast due to the stain image. BTW, the stain is composed of a humic acid pigment, not a dye, and is probably more permanent than the silver image. Pyro will also work as a warm tone print developer but the color may not always be a desirable one. I collected a bunch of Pyro formulas which someone kindly posted to their web site. It appears as a PDF at: http://www.nonmonotonic.net/Photochemistry/Richard%20Knoppow/Pyro_Developers.pdf There are some good articles on Pyro developers on the web: http://unblinkingeye.com/Articles/PCat/pcat.html http://www.jackspcs.com/pmk.htm A Google search for Pyro Film Developers will find lots more. -- -- Richard Knoppow Los Angeles, CA, USA |
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Pyro Developers Question.
IanG wrote (in part):
Yes there can be advantages and an increase in quality how much depends on the way you work and the developer you choose. Pyrocat HD gives finer grain, better sharpness and more tonality than D76, What does "more tonality" mean? I cannot believe it means a greater dynamic range, because films, with very few exceptions these days, have way more dynamic range than can be printed onto photographic papers. While I no longer use D-76, it is certainly a fine-enough grain developer for 4x5 negatives at sizes up to 16x20, I would say. And it is certainly well capable of getting a density of 2.0 or greater from the films with which I am familiar. Now it may well produce a slightly different curve shape, though that is mostly determined by the design of the film. And some people obviously like different curve shapes from others. I prefer short toe curve shape, where most people seem to prefer a longer toe than I do. The only disadvantage of short toe, in my opinion, is that if you underexpose, it is just not there. So if you pop away on street corners in rapidly changing conditions, Garry Winogrand style, you may prefer a longer toe than I do. I believe he mostly used Tri-X in his Leicas. although originally designed for LF negatives it's also used for 35mm &120 negatives. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey http://counter.li.org ^^-^^ 13:05:01 up 13 days, 15:57, 4 users, load average: 4.42, 4.57, 4.56 |
#5
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Pyro Developers Question.
I've settled on PyroCat-MC as my main developer, especially with
medium format and this combo is very nice with HP5+. I've been a darkroom rat for 40+ years and always maintained some "go-to" combinations when things needed to be predictable and absolutely give usable results. I also played with many films and developers because it kept my interest and imagination stirred up. As I've gotten older and tinker less, I've appreciated the PyroCat variants because of 3 primary reasons: 1. Superb highlight control.... It virtually eliminates clipping and allows me to have great shadow detail and not fear blown highlights. Most films behave predictably at 1/2 box speed as a great starting point and exhibit this basic behavior. 2. Great skin tones. People pictures just seem to print themselves with a beautiful tone spread that gives a 3D effect and depth to faces. Its sharpness and edge effects make eyelashes pop but somehow is also kind to crows' feet, etc. 3. It solved most of my scanning headaches. The tonal range depicted and smooth grain characteristics are especially compatible with scanner's rendition with very little of that grain scatter appearance. The edge effects aid in adding an apparent sharpness that translates well in the digital process. Over the years, I've had good success and a good understanding of most of Ilford's films, Fuji and many of Kodak's. I started with D-76 and still respect it as a great soup that one could happily use forever and give up very little to anything else in general duties. FG-7 was a favorite for many years and I also enjoyed DDX following that. XTOL and the new TMY-2 seem made for each other, too. I only mention these details so you don't think I'm a Pyro fanatic who's been to the mountaintop! The process is also easy and streamlined... I use a 1 minute initial slow inversions cycle, followed by 1 gentle inversion per minute (seems to add a bit of edge effect without getting exaggerated). Follow with a double water rinse (no stop bath) and then fixing in TF-4. Following washing and a drop or 2 of wetting agents, they also seem to sheet off and dry spot free, too. Some films show some emulsion expansion (sort of a frosty look with bright back light) and some show an etching/raised effect on the emulsion side but they seem to settle down after drying. I wish someone would have promoted giving it a try earlier in my darkroom escapades. I would encourage giving it a shot. A neutral or alkaline fixer can aid in keeping the stain effect consistent with Pyro (they're effective and pleasant to use anyway). |
#6
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Pyro Developers Question.
"Jean-David Beyer" wrote
What does "more tonality" mean? Nothing. "Tonality" as applied to photography and as near as I can tell means the writer, using developer X and film Y, made some photos he liked . "More Tonality" means he "more liked" his photos. "Tonality" is a word that should be removed from the language. We don't have "colorality" or "tastality" and have never missed them. I think. I hope. Better check. Oh dear, "tastality" comes up with 14 hits, "colorality" 47. Thankfully used in a mocking context ... I think we can say that negatives developed in Pyro have more "Pyrality" and leave it at that. -- Nicholas O. Lindan, Cleveland, Ohio Darkroom Automation: F-Stop Timers, Enlarging Meters http://www.darkroomautomation.com/da-main.htm n o lindan at ix dot netcom dot com |
#7
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Hi there,
I asked this question about pyro developers on the photobanter website in a separate thread. For some reason, it seems to have got merged with the thread about a Jobo atl3. I am not sure how that happened (sorry). This is where I asked about pyro. http://www.photobanter.com/showthread.php?t=114087 Quote:
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#8
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Pyro Developers Question.
"Darkroom User" wrote in message news IanG;886420 Wrote: PYROCAT HD GIVES FINER GRAIN, BETTER SHARPNESS AND MORE TONALITY THAN D76, ALTHOUGH ORIGINALLY DESIGNED FOR LF NEGATIVES IT'S ALSO USED FOR 35MM &120 NEGATIVES. In addition the negatives are extremely easy to print from, with excellent highlights and shadow detail. It's also a better developer for making negatives for Alt processes. Ian If it gives finer grain as well as better sharpness than D76, then it must be good. Will I actually see these differences with FP4 Plus and T-Max 400? What dilution and times for the small Paterson-tanks? -- Darkroom User Well, finer grain is open to the question of how that was determined. Lots of developers yield finer grain than D-76, some modern ones, notably Xtol, also deliver somewhat higher speed but most fine grain developers loose some speed. Pyrochatichin, which is related to pyrogallic acid but is a different chemical can be used in developers which have strong edge/border effects. This gives the illusion of sharpness. There is another effect of certain developers containing pyro and its relatives, that is that it tans the gelatin image wise. The variation of index of refraction after development can lead to a similar kind of edge effect which is visualized as "acutance" or the impression of sharpness. Note that "acutance" is a Kodak term for this illusion. High acutance films do not, in general, increase resolution, in fact they may reduce it. However, where one is working with small negatives acutance effects will partially compensate for the lack of sharpness in the lenses. Note also that border/edge effects, and hense acutance, is of a fixed scale so that its effect is dependant on the magnification of the image on viewing. It can have a quite significant effect on 35mm negatives but will be virtually invisible on a 4x5. Graininess also gives the illusion of sharpness. A somewhat blurry image when overlayed with a sharp grain pattern will appear to be sharp, at least at first. -- Richard Knoppow Los Angeles, CA, USA |
#9
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Pyro Developers Question.
"Lew" wrote in message ... What about film speed? Are there any fine grain, staining developers mixed with phenodone, for example, to give the speed increase we experience with xtol? I don't know. Imagewise staining is produced by some phenol type developers as is imagewise tanning. Pyrogallic acid and Pyrochatichin (there are other spellings) are formost among the staining developers but hydroquinone can cause imagewise tanning without the staining. Pyro has been mixed with other developing agents, particularly Metol, but that was done beause the two tend to preserve each other and extend the life of the developer. Curiously much of the reseach done on Pyro developers before they were pretty much supplanted by M-H types was to devise non-staining developers. The reason is that the stain image affects the printing density in a way that varies with the spectrum of the printing illumination and with the spectral sensitivity of the printing material, plus it can be difficult to measure because the densitometer used must match the spectral sensitivity of the printing material. All is much easier when the image is neutral. You can get some idea of the increase in effective density for blue-sensitive materials by looking at the negative though a blue filter. Its also possible to bleach out the silver image which leaves only the stain image. That is one way of determining the effectiveness of a developer in forming a stain image. The effect desired by most workers using current materials is the self-masking effect of the stain image when used with variable contrast materials. It tends to lower the contrast of the highlights flattening out the very high contrast produced by some modern films. In effect it creates a shoulder on the film characteristic. Might or might not be desirable and may not be much of an effect on some material. Grain is affected by many variables: the activity of the developer is one, generally less active developers are less grainy; another factor is the pH of the developer, higher pH (more alkaline) tends to produce coarser grain; the presense of halide solvents affects grain somewhat but not for the reasons popularly supposed. The solvent, sulfite in most developrs, does not "etch away the grains" but rather affects the way the crystals grow as they are developed. Up to a certain point the presense of a solvent will increase film speed because it makes more development centers available to the developer. This is one reason that D-76 has become the reference standard for film speed. When more solvent is present, or a stronger solvent such as sodium thiocyanate, is used the film speed goes back down because the solvent can destroy some of the latent image centers. The total range of speed variation from "normal" type developers is about 3/4 stop more to 3/4 stop less than D-76. Some Phenidone developers, notably Xtol, T-Max RS, Microphen, as examples, increase speed about 3/4 stop. Some very fine grain developers such as Perceptol and Microdol-X decrease it about 3/4 stop. About the only developers which loose more speed than this are the old fashioned paraphenylenediamine super fine gain developers. A pure PPD developer (with no other agent added) can loose as much as 5 stops! These developers can also produce severe dichroic fog on modern films and do not, for the most part, produce any finer grain than Perceptol or Microdol-X In general, film speed and fine grain are not compatible. Probably the best compromise is Xtol which yields slightly finer grain and slightly higher speed than D-76 along with good sharpness and good tonal rendition. Whatever reliability problems it had in the past seem to have been cured. -- Richard Knoppow Los Angeles, CA, USA |
#10
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Pyro Developers Question.
In article ,
Darkroom User wrote: IanG;886420 Wrote: PYROCAT HD GIVES FINER GRAIN, BETTER SHARPNESS AND MORE TONALITY THAN D76, ALTHOUGH ORIGINALLY DESIGNED FOR LF NEGATIVES IT'S ALSO USED FOR 35MM &120 NEGATIVES. If it gives finer grain as well as better sharpness than D76, then it must be good. It also gives world peace and free beer. You can be sure it is excellent. -- Thor Lancelot Simon "All of my opinions are consistent, but I cannot present them all at once." -Jean-Jacques Rousseau, On The Social Contract |
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