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Photo Forum / Film Photography / Darkroom / March 2004PQ Stain
Patrick, I did some prints with the new PQ staining developer last night and everything you said was correct. The prints print more contrasty than they appear by eye. It's also very, very active (10% Q and 0.25gms Pheni in 100mls of Propylene Glycol) develops in Borax Carbonate in about 5mins for normal contrast with APx 100. Anyway the thing I am writing about is the amazing tones you get with this stuff! The grain is ok (not as fine as in the p-Aminophenol/Vit C Propylene Glycol) but I cant get over those tones, a 12x16in print from 35mm looks like medium format quality~! Thanks again, Nicholas > Patrick, > I did some prints with the new PQ staining developer last night and [quoted text clipped - 8 lines] > Thanks again, > Nicholas Woops, that was supposed to be a private email! Dooh! Never mind at least it went to the right group - Ha. Mr. Nicholas The FBI, CIA, Mossad and KGB all together are very much interested in your covert activities. Would you pls explain (under oath) why Pglicol and not alcohol? >> Patrick, >> I did some prints with the new PQ staining developer last night and [quoted text clipped - 10 lines] > Woops, that was supposed to be a private email! Dooh! Never mind at > least it went to the right group - Ha. > Mr. Nicholas > [quoted text clipped - 18 lines] >>Woops, that was supposed to be a private email! Dooh! Never mind at >>least it went to the right group - Ha. Using Propylene Glycol assures me that the developing agents will not ionise. The PQ staining developer mixes clear. Iso is easier to prepare but AFAIK does ionise developing agents eventually, perhaps because it is hydroscopic(?). Glycerine shouldn't ionise, but have you ever tried using that gloopy stuff? I have, and its a PIA to deal with. Obviously because there are no traditional "preservatives" in these developers it is important to factor in the longevity of the mixture in. Thanks, Nicholas Jorge > Using Propylene Glycol assures me that the developing agents will not > ionise. The PQ staining developer mixes clear. Iso is easier to prepare [quoted text clipped - 3 lines] > because there are no traditional "preservatives" in these developers it > is important to factor in the longevity of the mixture in. > Patrick, > I did some prints with the new PQ staining developer last night and [quoted text clipped - 7 lines] > quality~! > Thanks again, Nicholas, You may as well tell everyone what dilution and amounts of borax and carbonate you used. I just got and signed the contract for the article in Photo Techniques next issue, but I didn't describe the use of borax-carbonate. Makes me feel good that you like the results. We have been keeping the wrong thing away from developer in our efforts to preserve stock solutions. We worry about air, when we should be worrying about water. Keep the water away until the last minute. Dissolve hydroquinone or ascorbic acid or catechol or pyrogallol and/or phenidone in propylene glycol for the stock. I find it necessary to heat the mixture in order to dissolve the dry chemicals and to drive out water that may be in the glycol. This won't work with most alcohols which would boil away before the water. There is a method of dehydrating alcohol with anhydrous copper sulphate, but who wants to take a chance on having traces of copper in the developer? > Nicholas, > > You may as well tell everyone what dilution and amounts of borax and > carbonate you used. I just got and signed the contract for the article > in Photo Techniques next issue, but I didn't describe the use of > borax-carbonate. Makes me feel good that you like the results. Really, it is an outstanding developer in those terms I described before, even the grain is very fine! Compared to the p-Aminophenol version it's difficult to say, Apx 100 is so grain-free in that brew it's hard to see any grain @ 12x16in (the largest size my enlarger normally allows). _Stock_ _Developer_: 10gms (1TBS + 1/4tsp) of Hydroquinone .25gms (1/8tsp) of Phenidone Heated to dissolve in 100mls Propylene Glycol (use a water bath) Dilute 1:50 to make working solution with 4gms of Borax (1tsp) & 5gms of Sodium Carbonate (1tsp) per litre of working solution. 5 1/2 minutes with Apx 100 gave soft-ish looking but contrasty printing negatives. 1min initial agitation, 5 inversions every minute thereafter. I was thinking about the water in the developer issue before when Jorge asked that question why not use another alcohol and remembering that Isopropyl Alc takes on water in the atmosphere is probably one reason that Phenidone dissolved in it goes "off" eventually... I did read Patrick's item a few weeks ago with some skepticism, but this really does sound interesting. I suppose I've been mixing with water for so long that this concept seemed strange. Since your negs look not very contrasty but print with greater than expected contrast, I assume that they are stained like a pyro neg. What is the colour of the neg image? Did you use VC paper? The reason for my asking is as follows: It used to be said the pyro negs gave smooth prints because the stain added to the silver grain (and gaps between grains), leading to good density with minimal development which of course leads to minimal grain. This was with graded papers. Nowadays with VC papers it is being said that pyro gives a built-in soft filter to control highlights, but the effect is not always desirable, since with VC paper the highlights can look flat with some subjects. Have you used PMK? If so, how would you compare PMK with this new formulation? Did you do a measurement of film speed? I'm no chemist, but the formula of propyl glycol looks like an alcohol. Does it absorb water from the atmosphere? I note that its boiling point is 150degC, well above that of water and other common alcohols. So heating it could drive off water as long as it didn't decompose. The developing agents could also get cooked. How hot can you make it before any such troubles occur? Just what I wanted. Yet another developer to obsess over, just when I thought I had narrowed it down to two. I've used Patrick's vit C Pglicol, some comments: One should heath Pglicol to above 100C - Patrick recommends microwave, to expell all the water. When it cools to 80C, then add the chemicals. My personal feeling re speed is that it shall be good (ISO rating or close) due to phenidone/carbonate+borax alkali (pH equivalent to metaborate). No idea re staining - neve used staining devs. Jorge > I did read Patrick's item a few weeks ago with some skepticism, but > this really does sound interesting. I suppose I've been mixing with [quoted text clipped - 29 lines] > Just what I wanted. Yet another developer to obsess over, just when I > thought I had narrowed it down to two. > I did read Patrick's item a few weeks ago with some skepticism, but > this really does sound interesting. I suppose I've been mixing with [quoted text clipped - 3 lines] > expected contrast, I assume that they are stained like a pyro neg. > What is the colour of the neg image? Brown and stained > Did you use VC paper? No, Forte Fortezo G3 > The reason for my asking is as follows: It used to be said the pyro > negs gave smooth prints because the stain added to the silver grain [quoted text clipped - 4 lines] > not always desirable, since with VC paper the highlights can look flat > with some subjects. I've heard that VC papers can do this as well, but also that the stain (usually) increases the density of the neg more than the colour of the stain decreases it even with VC... > Have you used PMK? If so, how would you compare PMK with this new > formulation? No, I haven't tried PMK, Patrick just emailed me tonight privately saying that he couldn't tell the difference between Catachol and Hydroquinone in Pyrocat-HD and that it is a safer and cheaper what to get what most people like about Pyro developers such as PMK. But perhaps you should ask him exactly what he thinks instead of me paraphrasing him as he has many years of experience with all of these developers. > Did you do a measurement of film speed? No, but compared to the same roll I did in another developer this one seems to have full speed without exaggerated FB+F. > I'm no chemist, Me neither but the formula of propyl glycol looks like an > alcohol. Does it absorb water from the atmosphere? I note that its > boiling point is 150degC, well above that of water and other common > alcohols. So heating it could drive off water as long as it didn't > decompose. The developing agents could also get cooked. How hot can > you make it before any such troubles occur? Its a diol - a double alcohol. It doesn't seem to take on water because if it did it wouldn't last as long as it does. Wonder why then one has to heat it to expel the water as per Jorges comments on Patricks recommendations? > Just what I wanted. Yet another developer to obsess over, just when I > thought I had narrowed it down to two. Me too, I thought the same thing as soon as I developed these frames last night. I was happy with my other developer, but compared to these photos it looks like I've got a new favorite developer and it doesn't have any Vitamin C in it at all! Just a couple of general comments here on Patrick's most recent developers to fill in some details about what Patrick, Nicholas and Jorge have been writing about. Hope you guys don't mind me piping up here to give a "bird's eye" description of this stuff. Many of you know about Patrick's developers from the article posted on the unblinkingeye.com web site. The ones he describes there are based on combinations of ascorbic acid (Vitamin C) and phenidone or metol, dissolved in various alkaline buffers (based on sodium carbonate or borax/lye mixtures). None of his formulas use sodium sulfite, which makes them very unusual in the developer world. Patrick's latest film developers are also based on simple combinations of developing agents and have also been formulated without any sodium sulfite at all. However, lately he has been using propylene glycol as a solvent (instead of water) to make up the stock solutions. The stock solutions don't contain any alkaline component or preservative (other than the Vitamin C itself). Part of the reasoning behind using propylene glycol is that a water-free stock solution inhibits the ionization of developing agents and reduces their tendency to be oxidized by air. The stock solutions won't develop film until they are diluted in water containing sodium carbonate, borax, or both. This is similar to the case of HC-110, another stock solution in a viscous organic solution. Patrick has found that HC-110 syrup (undiluted) does not develop film. Although the propylene glycol has to be heated to get the developing agents into solution, the developing agents don't crystallize out on cooling. Propylene glycol is pretty readily available from chemical suppliers, Photographer's Formulary, and also (pretty inexpensively) at www.chemistrystore.com. It is non-toxic -- used as an environmentally friendly antifreeze and as a base for cosmetic products, etc. It's a viscous liquid and is quite hygroscopic (it absorbs water vapour from the air). However, the amount of water absorbed isn't enough to cause problems. The stock solutions in propylene glycol keep for a very long time. The mixed developers give good film speed and fine grain. I've used the Vitamin C / Phenidone version on HP5 Plus, FP4 Plus, and PanF Plus with good results. The PanF looked especially nice. What Nicholas and Patrick have been discussing here are variants of these developers that contain hydroquinone. Patrick found that hydroquinone acts a staining agent in the absence of sodium sulfite. I don't know too much more about these experiments but they are very promising. The fact that hydroquinone acts differently in this case than it does in (say) D-76 isn't surprising. Hydroquinone is known to react with sodium sulfite in alkaline solutions to form a sulfite addition product. Hope I'm not spewing incorrect info here, Patrick or Nicholas should correct me if I am. Jordan (remove "pants" to reply) > I did read Patrick's item a few weeks ago with some skepticism, but > this really does sound interesting. I suppose I've been mixing with [quoted text clipped - 29 lines] > Just what I wanted. Yet another developer to obsess over, just when I > thought I had narrowed it down to two. Patrick I have easy access to 98%~99% pure ethanol (I believe it's not purified through copper - CaO looks more like it if I remember right). How would that compare to Pglicol in your opinion? Besides, I would mix a stock alkali solution also. Thanks, Jorge > Nicholas, > [quoted text clipped - 14 lines] > who wants to take a chance on having traces of copper in the > developer? > Patrick > [quoted text clipped - 27 lines] > > who wants to take a chance on having traces of copper in the > > developer? When you use a technical grade of propylene glycol, there may be water in it. When I first used heat to dissolve ascorbic acid, nothing much happened until I got the temperature up near 250 F. At that point, the ascorbic acid dissolved with evolution of steam. I was not sure whether or not there was an actual reaction with the ascorbic acid, and am still not. Because the glycol does not ionize the developing agents as water does. there is no noticeable loss of activity. Yes, glycols do take on water from the atmosphere, but not very rapidly and only from the atmosphere in the bottle, which cannot contain very much water. I did a life test of a phenidone-ascorbic acid-glycol developer which will be described in the upcoming article, which showed that after exposure to air of a thin layer of stock solution 100 mm in diameter for 16 days, the stock solution had lost no oomph. This is a rather extreme exposure. I don't know of any stock solution of phenidone and ascorbic acid. My interest was in sulfite-free developers. I have found that fine grain, excellent sharpness and good film speed can be obtained without any sulfite, and not just with ascorbic acid. Adding sulfite may actually increase graininess without increasing acuity. The staining-tanning developers include any that have two or more hydroxyl groups such as catechol, hydroquinone and pyrogallol. The staining is reduced by sulfite. Ordinarilly, sulfite is required for preservation, but not when a glycol or alcohol or even an organic base such as triethanolamine is used as a solvent for the stock solution. After water is added, there is a rather short life, but long enough for stand development if that is your cup of TEA. (Pun intended.) "Patrick Gainer" <pgainer@rtol.net> > When you use a technical grade of propylene glycol, there may be water > in it. When I first used heat to dissolve ascorbic acid, nothing much > happened until I got the temperature up near 250 F. At that point, the > ascorbic acid dissolved with evolution of steam. I was not sure whether > or not there was an actual reaction with the ascorbic acid, and am still > not. Ascorbic acid (vitamin C) is heat labile. I am not sure of the max temp it will stand but do know that boiling water will destroy it. I am afraid when it generated a puff, the acid went poof.  SignatureNicholas O. Lindan, Cleveland, Ohio nolindan@ix.netcom.com Consulting Engineer: Electronics; Informatics; Photonics. > "Patrick Gainer" <pgainer@rtol.net> > [quoted text clipped - 9 lines] > > I am afraid when it generated a puff, the acid went poof. My Merck Index gives a melting point of 190-192C for ascorbic acid with "some decomposition". We may be losing a small part of the ascorbic acid on dissolving it in the hot propylene glycol, but not much. The developer still works just fine. Aqueous solutions of ascorbic acid generally decompose quickly due to aerial oxidation. Destruction of Vitamin C in boiling water is probably just a heat-accelerated version of this. The vitamin C does not ionize in propylene glycol and this probably protects it. Jordan I mixed my PA in Pglicol at some 80C (did not heath the Pglicol above that; it's USP grade) 4 months ago. It's working quite well - as a matter of fact, just developed a test strip to test a recently repaired camera. Jorge Jordan Wosnick <jwosnick@mitpants.edu> wrote in news:4031233e$0$573 $b45e6eb0@senator-bedfellow.mit.edu: > My Merck Index gives a melting point of 190-192C for ascorbic acid with > "some decomposition". We may be losing a small part of the ascorbic acid [quoted text clipped - 7 lines] > > Jordan > > >dissolve ascorbic acid ... 250 F ... evolution of steam > > Ascorbic acid (vitamin C) is heat labile. I am afraid > > when it generated a puff, the acid went poof. > My Merck Index gives a melting point of 190-192C ... Destruction > of Vitamin C in boiling water is probably just a heat-accelerated > [oxidation] Mea Culpa. I am reading the wrong cookbook; Fanny Farmer's rather than Steve Anchell's. Thanks: "Say something stupid -- learn something new." SignatureNicholas O. Lindan, Cleveland, Ohio nolindan@ix.netcom.com Consulting Engineer: Electronics; Informatics; Photonics. > My interest was in sulfite-free developers. WAS? Why such exotic compounds such as brake fluid and antifreeze? At bedrock is the lifespan of at least the stock or concentrate. Why not some other scavenger of oxygen? Perhape an oxalate or even one of those used in preserving pharmaceuticals in water solution. Dan > > My interest was in sulfite-free developers. > > WAS? Why such exotic compounds such as brake fluid and antifreeze? > At bedrock is the lifespan of at least the stock or concentrate. Why > not some other scavenger of oxygen? Perhape an oxalate or even one > of those used in preserving pharmaceuticals in water solution. Dan Is there another one that is cheaper than glycol? Besides, glycols are not scavengers of oxygen. In addition, oxygen is not the only concern. Some developer solutions are unstable even when carefully protected from oxygen. The mere ionization of molecules into parts that can oxidize and parts that can reduce makes possible reactions that you may not want. In order to get the sulfite-free preservation of stock solutions one could use an alcohol, but it is difficult to keep alcohols from becoming 10% water. Pure alcohols are more expensive than glycol. Ethanol, for most of us, is subject to a liquor tax. Besides all that, it makes more interezting reading when I write about using antifreeze or brake fluid in developers. I just had an out of town, 'acquaintance / photographer / accomplished printer', in my darkroom so I could develop a roll of film that he used to test a camera he was thinking of buying... When I swung open the cupboard doors and there stood cans of gas line antifreeze, Red Devil Lye, 20 Mule Team Borax, Arm & Hammer Washing Soda, and Vitamin C powder, he started mumbling, "No way... This is a joke, right? Where's the D-76?"... Funny thing, after the negatives were hanging to dry and we were leaving he was still mumbling, " . . & the goddam negatives look great.. I don't believe this..."... Sorta like the day he found the Santa Claus costume in dad's closet... I'm not sure he will ever be the same... denny "Patrick Gainer" <pgainer@rtol.net> wrote in message Besides all that, it makes more > interezting reading when I write about using antifreeze or brake fluid > in developers. That's part of the fun. My next bottle of ID-62 (paper) will be a concentrate mixed with absolute ethanol (I'm one of the lucky few that can buy this stuff at about US$1 a liter), carbonate+ sulfite added at use time... Jorge > I just had an out of town, 'acquaintance / photographer / accomplished > printer', in my darkroom so I could develop a roll of film that he [quoted text clipped - 14 lines] >> interezting reading when I write about using antifreeze or brake >> fluid in developers. When I was a young <gawd, was I ever that young?> grad student and lab assistant in the qual and quan labs, we had 95% Ethanol on the shelf... Some evenings I/we would take a small beaker of that down the hall and around the corner to the biochem lab where the nursing students had lots of OJ on hand... Now, nursing students in those days tended to be very straight laced and anal compulsive due to the selection process... It was always amazing how relaxed and friendly they became after a few hits of 95% in OJ... denny > That's part of the fun. > My next bottle of ID-62 (paper) will be a concentrate mixed with absolute > ethanol (I'm one of the lucky few that can buy this stuff at about US$1 a > liter), Duh. Why did I decide to become an EE?? (-: Jorge > When I was a young <gawd, was I ever that young?> grad student and lab > assistant in the qual and quan labs, we had 95% Ethanol on the [quoted text clipped - 5 lines] > amazing how relaxed and friendly they became after a few hits of 95% > in OJ... denny > When I was a young <gawd, was I ever that young?> grad student and lab > assistant in the qual and quan labs, we had 95% Ethanol on the shelf... Some [quoted text clipped - 5 lines] > relaxed and friendly they became after a few hits of 95% in OJ... > denny There used to be a guy in my lab (before my time) who would take swigs of the absolute ethanol when the urge struck. Besides being painful going down, the absolute stuff is no good for you -- they dehydrate it by distilling with benzene to break the ethanol/water azeotrope. The same guy would dilute glacial acetic acid in water to make a "refreshing foot soak" in the summertime. Pure craziness. Jordan Jordan Over here they use CaO (or that's what I think my father told me a looong time ago). See: http://journeytoforever.org/biofuel_library/Mariller.html at the end of the article. Jorge > There used to be a guy in my lab (before my time) who would take swigs > of the absolute ethanol when the urge struck. Besides being painful [quoted text clipped - 4 lines] > > Jordan OK Jordan... Good memories - what an animal your guy was... On the ethanol, yes they use toxic things to remove the water... No, the toxic things are not present in analytic ethanol in significant quantities... I used absolute ethanol (not the 95%) as a solvent for preparing samples of hydrocarbons for the NMR and gas chromatograph machines during research in the early 70's... Had there been more than microscopic traces of benzene in the solvent it would have distorted the results, so I know it was as close to pure as could be had in that period... Don't know about now as I went into clinical medicine 30 years ago... denny "Jordan Wosnick" <jwosnick@mitpants.edu> wrote in , the absolute stuff is no good for you -- they dehydrate it > by distilling with benzene to break the ethanol/water azeotrope. The It's probably just a tactic they use to scare us off the absolute ethanol in any case. I think you could easily get away with a few ppm of benzene undetected in NMR. Not sure about GC though. In addition to the ethanol and acetic acid, this guy did things that endangered the safety of others as well as himself. He wasn't long for the lab. Jordan > OK Jordan... Good memories - what an animal your guy was... > On the ethanol, yes they use toxic things to remove the water... No, the [quoted text clipped - 11 lines] > >>by distilling with benzene to break the ethanol/water azeotrope. The >It's probably just a tactic they use to scare us off the absolute >ethanol in any case. ... feb1904 from Lloyd Erlick, It's definitely a scare tactic. I live downtown in a relatively large city. In other words, I live where the rubbies live. A rubbie is an alcoholic who drinks rubbing alcohol. (Some people attribute the term to a product called Ruby Rouge, which has the reputation of being the cheapest red wine available.) The true rubby requirers alcohol at all times of day or night, and in Ontario liquor sales are tightly controlled. There are all night pharmacies, however, and a half-liter of rubbing alcohol is a lot cheaper than any liquor store product. Price and availability make it irresistible. The learning curve required to get past the ugly scent and flavor must be pretty daunting. Who says drunks can't work hard? In my years downtown I have witnessed many, many people drinking rubbing alcohol. The containers are usually distinctive, and the hoist they are given puts them on full display. I have observed no blind rubbies, however. Blind drunk, maybe, but the familiar warning about never drinking rubbing alcohol because it causes blindness is inoperative in the jurisdiction I live in. Ethanol is pretty cheap to manufacture. To get around the tax issue, it is rendered undrinkable by scent and taste altering additives. Wood alcohol is not used to denature ethanol where I live, because it causes blindness. There are definitely people so addicted to alcohol they would drink ethanol no matter how it is denatured, and they would drink methanol too, if they could get it. As a community we simply protect these addicts from themselves by making methanol very hard to get. The old attitude was 'let them go blind if they're that stupid', but that's a little Draconian for modern thinking. The punishment for being an out of control alcoholic doesn't have to be blindness. We also don't cut off body parts as criminal punishments around here. Then there are the litigation issues if a society (government administration, politicians and bureaucrats making decisions that cost lives and/or sight...) specifically mandates a toxic (blinding) substance for sale to people known to be unable to control their behaviour relative to the substance... Anyway, there are very few blind street drunks, and even the sighted street drunks make up only a miniscule fraction of the general population, although everyone else gets to use their sight to look at them all the time out there. The scare tactic works very well for almost everyone else. Hey, it's after nine in the morning, pass me that bottle of Rouge ... regards, --le _______________________________________ Lloyd Erlick Portraits, 2219 Gerrard Street East, unit #1, Toronto M4E 2C8 Canada. --- voice 416-686-0326 lloyd@the-wire.com http://www.heylloyd.com _______________________________________ >It's probably just a tactic they use to scare us off the absolute >ethanol in any case. ... feb1904 from Lloyd Erlick, It's definitely a scare tactic. I live downtown in a relatively large city. In other words, I live where the rubbies live. A rubbie is an alcoholic who drinks rubbing alcohol. (Some people attribute the term to a product called Ruby Rouge, which has the reputation of being the cheapest red wine available.) The true rubby requirers alcohol at all times of day or night, and in Ontario liquor sales are tightly controlled. There are all night pharmacies, however, and a half-liter of rubbing alcohol is a lot cheaper than any liquor store product. Price and availability make it irresistible. The learning curve required to get past the ugly scent and flavor must be pretty daunting. Who says drunks can't work hard? In my years downtown I have witnessed many, many people drinking rubbing alcohol. The containers are usually distinctive, and the hoist they are given puts them on full display. I have observed no blind rubbies, however. Blind drunk, maybe, but the familiar warning about never drinking rubbing alcohol because it causes blindness is inoperative in the jurisdiction I live in. Ethanol is pretty cheap to manufacture. To get around the tax issue, it is rendered undrinkable by scent and taste altering additives. Wood alcohol is not used to denature ethanol where I live, because it causes blindness. There are definitely people so addicted to alcohol they would drink ethanol no matter how it is denatured, and they would drink methanol too, if they could get it. As a community we simply protect these addicts from themselves by making methanol very hard to get. The old attitude was 'let them go blind if they're that stupid', but that's a little Draconian for modern thinking. The punishment for being an out of control alcoholic doesn't have to be blindness. We also don't cut off body parts as criminal punishments around here. Then there are the litigation issues if a society (government administration, politicians and bureaucrats making decisions that cost lives and/or sight...) specifically mandates a toxic (blinding) substance for sale to people known to be unable to control their behaviour relative to the substance... Anyway, there are very few blind street drunks, and even the sighted street drunks make up only a miniscule fraction of the general population, although everyone else gets to use their sight to look at them all the time out there. The scare tactic works very well for almost everyone else. Hey, it's after nine in the morning, pass me that bottle of Rouge ... regards, --le _______________________________________ Lloyd Erlick Portraits, 2219 Gerrard Street East, unit #1, Toronto M4E 2C8 Canada. --- voice 416-686-0326 lloyd@the-wire.com http://www.heylloyd.com _______________________________________ sorry, I sent my reply twice! --le _______________________________________ Lloyd Erlick Portraits, 2219 Gerrard Street East, unit #1, Toronto M4E 2C8 Canada. --- voice 416-686-0326 lloyd@the-wire.com http://www.heylloyd.com _______________________________________ > > > My interest was in sulfite-free developers. > > WAS? Why such exotic compounds such as brake fluid and antifreeze? > > At bedrock is the lifespan of at least the stock or concentrate. Why > > not some other scavenger of oxygen? Perhape an oxalate or even one > > of those used in preserving pharmaceuticals in water solution. Dan > In order to get the sulfite-free preservation of stock solutions one > could use ... "One could use" as I suggested, perhaps an oxalate or one used in preserving pharmaceuticals in water solution. Finding an oxygen scavenging substitute for a sulfite may or may not be possible. If the scavenger is too powerfull a reducing agent the silver in the emulsion would be totaly reduced by it. I think there is likely a substitute for sulfite, which scavenges oxygen, and is much less expensive than any of the various fluids suggested although I don't know what it would be. Dan > > > > My interest was in sulfite-free developers. > [quoted text clipped - 16 lines] > suggested although I don't know what it would be. > Dan Let me repeat. The glycol is not an oxygen scavenger. An oxygen scavenger in place of sulfite in a water solution will still allow the water to do what it does: ionize molecules. It will not keep those ionized particles from interacting with one another and thus changing the characteristics of the stock solution. Dissolving the solids in a solvent that does not ionize them is about as close as one can come to making a working solution directly from the solids wihout the inconvenience of measuring each one individually. Measuring 0.05 grams of phenidone is a pain and dissolving it in water is another. In fact, all quantities of solids required to make a liter of a very good developer are so small as to make consistent measurement difficult. That is why we resort to stock solutions in the first place, and then complain like the devil when they are unstable. As for expense, a gallon of technical grade propylene glycol can be had for about 16 US dollars + shipping. Using 20 ml for a liter of working strength developer is not very expensive considering you get about 187 liters of developer out of your gallon. The technical grade is good enough, as is technical grade l-ascorbic acid, available at $15/lb from the same source, www.chemistrystore.com Oxygen is not the major culprit, IMHO. It is water, without which the oxygen cannot do its dirty work. If you want an oxygen scavenger, try ascorbic acid in water solution. It will protect sodium sulfite from oxidation, from what I hear. Please consider my foregoing comments not as flaming, but as fatherly advice. Maybe even grandfatherly. I have celebrated my 40th birthday 37 times already. braggert! :) denny "Patrick Gainer" <pgainer@rtol.net> wrote in message . I have celebrated my 40th birthday 37 > times already. RE: Patrick Gainer <pgainer@rtol.net> wrote > > > > > My interest was in sulfite-free developers. > > > > > > WAS? Why such exotic compounds such as brake fluid and antifreeze? > > > > At bedrock is the lifespan of at least the stock or concentrate. Why > > > > not some other scavenger of oxygen? Perhape an oxalate or even one > > > > of those used in preserving pharmaceuticals in water solution. Dan > P. Gainer > > > In order to get the sulfite-free preservation of stock solutions one [quoted text clipped - 8 lines] > > oxygen, and is much less expensive than any of the various fluids > > suggested although I don't know what it would be. Dan > Let me repeat. The glycol is not an oxygen scavenger. An oxygen > scavenger in place of sulfite in a water solution will still allow the > water to do what it does: ionize molecules. It will not keep those > ionized particles from interacting with one another and thus changing > the characteristics of the stock solution. Now it is more clear. That is the reason some developers are two or even three part. That way the "ionized particles" will be kept "from interacting with one another". That is for developer stock solutions kept in water. I suppose if I were to use glycol, developer stock solutions would need be one part only. > Dissolving the solids in a > solvent that does not ionize them is about as close as one can come to [quoted text clipped - 5 lines] > is why we resort to stock solutions in the first place, and then > complain like the devil when they are unstable. I agree. That as well applies to water. Concentrates and stock solutions are the way. > As for expense, a gallon of technical grade propylene glycol can be had > for about 16 US dollars + shipping. Using 20 ml for a liter of working > strength developer is not very expensive considering you get about 187 > liters of developer out of your gallon. The technical grade is good > enough, as is technical grade l-ascorbic acid, available at $15/lb from > the same source, www.chemistrystore.com A gallon of glycol is $16. I pay 79 cents for a gallon of distilled water. > Oxygen is not the major culprit, IMHO. It is water, without which the > oxygen cannot do its dirty work. If you want an oxygen scavenger, try > ascorbic acid in water solution. It will protect sodium sulfite from > oxidation, from what I hear. Ascorbic acid will protect sulfite if the ph is above 5.? . Below that ph 5.? sulfite will preserve the acid. > Please consider my foregoing comments not as flaming, but as fatherly > advice. Maybe even grandfatherly. I have celebrated my 40th birthday 37 > times already. Brotherly. Dan Not so simple. Sulfite will not dissolve for sure, carbonate or borax possibly not (in Pglicol). Jorge > Now it is more clear. That is the reason some developers are two > or even three part. That way the "ionized particles" will be kept > "from interacting with one another". That is for developer stock > solutions kept in water. I suppose if I were to use glycol, > developer stock solutions would need be one part only. > Not so simple. > Sulfite will not dissolve for sure, carbonate or borax possibly not (in [quoted text clipped - 7 lines] > > solutions kept in water. I suppose if I were to use glycol, > > developer stock solutions would need be one part only. You can in fact make a long lasting single PC or PQ stock solution by using triethanolamine as the base and solvent. The PQ will need a tiny bit of sulfite, no more than 1 gram for each gram of hydroquinone, to form the hydroquinone monosulfonate that results from the P-Q synergism. No sulfite is needed for PC. It is a quick and simple matter to add small amounts of chemicals such as sulfite and bromide that do not dissolve in glycol or TEA to the diluting water when making the working solution. I think some amount of bisulfite will dissolve in the TEA by reaction. I won't swear to it. I think most of us would not believe that the grain produced by a sulfite-free developer could be as fine as that from D-76 or XTOL, but it can. > When I first used heat to dissolve ascorbic acid, nothing much > happened until I got the temperature up near 250 F. At that point, the > ascorbic acid dissolved with evolution of steam. Likely it converted to a less hydrated state. Borates do that. As they are heated the ortho becomes the meta and then the tetra. The tetra is the least hydrated. > Because the glycol does not ionize the developing agents as water does. > there is no noticeable loss of activity. Or leaving the water out, (no objection there I'm sure), and a word or two, it could read; "Because the glycol does not ionize the developing agents there is no activity." That is there is no activity in the concentrate or stock solution, I think is correct. Now we put the water in and leave the glycol out. I still see no activity. I've seen no evidence that the usuall developing agents interact with one another in the absense of some other chemicaly active substance. I don't believe water is the culprit. I believe oxygen is to blame for the "loss of activity" you mention. That's an awfully unsurprising conclusion on my part would'nt you say. It's pure conventional wisdom! When all is said and done a "glycol" approach to very long lived entirely sulfite free concentrates or stock solutions, which yield one shot developers, appears to be sound. I'll stick with the low sulfite brewing I've been doing. For ascorbic acid, which I've not used for sometime, bisulfite to insure acidity will do. Dan Ryuji Suzuki states that the iron/ascorbic acid reaction (that kills ascorbic) is very active at low pH and is inactive (IIRC) at pH of 10 or above. That has been my experience with a very short lived ascorbic stock solution with lots of boric acid - it lasted for about one week... See the notes in his site. Jorge > I'll stick with the low sulfite brewing I've been doing. For > ascorbic acid, which I've not used for sometime, bisulfite to > insure acidity will do. > Dan > Ryuji Suzuki states that the iron/ascorbic acid reaction (that kills > ascorbic) is very active at low pH and is inactive (IIRC) at pH of 10 or [quoted text clipped - 9 lines] > > insure acidity will do. > > Dan Ascorbic acid is more acidic than sodium or potassium bisulfite. Ascorbic acid and sodium bisulfite will react to form sodium ascorbate, water and sulfur dioxide. Some part of the sulfur dioxide will escape to the atmosphere (you can tell by the smell) thus weakening the acid. You will wind up with a higher pH than if you had used ascorbic acid alone. How do you explain the fact that after all efforts have been made to exclude oxygen from a distilled water stock solution, and the solution is quite acidic, and the bottle is full, and the solution has not been used even once, the solution changes color and weakens with time? The fact remains that I left a thin layer of glycol-ascorbate-phenidone stock solution exposed to air at room temperature for 16 days. The test I did after 16 days was no different from the test I did on first mixing. I hope you're not worried about toxicity. You will find propylenr glycol in foods, cosmetics, toothpastes, etc. HC110 is the poisonous one. Instructions are, if you spill it on your shoes, destroy or thoroughly launder the shoes. Take it easy, Patrick... There are closed minds on the subject... Lets talk about something really non controversial, like how do we get the highest ASA, fine grain, high accutance, smooth tonality, and high sharpness, from a single developer? denny "Patrick Gainer" <pgainer@rtol.net> wrote in message The fact remains that I left a thin layer of glycol-ascorbate-phenidone stock solution exposed to air at room temperature for 16 days. The test I did after 16 days was no different from the test I did on first mixing. > Take it easy, Patrick... There are closed minds on the subject... Lets talk > about something really non controversial, like how do we get the highest > ASA, fine grain, high accutance, smooth tonality, and high sharpness, from a > single developer? > denny Read my article in Photo Techniques Mar/Apr issue. Use triethanolamine (TEA) as solvent in the stock solution. It is an organic base that doesn't become alkaline until you add water. I cannot find the grain in a 20X enlargement without a loupe. If you want the simplest possible, use pyrogallol dissolved in TEA. It produces a stained image of very good quality. Patrick According to Bill Troop, TEA is an halide solvent (besides an alkali). Jorge > Read my article in Photo Techniques Mar/Apr issue. Use triethanolamine > (TEA) as solvent in the stock solution. It is an organic base that [quoted text clipped - 3 lines] > If you want the simplest possible, use pyrogallol dissolved in TEA. It > produces a stained image of very good quality. > Patrick > [quoted text clipped - 9 lines] > > If you want the simplest possible, use pyrogallol dissolved in TEA. It > > produces a stained image of very good quality. I'll have to test that. It should be a fixer if that is so. In any case, the concentrate 10 g. ascorbic acid, 0.25 g phenidone in 100 ml TEA, diluted 1+50 of water, develops HP5+ in 9.5 minutes to normal contrast. If acutance does not suffers, that would be the simplest possible long life fine grain dev! Jorge > I'll have to test that. It should be a fixer if that is so. In any case, > the concentrate 10 g. ascorbic acid, 0.25 g phenidone in 100 ml TEA, > diluted 1+50 of water, develops HP5+ in 9.5 minutes to normal contrast. Hmmm, he has a scripted answer at the ready - why do I feel like the straight man in a B movie? <snicker> ... Hey, great... I will look up the issue when I get to the bookstore this week... denny "Patrick Gainer" <pgainer@rtol.net> wrote in message > > denny > Read my article in Photo Techniques Mar/Apr issue. Use triethanolamine > (TEA) as solvent in the stock solution. It is an organic base that > doesn't become alkaline until you add water. I cannot find the grain in > a 20X enlargement without a loupe. Dan Quinn wrote > > > I'll stick with the low sulfite brewing I've been doing. For > > > ascorbic acid, which I've not used for sometime, bisulfite to > > > insure acidity will do. Dan > Ascorbic acid is more acidic than sodium ... bisulfite. ph 2.3 Both 1% solutions. ph 3.2 > Ascorbic acid and sodium bisulfite will react to form sodium ascorbate, > water and sulfur dioxide. Some part of the sulfur dioxide will escape to > the atmosphere (you can tell by the smell) thus weakening the acid. You > will wind up with a higher pH than if you had used ascorbic acid alone. Sodium ascorbate will form only if sulfurous acid is formed in such quantity as to expell sulfer dioxide from solution. Using a special solution preperation technique similar to the one used for metol but a little more involved, I dissolved one gram of A. acid and four grams of bisulfite in 125ml of distilled water. I had to stir and stick my nose in the beaker to detect the very little gas produced. There was no effervescence. Sulfer dioxide, SO2 is VERY soluable. In solution it exists as sulfurous acid. I've not measured the ph of the solution but think it about 3. In a few days I may break out my pHep ph meter, recalibrate, and due some measurments. > How do you explain the fact that after all efforts have been made to > exclude oxygen from a distilled water stock solution, and the solution > is quite acidic, and the bottle is full, and the solution has not been > used even once, the solution changes color and weakens with time? "...weakens with time?" How much time, years, decades? My brown boston rounds have Polycone caps. > The fact remains that I left a thin layer of glycol-ascorbate-phenidone > stock solution exposed to air at room temperature for 16 days. The test > I did after 16 days was no different from the test I did on first > mixing. Testing your luck. You could end up with sugar ants licking their chops. They are a problem where I live. Dan > Ryuji Suzuki states that the iron/ascorbic acid reaction (that kills > ascorbic) is very active at low pH and is inactive (IIRC) at pH of 10 or > above. That has been my experience with a very short lived ascorbic > stock solution with lots of boric acid - it lasted for about one week... > See the notes in his site. Jorge R. Suzuki's site should have a better index. I've trouble finding specific items of interest. The bicarbonate/carbonate mix is one. Mr. Gainer suggests an ascorbic/bisulfite mix will not work. I'll likely find out today. That is another site I've been trying to refind: the site dealing with redox and some detail on the ascorbic/sulfite ph relationship. Dan > > I'll stick with the low sulfite brewing I've been doing. For > > ascorbic acid, which I've not used for sometime, bisulfite to > > insure acidity will do. > > Dan > > Ryuji Suzuki states that the iron/ascorbic acid reaction (that kills > > ascorbic) is very active at low pH and is inactive (IIRC) at pH of 10 or [quoted text clipped - 13 lines] > > > insure acidity will do. > > > Dan Dan, I did a quick and dirty test. I mixed a teaspoon each of ascorbic acid and sodium sulfite in some water. I don't have a pH test other than indicator solutions from a swimming pool test kit, but it said the pH was around 6.8. A solution of ascorbic acid is supposed to be about 3, but my kit doesn't go that low. I did, however, get the nose-burning odor of hydrogen sulfite. I think you should leave out the bisulfite and even sulfite from the stock solution, stick to a divided stock, and add whatever alkali and/or sulfite to the second solution. I have a feeling that something happens between phenidone and ascorbic acid any time they are together in water. Patrick My standared dev is Sol A - ascorbic+phenidone in Pglicol (4 months old, partially filled glass bottle, still going strong). For Sol B, I've used borax+sulfite. Not a good idea - sulfite slowly oxydizes to sulfate and the working solution becomes weaker. The way to mix a long lasting dev using sulfite is to mix sol B with borax only and add a spoon (mine weights about 7.5g) per 300cc of working solution of sulfite at mixing time. Jorge > Dan, > I did a quick and dirty test. I mixed a teaspoon each of ascorbic acid [quoted text clipped - 7 lines] > a feeling that something happens between phenidone and ascorbic acid > any time they are together in water. > Patrick > [quoted text clipped - 21 lines] > > a feeling that something happens between phenidone and ascorbic acid > > any time they are together in water. Do you fellows really believe that the sulfite or bisulfite actually improves something? I can't find anything wrong with the sulfite-free developer. I do use a little sulfite with PQ when I don't want the stain in order to activate the superadditivity. It takes no more than one gram for each gram of hydroquinine in the solution. If you add enough sulfite, you will get mushy grain. Undoubtly sulfite has a very pronounced effect on PA devs. If one develops without any sulfite for the same film/time/temp/concentration, using borax as accelerator (12g/liter working), negatives will be thin to the point of been unprintable. Add sulfite to 25g/liter working, and all is swell (I did not test less than 25g/liter but looks like this is close to the lower limit). Jorge > Do you fellows really believe that the sulfite or bisulfite actually > improves something? I can't find anything wrong with the sulfite-free > developer. I do use a little sulfite with PQ when I don't want the > stain in order to activate the superadditivity. It takes no more than > one gram for each gram of hydroquinine in the solution. If you add > enough sulfite, you will get mushy grain. > Undoubtly sulfite has a very pronounced effect on PA devs. > If one develops without any sulfite for the same [quoted text clipped - 4 lines] > > Jorge The problem is you do not know if it is the sulfite ion or just the extra pH that is doing the job. If you try a borax-carbonate buffer of equal amounts, about 5 grams of each per liter of working solution, you will not get weak negatives. The grain will not be coarse,either. Pat Patrick AFAIK borax is a very good buffer, and at 12g/liter there's plenty of it to keep a bit of sulfite in control. Besides, James in Theory of the Photographic Process states that emulsion speed was significantly enhanced by adding sulfite to ascorbic acid. I feel both of we are happy with yours PA in Pglicol mix. My viewpoint is that low pH is better, yours is that it doesn't matter that much. Splitting hairs, maybe? Jorge >> Undoubtly sulfite has a very pronounced effect on PA devs. >> If one develops without any sulfite for the same [quoted text clipped - 10 lines] > will not get weak negatives. The grain will not be coarse,either. > Pat > Patrick > [quoted text clipped - 10 lines] > > Jorge Not really. I would have thought you would be willing to try it without sulfite but with a higher pH. Yes, borax is a good buffer alone, but with only one pH, practically. The functions of sulfite as alkali and sulfite as a bunch of other things cannot easily be separated. I know of my own experience that increasing pH by adding sulfite is not always the best way to do it. I'm a bit under the weather now. When I can get back in the darkroom, I will prepare some examples that I can send by snail mail. Regards' Pat Gainer Sorry to hear you are not feeling well, Patrick... denny "Patrick Gainer" <pgainer@rtol.net> wrote in message > I'm a bit under the weather now. When I can get back in the darkroom, I > will prepare some examples that I can send by snail mail. >The problem is you do not know if it is the sulfite ion or just the >extra pH that is doing the job. If you try a borax-carbonate buffer of >equal amounts, about 5 grams of each per liter of working solution, you >will not get weak negatives. The grain will not be coarse,either. >Pat Unfortunately I'm no chemist and I can't understand how Borax would be a buffer for carbonate. Could you explain this ? Also, I have added as little as 2 grams of carbonate to a liter of D-23 and I can assure you that the granularity that resulted is both coarse and unacceptable. Regards, John S. Douglas, Photographer - http://www.darkroompro.com Please remove the "_" when replying via email I'm not a chemist, also, but look this way: Borax in solution dissociates and gives both H+ and OH- ions, and there is an equilibrium point among them to stabilize at about ph 9.2. When you add carbonate, there will be less OH- and more H+, avoiding the full rise of pH of carbonate alone (it's almost as if borax had become boric acid). I hope the above is right... Jorge > Unfortunately I'm no chemist and I can't understand how Borax > would be a buffer for carbonate. Could you explain this ? [quoted text clipped - 7 lines] > John S. Douglas, Photographer - http://www.darkroompro.com > Please remove the "_" when replying via email > I'm not a chemist, also, but look this way: > Borax in solution dissociates and gives both H+ and OH- ions, and there is [quoted text clipped - 4 lines] > > I hope the above is right... Maybe, but not well explained. Both borax and washing soda are the normal salts of weak acids; tetraboric and carbonic. The two have no H+ or OH- to give to a solution. When the two sodium salts are dissolved the Na+ go there way and the B4O7-- and CO3-- go there way taking some H+ with them. At any one instant in time there will be in solution; Na+, OH-, H+, CO3--, HCO3-, H2CO3, B4O7--, HB4O7-, and H2B4O7. Also, borax hydrates to the meta and ortho form. So at any one instant in time add, BO3---, HBO3--, H2BO3-, H3BO3, BO2-, and HBO2 Because the two weak acids have such an attachment for H+ and Na+ none for OH-, the solution is alkaline. The borax/washing soda solution is a buffer against a rise or fall of ph within a certain range. The CO3-- ion has likely the strongest H+ affinity and the B4O7-- ion second strongest. Those two slots are probably well filled in at the instant of solution; there by an alkaline solution. If I had more complet tables of ionization I could add to the above. I've nothing on tetraboric acid. Now everything should be clear, right? Dan > Undoubtly sulfite has a very pronounced effect on PA devs. > If one develops without any sulfite for the same > film/time/temp/concentration, using borax as accelerator (12g/liter > working), negatives will be thin to the point of been unprintable. > Add sulfite to 25g/liter working, and all is swell... That reaction to the sulfite addition is due to the increase in ph. If I recall correctly 1% solutions of borax and sulfite measure 9, and 10.6. Sulfite will up the ph way above borax. Crawley via P. Dignan states, ... sulfite removes surface flare and image spread. He is speaking of FX-13. R. Suzuki adds sulfite to FX-1, IIRC, to improve the gradiation. I'm about to brew up some FX-1 and should investigate the matter. Dan No, sulfite does not rises pH of a borax solution, actually it lowers a little bit. I've mixed a borax 12g/l solution, measured pH and then added sulfite at 25g/l. pH went down by 0.2 pH (at lest using my meter). It has to do with exposing dev centers or alike. Jorge >> Undoubtly sulfite has a very pronounced effect on PA devs. >> If one develops without any sulfite for the same [quoted text clipped - 10 lines] > I'm about to brew up some FX-1 and should investigate the matter. > Dan > No, sulfite does not rises pH of a borax solution, actually it lowers > a little bit. I've mixed a borax 12g/l solution, measured pH and then > added sulfite at 25g/l. pH went down by 0.2 pH (at lest using my meter). > > It has to do with exposing dev centers or alike. I've not combined borax and sulfite and then measured the ph. I will duplicate the above conditions and post the results. Dan > >> Undoubtly sulfite has a very pronounced effect on PA devs. > >> If one develops without any sulfite for the same > >> film/time/temp/concentration, using borax as accelerator (12g/liter > >> working), negatives will be thin to the point of been unprintable. > >> Add sulfite to 25g/liter working, and all is swell... Dan wrote: > > That reaction to the sulfite addition is due to the increase in ph. > > If I recall correctly 1% solutions of borax and sulfite measure [quoted text clipped - 4 lines] > > I'm about to brew up some FX-1 and should investigate the matter. > > Dan >Do you fellows really believe that the sulfite or bisulfite actually >improves something? I do as did Grant Haist and C.E.K.Mees. Film speed and edge sharpness are both improved when sulfite is used in moderation. Regards, John S. Douglas, Photographer - http://www.darkroompro.com Please remove the "_" when replying via email > >Do you fellows really believe that the sulfite or bisulfite actually > >improves something? [quoted text clipped - 5 lines] > > John S. Douglas, Photographer - http://www.darkroompro.com Please remove the "_" when replying via email John, But you did not start with a completely sulfie-free stock solution. Adding carbonate to D-23 is not the same as adding sulfite to a phenidone-ascorbic acid-carbonate developer, or a metol-ascorbic acid-carbonate developer, or a phenidone-hydroquinone-carbonate developer. At least, not until the sulfite concentration becomes fairly large. That is not my approach. I say start with no sulfite and gradually increase the concentration until something happens. You may find that what other people (even I) may say is not generally true, just as linearized potential aerodynamic flow theory fails at high Mach numbers and rounded leading edges. I tend to think we are on opposite sides of a photographic "sound barrier" and until we pass through it we will not see the whole story. Hi everyone, best wishes Patrick for a speedy recovery. It must be exhausting trying to explain that in some developers that Sulphite actually hinders rather than helps some developers - over and over again... ;-) Especially when it's true. I just wanted to post a follow-up to this developer, it is indeed amazing and I printed up a 6x6cm neg (Apx100) to 10x10 in it. No grain through my magnifier (Micromega Critical Focusser) and amazingly beautiful tones - on the paper that is. I have a new favorite developer. Thanks again Pat for introducing me to a (relatively) non toxic staining developer. Works wonderful. One caveat however, I will probably alter the dilution to at least 1:75 (most likely 1:100) because the time is too short with my normal metaborate-like alkaline component (around 5mins). Cheers > Hi everyone, best wishes Patrick for a speedy recovery. It must be > exhausting trying to explain that in some developers that Sulphite [quoted text clipped - 9 lines] > too short with my normal metaborate-like alkaline component (around > 5mins). Cheers Nicholas, I'm back in good health. It was some kind of intestinal bug. I used to call it "24 hour crud" but everything is slower now, so it's more like 48 hours. I believe I promised to send some negs and prints to demonstrate some of the things I have learned lately. First one to supply a snail mail address gets it. That person can pass the package on down the list if there are more than one. Pat Dr. Dennis O'Connor 570 N. Hemlock Rd. PO Box 439 Hemlock, MI 48626 > > Hi everyone, best wishes Patrick for a speedy recovery. It must be > > exhausting trying to explain that in some developers that Sulphite [quoted text clipped - 21 lines] > > Pat > Dr. Dennis O'Connor > 570 N. Hemlock Rd. [quoted text clipped - 26 lines] > > > > Pat You're on, Denny me boy. Tomorrow I will take to the post office a package containing 3 prints, 3 negative strips for the prints, and 3 negative strips of step density wedge developed together with corresponding picture negatives. Film is 400TX. The developer is the PC-Glycol concebtrate diluted 1+50 with a) 5 g pHPlus and 5 g borax per liter; b) the same with 20 g of sulfite added per liter; and c) 100 grams of sulfite + 2 grams of Kodalk (the real stuff) per liter. You may be surprised at what you see. Pat Jorge Oliveira Al Carlos carvalho 928/8 80430-180 Curitiba PR Brazil Jorge > I'm back in good health. It was some kind of intestinal bug. I used to > call it "24 hour crud" but everything is slower now, so it's more like [quoted text clipped - 6 lines] > > Pat |
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