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Photo Forum / Film Photography / Darkroom / October 2006SOAKING NEGS
I don't have any photo flow. What's the next best way to soak negs? DNT spake thus: > I don't have any photo flow. What's the next best way to soak negs? Dilute soap (like dish detergent). Just a drop in a lot of water (gallon or more).  SignatureIn order to embark on a new course, the only one that will solve the problem: negotiations and peace with the Palestinians, the Lebanese, the Syrians. And: with Hamas and Hizbullah. Because it's only with enemies that one makes peace. - Uri Avnery, Israeli writer and peace activist with Gush Shalom. (http://counterpunch.org/avnery08032006.html) > I don't have any photo flow. What's the next best way to soak negs? Photo Flo is normally used as the final processing step in order to reduce water drying spots. If this is what you want, two other options are to use a distilled water rinse without a wetting agent or to use a drop or two of liquid dishwashing detergent (the sort used for manual washing, not the type that's used in dishwashers) in the final rinse water. I've heard from a retired Kodak chemist that dishwashing detergents might have negative long-term effects on film, but I've also seen reports from people who've used dishwashing detergents for years and don't seem to have problems. Film wetting agents are cheap enough that the only reason I can think of to use dishwashing detergent instead is if you're out of true wetting agent and can't get it for some reason or in time to do the processing. SignatureRod Smith, rodsmith@rodsbooks.com http://www.rodsbooks.com Author of books on Linux, FreeBSD, and networking On Mon, 28 Aug 2006 06:07:44 -0000, rodsmith@nessus.rodsbooks.com (Rod Smith) wrote: >use >a distilled water rinse without a wetting agent August 28, 2006, from Lloyd Erlick, That's what I've done for years. It's absolute protection from water spots. My 'refinement' of the method is that I hang my rolls of film when finished, and squirt them from top to bottom on both sides from a plastic bottle full of distilled water. Actually, I do have a dishwashing-detergent connection: the closure of the common type of dish soap container from the supermarket makes a perfect squirter for dribbling the distilled water down my films. It's easy to clean of the soap when retrieved from the garbage, too! Right now I have a one liter Coca Cola bottle full of distilled water, with a dish soap dispenser cap on it. Eventually the Coke bottle will split and I'll have to replace it at the huge cost of rinsing one out. It might even be an improvement over this technique to soak the film in several changes of distilled water, allowing enough time for anything absorbed into the emulsion to soak out. Say three changes of distilled water, for three to five minutes each or thereabouts. This way would cost a bit more because it would use more distilled water. And it would take longer to do. Neither way seems a huge cost... When I moved a few years ago, I left the wetting agent behind. It had been unopened for twenty years or more. (I actually hate the stuff because of its evil odour. Yes, I'm a bit weird when it comes to smells in my darkroom...). regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- > On Mon, 28 Aug 2006 06:07:44 -0000, > rodsmith@nessus.rodsbooks.com (Rod Smith) [quoted text clipped - 52 lines] > email: portrait@heylloyd.com > ________________________________ Distilled water can elminate rings caused by deposits of minerals from the water but will not elmimate drying marks caused by droplets of water. These marks are caused by uneven shrinkage of the gelatin as it drys. Squeegeening the film will eliminate both. The use of a wetting agent helps because it eliminates the dange of scratching the film when squeegeeing. A good film squeegee is soft sponge, harder rubber squeegees tend to cause more scratching. a very small amount of dishwashing detergent along with some rubbing alcohol makes a good final rinse. Photo-Flo is better because it is intended for film but the detergent is mostly made up of a similar wetting agent. The alcohol in combination with either makes a sort of super wetting agent. For Photo-Flo use about 35ml of 70% Isopropyl rubbing alcohol and about 2.5ml of Photo-Flo per liter of water. If the tap water in your area is very dirty or has a lot of minerals in it making the rinse up with distilled water helps eliminate deposits of minerals and dirt. If no distilled water is available use tap water that has been boiled for about five minutes and allowed to stand while cooling. The boiling removes some hardness (deposited on the vessle) and will coagulate organic matter. This is also a good procedure for water to be used to make up darkroom chemicals because it drives off dissolved gasses. Signature--- Richard Knoppow Los Angeles, CA, USA dickburk@ix.netcom.com >Distilled water can elminate rings caused by deposits of >minerals from the water but will not elmimate drying marks >caused by droplets of water. These marks are caused by >uneven shrinkage of the gelatin as it drys. August 29, 2006, from Lloyd Erlick, I've hung my rolls of film and squirted them with distilled water for years. Many, many rolls have been sprayed by 'overspray' from the other rolls. Often they have been dry or close to dry when this happened. I have never had a visible drying mark from this cause. When I first started this practice, I thought overspray on dry or partially dry rolls might be a problem, but I could never see any effect. The same has been true of prints hung to dry. The types of film one uses obviously will determine the effect of droplets drying on the film. I mainly use Kodak film these days, almost always T-Max 400 (TMY) in 120 format. I've also found no problem from Tri-X, and from Ilford HP5 and D3200. Also, the Agfa films I tried (APX types) showed no detrimental effects. My opinion, based on handling the actual films, is that current production films do not suffer from these effects. I can't speak for the films that are sometimes promoted as old tech. I've never used Foma or Efke products, for example. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- >Squeegeening the >film will eliminate both. The use of a wetting agent helps >because it eliminates the dange of scratching the film when >squeegeeing. A good film squeegee is soft sponge, harder >rubber squeegees tend to cause more scratching. August 29, 2006, from Lloyd Erlick, I have adopted a policy of permitting nothing to touch the image areas of my photosensitive materials while they are wet. Only processing solutions and water are permitted. Excluded are hands, fingers, tongs, squeegees, flat work surfaces, drying screens and anything else. This practice gives me the ability to make absolute statements about my work; statements that are impossible otherwise. For example, my prints and films are absolutely free of contamination from a squeegee. They are absolutely free of scratches and creases caused by a squeegee. My non-existent drying screens transfer absolutely nothing to my prints -- absolutely no chemicals, and absolutely no bits of dirt and crud to embed in the print coating come from drying screens in my drkroom. It might appear my method somehow adds labor and raises the level of difficulty of the whole activity. However, this is not the case. Overall, my methods have abbreviated the whole process of making a rigourously processed product, whether film or print. I use one tray, which is much easier than a line of multiple trays. The absence of drying screens is a wonderful, freeing, tension-reducing space of unoccupied volume where the stack of filthy screens would otherwise squat in my place. The hours of painstaking examination of the acreage of screen surfaces for bits of dirt and fibers that could transfer to my prints is mercifully absent. The ease of hanging a print to dry is a marvellous feeling compared to the heart in mouth feeling of flipping a print all over the place to squeegee it. The gambling with a film squeegee is a thing of the past (did I clean it enough? is it really wet or does it have a dry spot? is there any grit in there?). I forgot to mention: absolutely none of my films have been damaged by a squeegee for over twenty years. But I do not advocate throwing out the squeegee. It's an important sink cleaning tool. Also, if you cut out a handful-size patch of mesh from a drying screen and ball it up, it will be perfect for scrubbing out a sink. This would also be a good place to use that dish washing soap, instead of on rolls of film. Sometimes a pair of tongs is useful if something falls down the drain, although most tongs I've seen are second rate even for this duty, compared to fingers. Depends what fell down the drain ... Most of the time my comments are based on darkroom work with 'ordinary' or 'normal' or 'usual' or 'unspecialized' materials. Many people use specialized materials (old-tech films, self-coated papers, film stored for many years, etc) or processes (PMK, alt process, etc) and I can't say anything about them. But for current, ordinary Kodak films (and Ilford) of the TMY or HP5 ilk, *careful* hand processing eliminates the need for many different tools and techniques. I'd include a rinse in water containing alcohol in the specialized group. It's fine for a special purpose, such as getting the film dry in a hurry because there is some pressing need. But for ordinary practice, the smell of alcohol is not necessary in the darkroom. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- >I have adopted a policy of permitting nothing >to touch the image areas of my photosensitive >materials while they are wet. At the risk of repeating myself, I still think that the way you put it in that technical article on your web site: >Drying Screens Get Out of Town If You Know What's Good for You, and >Take Squeegee With You, Too! is one of the funniest things I've seen in a long time! >>I have adopted a policy of permitting nothing >>to touch the image areas of my photosensitive [quoted text clipped - 7 lines] > >is one of the funniest things I've seen in a long time! August 30, 2006, from Lloyd Erlick, Thanks! (Repeat yorself all you like ...) regards, --le >>>I have adopted a policy of permitting nothing >>>to touch the image areas of my photosensitive [quoted text clipped - 14 lines] > regards, > --le OK then. -- In lew of distilled water is filtered water OK? If so which of the following would be most useful? The charcoal in a plastic container that works fast. _ or the upbeat ceramic / charcoal device that's a lot slower _ or the more complex multi filtering layer hi tech wizzmo that I wonder is more geared to baffling consumers than giving you tasty water. SignatureOtzi >>>>I have adopted a policy of permitting nothing >>>>to touch the image areas of my photosensitive [quoted text clipped - 22 lines] > filtering layer hi tech wizzmo that I wonder is more geared to baffling > consumers than giving you tasty water. >hi tech wizzmo that I wonder is more geared to baffling consumers than >giving you tasty water. August 31, 2006, from Lloyd Erlick, Well, you've hit it on the head, I think. Frankly, I don't trust 'filtered' water. Too many questions about the filter, such as, when is it no longer working properly and letting stuff through?? I like the expression 'steam distilled'. I have a counter top water distilling machine in my kitchen. It boils and condenses the water and I've found it close enough to pure that I've never seen a water spot from it on my negs. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- >>hi tech wizzmo that I wonder is more geared to baffling consumers than >>giving you tasty water. [quoted text clipped - 23 lines] > email: portrait@heylloyd.com > ________________________________ Can you post a link or two re this device. I am not aware of anything similar in AU SignatureOtzi ... a counter top water distilling machine >> in my kitchen. It boils and condenses the >> water and I've found it close enough to pure [quoted text clipped - 3 lines] >> regards, >> --le ... >Can you post a link or two re this device. I am not aware of anything >similar in AU September 4, 2006, from Lloyd Erlick, I don't have links handy, but I remember using Google to search for home kitchen water distillers. There are many sellers, and several different machines. The most common machine is called by one seller the "Love Distiller". Hmp. But it's the one I have, and it's the cheapest. (Mine has a label that says "Ecowater Systems".) It's basically a cylinder that tapers slightly toward the top. The bottom has a stainless steel tank (inside, the outside is painted variously, white is cheapest) and a heater. The top (round) lifts off, and contains a fan and cooling tubes and fins. The outside of the top has open slots to admit air around the tubes. The product water comes out a short spout near the top. I've used one for over ten years (I'm now on my second machine; the first provided 6500 liters of product water). I calculate that the distilled water cost is around twenty cents a liter, including original cost of machine, electricity and municipal water. I prefer it to buying jugs of water at the store and lugging them home, then deploying the waste containers somehow. (The cost of electricity has increased quite dramatically over the last decade. The machine is rated at 470 watts, and seems to take a little under eight hours to distill a fill-up of four liters. I've measured the output, and it is 3.8 liters.) I think of it as a kilowatt-hour per liter of product water. None of the added-cost extras they try to sell are necessary. The special liquid to clean the interior tank is not needed (use vinegar, or nothing. I just swill and dump before filling. A plastic scrubber would be quite a luxury. The buildup inside tends to flake off as it builds up, so swilling gets rid of it. Avoid anything that might scratch the interior.) The flavor-enhancing filter is not needed for darkroom water, and if you want to polish the product water for flavor, use a common Brita filter. (I find I can taste the flavour of iron or steel if I drink the distilled water. No doubt this is from the machine's tank. After passing through a Brita, it's fine. Many people claim distilled water does not taste good; they describe it as flat. I find it tastes very nice after going through the Brita; a rest in the refrigerator is good, too. Pouring the water back and forth between two containers aerates it (I think dissolving oxygen in it improves flavour). Of course, the action of the distiller as it distills the water (i.e., as it boils and condenses it, and drips it drop by drop through the air into its container ...) aerates it quite thoroughly. Anyway, I like to use the water to drink plain, or for drinks of all sorts (sure wish I could drink coffee, I used to love distilled water for that). It's nice as seltzer, too. Some people claim distilled water is excessively able to dissolve substances, and so will rob the body of vitamins and minerals that are water soluble. I think this is a maybe-so, but I do not believe the reasonable alternative is to drink water out of Lake Ontario. Maybe eating food that contains vitamins and minerals ... along with the distilled water ... anyway, my teeth are in good shape and none of my internal organs has dissolved. I used to be five and a half feet tall, now I'm only three ten, so maybe I've made a mistake ... regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- > ... a counter top water distilling machine >>> in my kitchen. It boils and condenses the [quoted text clipped - 7 lines] >>Can you post a link or two re this device. I am not aware of anything >>similar in AU My parents have a 4640 from Durastill: http://www.durastill.com/index.html. Danged thing still works, too, and they bought it in 1980. Looks just the same as the one on the above page. Lloyd Erlick wrote (in part): > Frankly, I don't trust 'filtered' water. Too > many questions about the filter, such as, > when is it no longer working properly and > letting stuff through?? Filtering water with a 5 micron filter is what I do for wash water. An activated charcoal filter may remove some dissolved gasses. No ordinary filter will remove dissolved salts, such as calcium carbonate. Perhaps an ion-exchange gizmo will replace some of the "harder" salts with softer ones (sodium salts), but if you are drying films with water droplets on them, this is not much better. I suppose a reverse osmosis filter would be suitable, but distilling the water is surely the best. I compromise and use filtered condensate from my dehumidifier for sensitive solutions, especially PhotoFlo for negatives. Signature.~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey http://counter.li.org ^^-^^ 16:55:01 up 1 day, 19:44, 3 users, load average: 4.28, 4.27, 4.21 > I compromise and use filtered condensate from my dehumidifier for sensitive > solutions, especially PhotoFlo for negatives. & you don't worry that the condensate may contain algae or worse some sort fungus? SignatureReality-Is finding that perfect picture and never looking back. www.gregblankphoto.com >> I compromise and use filtered condensate from my dehumidifier for sensitive >> solutions, especially PhotoFlo for negatives. > > & you don't worry that the condensate may contain algae or worse some > sort fungus? No, I do not worry. This does not mean you are wrong and that I know there are no algae or fungus. It is just that I filter the condensate and that should get rid of the big lumps. Also, in 30 years, I have never had a problem with that. Signature.~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey http://counter.li.org ^^-^^ 08:10:01 up 2 days, 10:59, 3 users, load average: 4.28, 4.17, 4.11 >>> I compromise and use filtered condensate from my dehumidifier for sensitive >>> solutions, especially PhotoFlo for negatives. [quoted text clipped - 6 lines] >should get rid of the big lumps. Also, in 30 years, I have never had a >problem with that. September 5, 2006, from Lloyd Erlick, But Greg's point may be that micro-organisms or spores are introduced into your photosensitive materials, to lie in wait for the great day of reproduction and feasting upon gelatin, leaving your tiny particles of silver unsupported ... However, conditions suitable for this type of degradation of stored photo materials are warm and moist. If negs are archived in too much warmth and moisture (humidity, that is) it doesn't much matter if the wash water had a few bacteria or spores. That might accelerate the process, but poor archive conditions will activate bugs passing by, irrespective of our wash water. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- > However, conditions suitable for this type of > degradation of stored photo materials are > warm and moist. it doesn't much matter ... > a few bacteria or spores It doesn't much matter ... the acetate base will disintegrate under such conditions. I have had 'lens style' fungus - spidery stuff - on negatives that spent twenty years in a damp corner of the basement. The growth was on the back side of the film. SignatureNicholas O. Lindan, Cleveland, Ohio Darkroom Automation http://www.nolindan.com/da/index.htm n o lindan at ix dot netcom dot com > have had 'lens style' fungus - spidery >stuff - on negatives that spent twenty >years in a damp corner of the basement. >The growth was on the back side of the film. September 5, 2006, from Lloyd Erlick, mmm, it likes vinegar with its molecules ... > "Nicholas O. Lindan" <see@sig.com> wrote: > > [Bad storage = cellulose acetate -> acetic acid] > > have had 'lens style' fungus - spidery > > stuff - on negatives > mmm, it likes vinegar with its molecules ... Vinegar is always a good accompaniment to jellied meats. SignatureNicholas O. Lindan, Cleveland, Ohio Darkroom Automation http://www.nolindan.com/da/index.htm n o lindan at ix dot netcom dot com On Mon, 04 Sep 2006 18:13:10 -0400, "Greg \"_\"" <grey_egg@greg_photo.com> wrote: >> I compromise and use filtered condensate from my dehumidifier for sensitive >> solutions, especially PhotoFlo for negatives. > >& you don't worry that the condensate may contain algae or worse some >sort fungus? September 5, 2006, from Lloyd Erlick, That's definitely a concern. However, the water contains relatively little nutrient matter, even for micro-organisms. (Filtering out insect parts is not a major activity. Actually, once the container is covered, no bugs get in. They don't provide much food for algae.) I've had five gallon containers of dehumidifier water last for years with no growth or smell. I was always too much the city boy to actually drink any, but a basic precaution like boiling it would eliminate the problem. I find the worst water for growing nasty stuff is old tap water. Stored tap water soon develops an evil smell. Concerns about algae and the like can be addressed by boiling, using a few drops of chlorine bleach (don't use right away for darkroom solutions ...) or a bit of swimming pool / humidifier disinfectant. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- >Filtering water with a 5 micron filter is what I do for wash water. ... >I compromise and use filtered condensate from my dehumidifier for sensitive >solutions, especially PhotoFlo for negatives. September 5, 2006, from Lloyd Erlick, I'd say filtering wash water is going pretty far for your negatives! I have the luxury of municipal water treatment; we all know how pure and clean city water is, eh?? Shrewsbury Artesian probably tastes pretty good ... Dehumidifier water makes great solutions. I suppose it must have lots of dissolved gases, and I always had to filter out parts of insects, but it never left any water spots on my negs, and that's all I cared about. It must be cheaper than a distiller, too. Using dehumidifier water is making use of Mother Nature's Great Big Water Distiller ... regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- >> Filtering water with a 5 micron filter is what I do for wash water. > ... [quoted text clipped - 4 lines] > > I'd say filtering wash water is going pretty far for your negatives! Well, I also mix most solutions with that, too. I use condensate mostely for mixing up PhotoFlo and the stop bath (SB-5) for 35 mm negatives. > I have the luxury of municipal water treatment; we all know how pure and > clean city water is, eh?? Shrewsbury Artesian probably tastes pretty good > ... "Shrewsbury Artesian" actually tastes pretty bad. Not anymore, but when I first moved in here I could not drink it at all and had to go bottled water. But after some months it got so I could drink it. Using the stuff right out of the tap left problems on negatives, so I installed a water filter for my darkroom. I think it came with a 20 micron filter and that seemed good enough, but it clogged up with disgusting brown stuff after a few months. I later started using 5 micron filters. They clog too. I think Shrewsbury Artesian may have killed all the bugs, but is leaves the solid crud in the water. I like to think of it as rust and other iron deposits, but it look more like $h|t. > Dehumidifier water makes great solutions. I suppose it must have lots of > dissolved gases, and I always had to filter out parts of insects, but it > never left any water spots on my negs, and that's all I cared about. It > must be cheaper than a distiller, too. Using dehumidifier water is making > use of Mother Nature's Great Big Water Distiller ... I would suspect it is about the same price as a distiller because of the electricity used to condense the water vapor is 540 calories per gram of water, assuming 100% efficiency and I am sure the efficiency is less than that. It also takes 540 calories/gram to boil the water in the still. Signature.~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey http://counter.li.org ^^-^^ 07:00:01 up 4 days, 9:49, 3 users, load average: 4.37, 4.22, 4.08 To carry the thing further: 41 KJ/mole Heat of vaporization 18 gm/mole molar weight of water 2.3 KJ/gm 100C water -> steam for 1gm|1cc + 335 J/gm 20C water -> 100C (80 cal) =========== 2.6 KJ/gm To vaporize 20C water 2.6 kW-Sec/gm .72 KW-Hr/l x $0.13/KW-Hr In Cleveland, OH =========== $0.095/l $0.36/gal An electric submersion heater with a well insulated vessel can approach 100% efficiency. Give a kitchen still 80% at a guess. Electricity cost should be about 45 cents/gallon. Steam distilled water is 69 cents/gallon at the local grocery. SignatureNicholas O. Lindan, Cleveland, Ohio Darkroom Automation http://www.nolindan.com/da/index.htm n o lindan at ix dot netcom dot com > To carry the thing further: > [quoted text clipped - 19 lines] > > Steam distilled water is 69 cents/gallon at the local grocery. What if you rigged a solar distillation apparatus? Far less $ I guess. SignatureReality-Is finding that perfect picture and never looking back. www.gregblankphoto.com Greg "_" spake thus: >>To carry the thing further: >> [quoted text clipped - 21 lines] > > What if you rigged a solar distillation apparatus? Far less $ I guess. Now you're into figuring out how long the payback period is. (Same problem with people installing PV panels on their houses.) They're not cheap. SignatureNapoleon won the battle of Waterloo. The German Wehrmacht won World War II. The United States won in Vietnam, and the Soviets in Afghanistan. The Zealots won against the Romans, and Ehud Olmert won the Second Lebanon War. - Uri Avnery, Israeli peace activist (http://counterpunch.org/avnery09022006.html) >To carry the thing further: > [quoted text clipped - 19 lines] > >Steam distilled water is 69 cents/gallon at the local grocery. September 8, 2006, from Lloyd Erlick, The best deal on distilled water I have seen locally is C$0.99 for a four liter container, at the supermarket. Call it twenty five cents a liter. These days (according to the readout last night on the news) one US$ = C$1.11. I've been looking at water distilled in the machine as twenty cents a liter. Slightly better price, and much better convenience. It still has to be carried around, but not far, and not all at once. Garbage is getting to be an issue around here, and I'd like to avoid having to deal with an unending stream of plastic containers. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- Has anyone answered WHY soaking negs is important? Take just one case: Efke 25 sheet film - it is suggested that it be soaked before any kind of processing (drum, tank or tray). WHY? Is the antihalation layer which is washed off in soaking a developer contaminent? tia > Has anyone answered WHY soaking negs is > important? Take just one case: Efke It swells and saturates the emulsion with water so when the developer is added it goes into the emulsion evenly. Some films streak/puddle/spot if not pre-wet: a bit like paper if the developer puddles over it before it is covered with the fluid. Paper is developed to completion and so the puddling has little effect in the end. Film isn't developed to completion and the outlines of the developer puddles/streaks from the tank being filled don't always disappear. It seems thin emulsion films are more sensitive to the effect, I have only had bad reactions of this sort with TechPan. SignatureNicholas O. Lindan, Cleveland, Ohio Darkroom Automation http://www.nolindan.com/da/index.htm n o lindan at ix dot netcom dot com Reverse osmosis (RO) should be a lot cheaper than distillation for purifying water. It will remove virtually all dissolved salts. One little note: RO units need to have a filter to remove chlorine prior to the RO filter. Otherwise the chlorine will attack the RO filter so the filter will require frequent changing. Also, it is best not to use most RO units on hard water. Run the water through a softener first. (RO filters tolerate monovalent ions (sodium) much better than divalent ions (calcium).) Costco sells an RO unit for about $130. > To carry the thing further: > [quoted text clipped - 25 lines] > http://www.nolindan.com/da/index.htm > n o lindan at ix dot netcom dot com >Using dehumidifier water is making >> use of Mother Nature's Great Big Water Distiller ... [quoted text clipped - 3 lines] >water, assuming 100% efficiency and I am sure the efficiency is less than >that. It also takes 540 calories/gram to boil the water in the still. September 8, 2006, from Lloyd Erlick, At least the dehumidifier only has to supply the energy to condense. The distiller has to boil then condense. But the condenser side of it is not electric, it uses room temperature air ... I'm not wrestling with this now. I have to go drink some Lake Ontario water for breakfast. regards, --le ________________________________ Lloyd Erlick Portraits, Toronto. website: www.heylloyd.com telephone: 416-686-0326 email: portrait@heylloyd.com ________________________________ -- |
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