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  1. #1

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    Advice with collodion glass plates

    Today was my first time, I count a chemical kit and mixed everything according to the instructions.

    frist plate... was just a ghost
    second plate an image but the upper corner stayed milky white. kind of like the power white when you remove the plate form the silver bath
    third plate . not much better light image very hard to see and some of the same white at the upper top corner.
    fourth .. i dropped the plate into the silver bath with the light on. A person I talked to said it would not matter because the plates react so slow that you come in an out of the dark room without and issue. This plate had nothing it appeared as if most of the collodion came off.
    five.. the collodion pealed.. this was the better of the images but the collodion tore their the middle of the image that it was ruined.
    6th I shot middle aperture with for ten seconds. Again the image is very light.

    Can someone give me some tips on what errors cause what issues. The collodion peal I am guessing is due to not cleaning the plates well enough. my kit did not come with plate cleaner so i tried to use dish soap and hot water. the first couple plates i cleaned and rinses well using hot hot water. the latter ones i was a bit sloppy so I am sure thats why they pealed.

    One this i do not know because i am used to seeing the images on the computer now are they really this light in person and my eyes are used to seeing the digital version. I want to try some black tin plates to see if I get a better result.

    Positive side it works but I do not really have an idea of how to figure out my exposure and when to pull from the developer. Also why i am thinking about it does it matter if i pour the developer or drop it in the tray like paper? would any of that handling cause the collodion to lift?

    I am actually pretty happy with this so far considering I really did not spend a ton of time today. What i saw is close to usable so with a bit of work I should be able to get decent results. I am shooting with a brownie 2 3/4 by 4 1/4 glass plates. I just found a half plate and its in the mail to me now will have it monday i hope. I know this is kind of all over here forgive me I have no idea what I need to do I am just playing with it. the videos i watched show the process but have no information about errors and what result indicates what mistakes.

    Help ???????????????

  2. #2

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    1. I have had good luck basing my exposure in ISO 1. I assume you are exposing the plates outside in sunlight or bright shade. Remember the plates require UV light to expose.

    2. I get best results pouring the developer on the plate in the same manner as the collodion. You don't need much developer--half a shot glass. I time the developer--15 seconds I think (I'd have to check my notes).

    3. Have you viewed your plates against a black background? Just put them on a black cloth and see how they look. Glass plates look thin compared to negatives.

  3. #3
    smieglitz's Avatar
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    Quote Originally Posted by davidseminatorephoto View Post
    fourth .. i dropped the plate into the silver bath with the light on. A person I talked to said it would not matter because the plates react so slow that you come in an out of the dark room without and issue. This plate had nothing it appeared as if most of the collodion came off.
    five.. the collodion pealed.. this was the better of the images but the collodion tore their the middle of the image that it was ruined.
    6th I shot middle aperture with for ten seconds. Again the image is very light.

    Can someone give me some tips on what errors cause what issues. The collodion peal I am guessing is due to not cleaning the plates well enough. my kit did not come with plate cleaner so i tried to use dish soap and hot water. the first couple plates i cleaned and rinses well using hot hot water. the latter ones i was a bit sloppy so I am sure thats why they pealed.
    You are probably grossly overexposing the plates. Here is a test strip sequence I shot recently using a passport camera. The exposures are all at the same aperture (f/11 IIRC) for 2, 4, 8, & 16 seconds starting in the bottom left quadrant and going clockwise.



    I'd say the darkest one is still slightly overexposed, but you get the idea of what overexposure looks like with the others.

    Give your plate a final rinse in distilled water after using a detergent or modern glass cleaning chemical. You do need to vigorously clean the plate using whiting or rottenstone. Those are essentially calcium carbonate or chalk, soft abrasives that won't scratch glass. Soft scrub cleansers are the same thing but with other stuff like perfumes in them so they should not be used for wetplate. Go to a paint or stained glass store and buy some whiting. It is super inexpensive and should solve the problem. Clean the plate with whiting and be sure to get it all off again as it will harm your silver bath pH if any is left on the glass, especially caught in the rough edge. And, get some egg white (albumen) and dip a cotton swab in it. Run the cotton around the edge of the plate so that it comes in about 1/8" on the surface you pour the collodion on. That should really solve the peeling problem. FWIW, salted collodion made with cadmium salts are more prone to peeling and I believe the kits use Old Workhorse which is a cadmium-based formula.

    Positive side it works but I do not really have an idea of how to figure out my exposure and when to pull from the developer. Also why i am thinking about it does it matter if i pour the developer or drop it in the tray like paper? would any of that handling cause the collodion to lift?
    Yeah. Rough handling with the fluid wave of developer can cause problems. The collodion might tear around the edges and then peel or there may be a dark spot where the developer first hits the plate if you pour the developer. Any unevenness in swiftly getting the plate evenly covered with a thin layer of developer will cause some sort of development artifact. If you must use a tray, collect all the developer in one end, place the plate in the tray above the reservoir of developer, and then tilt the tray so the fluid goes over the plate as a wave. You'll figure out which method works best for you in a short time. The key is to get a thin layer of developer, the minimal amount you can coat the plate with, on the plate as evenly as you can and give it gentle agitation while keeping the fluid from running off the plate. Too little or too much fluid is not good.

    And, absolutely do this: DEVELOP YOUR PLATE FOR A SPECIFIC AMOUNT OF TIME AND DON'T TRY TO PUSH (OR PULL) THE DEVELOPMENT BECAUSE YOU WILL FOG THE PLATE CHEMICALLY. ADJUST YOUR EXPOSURE TO GET GOOD RESULTS AT THAT CONSISTENT DEVELOPMENT TIME. For positives, most people use a time between 15 -30 seconds, but only one consistent time in that range. Pick 20 seconds and stick to it while adjusting developer strength and exposure to optimize your results at that specific time. Don't vary from that development time.

    One other thing that you mentioned might be a problem. I've never had luck getting regular glass to fit in a Brownie. It's too thick and prevents closing the camera properly, at least the ones I have. Aluminum works fine however. But, if the back isn't closing properly, you might have a light leak as a result that could fog your plate. Might not be a concern with your equipment.

    As far as the roomlights and the silver bath, I pour and sensitize under red safelight conditions and never have a problem even with the plate a couple feet from the bare red lamp. You can see the proximity of the silver tank and the cheap, bare, 13w red fluorescent lamp in the following picture:



    I would not sensitize under ambient tungsten or daylight fluorescent lighting. Just eliminate that variable. If you must, pour the plate under room lighting , once the collodion sets for about 30-45 seconds get it in the silver tray/tank, and then cover that while the plate sensitizes. Transfer the sensitized plate to the camera either under safelight or in total darkness to eliminate the possibility of light fog from the procedure.

    Having said that, 'togs in the mid-1800s didn't have electricity for safelights and so they used candles at some distance or behind ruby glass as safelight illumination. But then there's that thing about open flames and ether... no wonder the unlucky ones had explosions occur.

    Last edited by smieglitz; 05-16-2012 at 12:06 AM. Click to view previous post history.

  4. #4

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    Hi, Thank you for the replies. ISO 1 will get me to a decent start time.

    smieglitz.. I believe you are right. I was shoot on both wide open and medium aperture from 3 to 15 seconds. If i see your test strip and compare my images appear to be grassy over exposed. I don't think that was an understatement at all I was going the wrong way thinking that I needed longer time. I believe the majority of clips I have seen are people shooting thru window light at increased exposures.
    One question i have is are the abrasives or scrubbing done to clean or are you creating a surface for the collodion to grab on. Now that I am thinking about it glass is pretty smooth it might take some ridges for it to be able to cling on to. As for the developer and my pouring it sounds like that is what I am doing wrong. I am a bit to rough with the developer I need to be very delicate. I was under the impression the film layer was stronger than it is. From what you wrong my impression is that its very weak and tears easy. I am able to pour on the the plate without a problem I just want not sure because some of the the area of the plate looked fogged up. Now that I am thinking about it maybe that to is over exposure because the fogged area was sky or the brightest area of the plate.
    I am curious if there is a better book available I have john coffers book and videos. now that I have tried this I am going to reread and watch the videos. It will make more sense now.
    Back to my process. the brownie I have the glass fits in easily. there are two rails where the film would run. I had the class cut exactly to fit in there 2 3/4 inches by 4 1/4. the plate drops right onto the back where the film would slide. the back slides over the only issue i have is the little latches are a pain to undo with gloves. I found a thorton pickard half plate camera that is compete its on its way to me via fed ex. I should have it by monday. I could not wait though and wanted to attempt to do a few plates. My original plan was to learn on the box camera and see if i could get a decent result that i liked enough to want to pursue this further.
    for now i pour the plate with collodion in full light. I have a small dish that i have the silver bath in I placed that in a photo paper box. the light safe one from my dark room. It is kind of simple actually. the plate if fully submerged in the silver. except for the one time I am doing the sensitizing under red light. mine is father away than yours. I made need to move it because its hard to see the developing. after i expose i go back to the dark room lights off pour developer. wait then poor water then fixer. I think you are correct in that i am over exposing with fresh chemicals its most likely faster than i was thinking.

    I am going to try again today this time i will be a big more gentle with the film layer. I think I am tearing it when i fix it. my agitation is more like paper not being delicate for the collodion. I am see that the collodion really is not stable until it is varnished ? I do not recall though would a negate image be varnished ? As i was writing this i went back and looked at my test plates and maybe they are not as bad as i thought so its just fragile until they are fully dried. so I am maybe to rough with the wet image.

    Are you referencing a book ? is there a better source of reading the John's book or notes? I will be honest i have not read the entire thing so maybe its time to do a bit more reading. I am going to try a few more today and see if I can get a better result.

    David

  5. #5
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    The glass cleaning agent is just used for cleaning, not to form a surface for the collodion to grip. A dirty plate will have nuclei where artifacts will build if the plate isn't immaculatey clean and those areas will cause problems. When you roughen the edges of the plate, the collodon then has a surface to cling to. I use a whetstone to roughen the edges but you can also use sandpaper. I'd rather not have my hand rubbing paper against a sharp glass edge. Sharpening stones are fairly inexpensive.

    Not all salted collodion formulas are so fragile that they rip easily. The ones without cadmium salts hold up better during processing although normally you wouldn't have a problem, especially if you subbed the edge with albumen. But the other formulas don't have the extended shelf life a cadmium-based collodion will have. Formulas containing potassium salts only are probably the least likely to rip IME. I've also recently read that the Ostermans don't recommend air drying the plates at ambient temperatures. They use a heat source (alcohol lamp IIRC) to immediately dry the plates after final washing. Apparently the slower air drying has a tendency to make the collodion shrink thus leading to it ripping after processing.

    If you get plates that look out of focus with the Brownie, remember that the film normally is located above those rollers, not between them. I don't know if that will be a problem for you, but I've epoxied aluminum corners in mine to help keep the focal plane as consistent as possible.





    I think John Coffer's book and dvd set are the best available although I have not seen Quinn Jacobson's new book ("Chemical Pictures"?). I would rank his original volume right after Coffer's. The Osterman's have a good chapter in Barnier's "Coming Into Focus" book.



 

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