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  1. #21

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    Quote Originally Posted by Jerevan View Post
    Note: I am not making calotypes (yet) but have you read Richard Morris' article in Coming into Focus? I suppose you know what a buckle brush is, but in case not, it's basically a small plastic or glass pipe with a wad of clean cotton in one end. It is necessary to use this tool, as this process seems to be very dependent on cleanliness and not getting things contaminated. Hope it helps in some way.
    thank you very much... I'm so sorry that you had to copy all that text from the Coming into focus chapter on Calotypes. I have the book right here and in fact I wrote to Morris (I found his email address on the internet).

    My main ources for alternative photography are Coming into focus edited by John Barnier and The book of alternative photographic processes by Christopher James. I do often add readings from the internet to expand my knowledge about a single process, like the Greenlaw PDF notes I linked in a previous post in this thread.

    I started using a "buckle brush" for Calotypes and I find the idea quite effective for such process. It's only downside is that loads too much chemistry compared to a regular brush.

  2. #22
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    Ah well, Fulvio, I figured that out, when re-reading the thread again!

    For future reference, I'll leave my write-up exercise in the earlier post. But from what I read of the experiments you are doing, it seemed that you don't use the recipe in the article?

    If I were you, I'd stick to one recipe (whichever you choose), use the same techniques you've used and just change the paper type at first.
    “Do your work, then step back. The only path to serenity.” - Lao Tzu

  3. #23

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    I still haven't got a negative...

    the problem remains development of the negative:

    whenever the developer (gallic acid with a very small quantity of silver nitrate and acetic acid) meets the silver iodide paper, this turns black, regardless if exposure occurred.

    I don't know if this is due preparation of the iodized paper. To reduce this possibility, I've tried several methods to obtain a iodized paper. Most manuals, including the Morris article in Coming into focus, only describe one.

    A) Talbot method: first coat paper with silver nitrate, dry, then immerse in potassium iodide solution. Paper needs to be washed to remove excess potassium nitrate; sources indicate "several hours" of washing, but probably 1 or 2 are more than necessary; permanence of the paper into the bath of potassium iodide is uncertain, some sources mention 2-3 minutes while others 20 to 60 minutes. After iodized and dry, the paper is coated with a sensitizer. But then, at this step and even before exposure, my papers have always turned black. I never came any further with this method, that is probably the most cited in modern books, which do not mention the following ways of making a iodized paper.

    B) No-pre-silver method: instead of coating the paper with silver nitrate first, one can directly immerse the paper in a solution of potassium iodide. Additives such as potassium bromide or elemental iodide may be used (I haven't yet understood what for). Since paper does not contain any silver at this stage, it doesn't require washing. After iodizing step is complete, the paper is hang to dry and then coated with silver nitrate. Immediately after coating, it has to be socked in clean water for 2-3 minutes. A precipitate forms and the paper is washed. Now you have a washed sensitized paper. My papers didn't turn black at this stage like they were with the Talbot method. But I had the only partial success here, being able only to photograph a neon light bulb (two times, with 10' and 20' exposure). I wasn't able to expose anything else (at the end of this post I'll explain why).

    C) Washed precipitate method: whatever method is chosen, the point of iodizing a paper is to create a paper containing silver iodide, especially in its surface. One can form such chemical directly on the paper, like in the previous methods. But one can also prepare the chemical away and later spread it onto the paper. Just mix two solutions of silver nitrate and potassium iodide in equal amounts. A precipitate forms and sits on the bottom of the solution. The top of this solution (its liquid part) contains nitrates and potassium which have to be removed and replaced by fresh distilled water. You can do this by decanting the solution several times. It is very easy to do. After the precipitate is cleaned, potassium iodide is added until it redissolves in a very milky solution. This solution is spread onto the paper, which becomes yellowish. After it is dry, it is finally sensitized with silver nitrate. No washing bath is required as there should be no impurities in the substrate. This method produces same odd results as Talbot method and I wasn't able to deliver a successful print. If it worked, it would be quite practical and fast, as intermediate washing stages of the paper aren't required. As no-pre-silver method, it allows the paper to be exposed dry rather than slightly wet.


    By experimenting all these methods and trashing a few dozen of calotypes, so far I understood that there's something wrong when silver iodide, gallic acid and silver nitrate are combined together in this process. With Talbot method I've been unsuccessful because it adopts a sensitizer made of such components. It acts like a developer and in fact turns my images black. With the other two methods, one can sensitize the paper with silver only, hence it doesn't turn black in the sensitizing stage. It will do in the developer stage, where gallic acid is always prescribed.

    The books and other sources suggest a developer made with a saturated solution of gallic acid (a merely 1%) and a lesser amount of silver nitrate and acetic acid in proportion. Even though, I've strongly reduced silver nitrate as suggested by the books: only by doing this I was able to deliver the light bulb photograph. This also allowed me to understand the following: no silver nitrate in the developer won't produce any picture; even a little quantity of silver nitrate will develop a picture, but will also turn the whole thing black, slowly or rapidly, depending on the quantity of silver nitrate. If there are any strong highlights in the image (like in the light bulb image I had), there's a chance that this will develop very fast compared to the rest, thus one can stop the development earlier by tossing the print into fixer. Otherwise it will progressively turn completely black (the speed depends on the quantity of silver nitrate in the developer). In any case, the "development" takes place in a few seconds to a few minutes, which seems too fast if compared to what is described in available sources (usually several minutes up to 1 hr).

    Is there any serious alternative to gallic acid developer worth trying? How about Pyrogallic acid?

    Jerevan: I always start with my books and then make modifications to improve if necessary. But in my case the process didn't work from the beginning and, yes, I tried different kinds of paper. Fabriano 5, Arches Platine, Schoelleshammer 6G, Zerkall Copperprint paper and a leftover from an unknown brand... I don't know, however, how much the paper can actually influence the outcome of a silver based process. With saltprints I can use either of the papers mentioned before without problems.
    Last edited by Fulvio; 11-09-2006 at 11:23 AM. Click to view previous post history.

  4. #24

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    Making calotype negatives

    Hello Fulvio, and others taking part in the discussion:

    I have been reading your discussion on making calotypes, and the lack of luck you are having, Fulvio. It is heartening to see that there are a few others trying this difficult and oftentimes exasperating process. After having made successful calotypes for the past 4-5 years, using a number of processes -- wet paper, dry paper, waxed paper; Energiatype; Diamond's precipitated silver process; LeGray's waxed paper; and of course, a variety of Talbotypes -- I have found, along with period practitioners, that Calotypy is not for the faint-hearted, requiring an obsessive attention to cleanliness and to detail, as well as to chemistry.

    So far you have been doing everything right to try and get a decent result, but the main problem which has plagued you right from the beginning is your choice of paper. The absolute worst kind of paper to use is anything which is described as "archival, acid-free" because the Calotype processes require that the paper be 100% cotton fibre, and slightly acid. "Acid-free" generally means that the paper has a layer of, or its pulp is mixed with, calcium carbonate. Calcium carbonate will cause the paper itself to react with acids (particularly acetic and gallic) and result in the blackening you are experiencing.

    Advice: stay with one formula (Greenlaw's is easy to start with), and use a 100% rag paper with at least a neutral Ph. There are very few papers which fit this need. I have experimented with dozens of papers, including some which I am trying now and which may be promising, and found that very few papers will work. They are: Crane's and Southworth's stationery, and tracing papers by Clearprint and Bienfang. The former two are thicker papers, use more chemistry, but have good wet strength; the latter two are thinner and sharper, but have terrific curling when wet and rather poor wet strength.

    Two recent Calotypes of mine will be seen soon (I am told) in one of the galleries in the www.alternativephotography.com website, as well as in their new book coming at Christmas. In addition, I will posting both Calotypes and their accompanying salted and albumen prints at my own website, www.VisionsInSilver.com, by the end of this year.

    Keep up the spirits! Of all the processes available for making one's own photographic images, the Calotype has to be the most exacting and difficult. Good Luck!

    Christopher A Wright

  5. #25

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    Christopher,

    thank you so much for the help! I knew there must have been someone around the world who tried this!

    Someone in this forum suggested the paper as a possible responsible, but my sources didn't explain what happens using a "wrong" paper. Ok, Morris and others suggest specific papers, but do not mention clearly the reaction I had with gallic acids and calcium carbonate. I thought the choice of paper was just a matter of negative usability for printing a positive.

    I called my art supplier and he has got a block of Crob' art paper by Canson. It is a kind of paper listed in that PDF article about Greenlaw experiments, so it should work for Calotypes. Unfortunately Strathmore, Southworth and Crane's papers can't be found easily here... I live in Fabriano land... but at least Canson, Arches and a few others are popular as well. If it's ok, I will stick with the Canson.

    Carbonates are detrimental also for Cyanotype process and for iron salts processes in general but I didn't assume it was the same for the silver-based calotypes (silly me I don't know a thing about chemistry). Anyway, for Cyanotypes is often suggested to immerse a sheet of paper in vinegar or a solution or citric or acetic acid to lower paper's ph and to get rid of the carbonate effects. I guess the same doesn't apply for calotypes...

    Again, thank you so much for the help. Will try the new thing as soon as possible and let know.

    best wishes

  6. #26

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    Success!

    it was indeed the paper...
    I got a block of 120 crob' art sheets for 10 euros... With one sheet I can make six 4x5" negs that makes a supply for over 700 calotypes

    It worked very easy this time. I used the Greenlaw variant, as the elemental iodine is useful to tell when the sheet is correctly sensitized.

    I'm attaching the scan of my very first calotype, including its digital inversion (desaturated). It was middle afternoon and there wasn't much available light. Yes, it's a bathroom, but that's the place with most light I could use in that moment... :rolleyes: Now imagine if Talbot first photo pictured his bathroom instead of a window....

    The exposure took 10 minutes at f8 with a 4x5" camera and a 90mm lens. The negative was dry when exposed and sensitized with 12% silver nitrate solution (1 drop of acetic acid was added each 5 drops of silver nitrate).

    Development required 5-10 minutes with gallic acid and small quantity of silver nitrate (every 30 drops of gallic acid: 2 drops of silver nitrate, 1 drop of acetic acid).

    Probably that scene called for 30' exposure if not more.
    Last edited by Fulvio; 03-02-2007 at 04:16 PM. Click to view previous post history.

  7. #27

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    this is totally different thing...

    Since the sunlight was over, I decided to move the camera in front of the computer and re-photograph an old image of mine... I just picked a random one

    Same kind of negative, exposure was 30' minutes, F8 with a 210mm lens.

    Development was quite longer, say 10-15'...

    This paper is really weak, doesn't tear apart in water, but it's difficult not to get traces and marks over it...
    Last edited by Fulvio; 03-02-2007 at 04:16 PM. Click to view previous post history.

  8. #28
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    Good to know that it worked out in the end, Fulvio! The second one of the photos looks promising.
    “Do your work, then step back. The only path to serenity.” - Lao Tzu

  9. #29

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    thanks Jerevan... that was actually a test, there's a long road ahead

    In fact, the new difficulty is now how to print such nice negatives.

    I tried salt printing and also a gelatin-chloride emulsion (sorta of self made POP). I can't post the scans because the "prints" are still wet.

    There isn't much to see anyway... The image won't print, at least under my usual UV lights. It is like the whole negative is shielding UV rays: there are black borders, in the sensitized areas outside the negative, but no image in the middle, under the negative.

    I thought it wasn't translucent enough, so I've immersed it in plain olive oil. After blotting, washing and drying the paper, I tried another exposure... The calotype now looks much more transparent and has definitively a better "negative look". But still, even after 1 hour exposure I haven't got a positive print. Salt prints and POP paper usually are ready in 5-10 minutes.

    Tomorrow is sunday and I will try using sunlight instead of artificial lighting. Maybe is the wavelength of my lamps.

    The negative highlights are yellowish in color; even though they look like transparent, perhaps the calotype wasn't cleared enough...

  10. #30
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    Congratulations!

    PE

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