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  1. #1
    qwfwq's Avatar
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    A Few Questions About Photogravure

    Hi, looking to start learning this process. I've done large format photography and intaglio for years, so I am not completely new to either process, but need to sort out some issues before I buy things.

    1) Does the aquatint dust go on the plate before or after the sensitized/exposed tissue is applied to the plate? I can't find anywhere that says certainly what way is best, and also that pine rosin is sensitive to the alcohol in the developer(?), and I'm supposed to buy some brand name "PICCO" stuff. Does it matter what order it goes in? I have plenty of access to pine rosin and a nice old coffee grinder, and would prefer to use what I have.

    I would image it would be easier to work with if you could apply the gelatin first so if you mess up the exposure you don't also have to redust and melt the plate every time. Probably easier to apply it to the polished metal than to a layer of melted rosin? But, from what I understand, its the aquatint layer that actually makes the image, therefore the final etched plate would be less sharp if the aquatint was on top of a layer of gelatin (kinda like the concept of 'emulsion to emulsion' when contact printing)...or am I looking too far into this?

    ~~~~~~~~~ resist
    *********** aquatint
    =========plate

    OR

    ***********aquatint
    ~~~~~~~~ resist
    ======== plate


    -----------
    2) What would be a good source of UV light for someone who can't have a big "bank" style set up? It'd be best if I could use a cheap flood light or something...I dont mind longer exposures and the biggest I will be exposing is 4x5 to 8x10. If I ever get to the point (of insanity) where I think going bigger than that is a good idea , I'll get a proper unit together. Just looking for something that'll work for starters.
    ------------
    3) How long in general would the exposure with said light source be? Are we talking seconds? minutes? hours? I don't expect a exact number, just something to go by.
    -----------
    4) Is there a cheaper place to buy the pot.bichromate? bostick has it, but there is a bunch of hazmat, etc. Would it be possible to buy somewhere locally? Or is it a specialty kinda thing?
    -----------
    5) Lastly, has anyone had any experience with the gelatin tissue from B/S? Just want to know if its generally of good quality (really don't want to add anything to the list of possible **** ups. )

  2. #2
    samcomet's Avatar
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    qwfwq - if you were interested in using solarplate photopolymer technology, which is non-toxic plate making, I could give you a run down of my work flow...
    cheers,
    sam

  3. #3
    Hexavalent's Avatar
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    Quote Originally Posted by qwfwq View Post

    1) Does the aquatint dust go on the plate before or after the sensitized/exposed tissue is applied to the plate? I can't find anywhere that says certainly what way is best, and also that pine rosin is sensitive to the alcohol in the developer(?)
    The aquatint should go on the plate, which is then baked to 'set' the dust, and then finally the gelatin transfer. Alcohol will melt traditional rosin dust. Some practictioners use laser-toner powder, acrylic spray paint, or even a fine mist of acrylic floor-wax as an aquatint. A double exposure of the gelatin with both the image and a stochastic screen can also work.

    Is there a cheaper place to buy the pot.bichromate? bostick has it, but there is a bunch of hazmat, etc. Would it be possible to buy somewhere locally? Or is it a specialty kinda thing?
    If you think that dichromate is expensive, have you looked at the price of high quality copper for etching?
    - Ian

  4. #4
    Ross Chambers's Avatar
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    Is solarplate truly photogravure? No criticism Sam, I've seen some very fine prints from solarplate and like it a lot. However a recent exhibitor at the local art gallery in Springwood displayed "photogravure" prints which were made via solarplate. Another local at another local show exhibited prints of predominantly photographic origin and described them as solarplate. Both were excellent sets of prints, it's just that my understanding of photogravure was that it was a rather more virtuosic technique.

  5. #5
    samcomet's Avatar
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    G'day Ross...no criticism taken (I am far too old to take things in the negative!!!) I can only say in answer to your question that everything that I have read over the past few years has told me that photogravure, while invented by Fox-Talbot, has at its base definition, an intaglio etching process where the inked plate transfers a photographic image to a receiver paper. I have not seen the definition of the process defined by the nature of the plate (copper, polymer or otherwise) nor the means of etching (acid v.s water). In both solar plate and copper acid etched the plate is exposed by UV light. The intaglio process however seems to be part of THE definition i.e. an etched plate in negative holds ink in its valleys or etched out parts and through a half tone process transfers a full tone image to an un-sensitised piece of paper. The half tone being produced in a variety of means: dust, dot screens etc. etc. The image on a solar plate or copper acid etched plate can come from a positive film/acetate/ or other medium but for it to be called photogravure I guess it needs to be originally a photograph. At least this is what I have come to understand....that being said I am more than willing to admit ignorance in this department - please enlighten me if you will if you have another perspective. Always willing to learn!!! I've been making what I call photogravure prints via solar plates from my negs for several years now and it would be good to know that I've not been calling the process by the wrong nomenclature. Anyway Ross if you are in town next Saturday, 26th and in the vicinity of Clovelly I have an exhibition of some of may latest work opening at Gallery East 21 Burnie St. with drinks from 3 til 6 pm. These, I need to point out, are not my etched work but straight out neg to print. URL:

    http://www.apug.org/forums/forum214/...n-26-11-a.html

    Anyway cheers for now!
    sam

  6. #6
    MDR
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    Please excuse my ignorance but isn't a photogravure as the name implies a gravure/Intaglio (German Tiefdruck) technique whereas solarplates have more in common with Offset printing or Lithography (Flat printing/Flachdruck)? If that's the case they are completely different techniques and their names are not interchangeable.

    Dominik

  7. #7
    samcomet's Avatar
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    G'day Dominik - To the best of my knowledge the word intaglio refers to inking a plate whereby the ink falls into pits and grooves and valleys of a plate formed by the etching process. Excess ink is then wiped away from the hills and peaks of the plate. When I use solar plates, post exposure and washout, I roll ink onto the plate and wipe off the excess leaving the ink in the ruts and valleys of the plate and then print. In the offset or lith process the plate is covered with a substance that holds dampness (water). This substance is turned into an image by projecting UV light through an acetate negative (or positive) and washed out/cleaned in places where the UV does not allow the substance to harden....in other words a thin emulsion of polymer or wax is made on the surface of a plate in negative to the image required. A damp roller rolls over the polymer to coat it with water (which does not sink into the valleys) and then ink is applied to the whole plate - but the ink does not stick to the water damped part of the plate but does stick to the valleys of the plate itself. The ink is then transferred to the paper as a positive. The difference being that the ink in intaglio etching is physically/mechanically removed from the areas not wanting to be printed. In offset or lithe it is a physical/chemical reaction the prevents the ink from adhering to the parts of the plate that are not wanted to print. This chemical reaction of ink and water not mixing is, if I remember correctly, is called hydrophilia or hydrophobia. A further part of offset process is that the ink is transferred to an intermediate sheet or receiver before being pressed onto the final paper for printing. The resultant image is reversed and must be accounted for when making the offset plate. Anyway that is what this old fading memory of mine thinks but like I said I am always prepared to learn new tricks or to be corrected !!!! Thanks for the observation and again I am well prepared to be wrong here. cheers, sam

  8. #8

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    1) The hardest things to learn in photogravure from hardest to easiest: Aquatinting, etching, printing, exposure. The aquatint can go either way. The problem is once you adhere the gelatin to the plate you have to use alcohol to remove water from the gelatin quickly so you won't get uneven drying. If you want to put the aquatint under the plate you have to use something that is not soluble by alcohol. The old fashioned way is to use asphaltum which melts at high temperatures 400-450F, creates very high resolution(equivalent to 350 dpi) and does not dissolve with alcohol. The difficulty with asphaltum is that it's greasy, so it has to be treated. Additionally if you use an under the gelatin aquatint you have the problem of peeling as it's very difficult to get the gelatin to adhere properly without specialist equipment, like a mangle to squeeze the gelatin onto the plate.
    PICCO is wonderful, it can be used under or over the gelatin, it melts at a precise low temperature (around 225F)and it can stay melted in perfect little spheres all day without evaporating or fusing with other particles, you can use it under the gelatin because is not soluble by alcohol, and the resolution is pretty much the most resolution that can be gotten from any ground.

    The easiest way to learn is to do a secondary exposure with a screen. The best screens are from Mark Nelson from http://www.precisiondigitalnegatives.com Look in the front page for his email and sent for some. They are expensive, but great. The coarse or medium density both work fine. The best book for this is http://www.amazon.com/Copper-Plate-P.../dp/0240805275 , you don't need to get anything else. All the info you need is there. There are lots of opinions as to what is better over or under, but think about this, Jon Goodman is the acknowledged master of the medium today, his work is stunning and he uses the over method.



    2) A big bank of tube uv's is fine, again some opinions on this(point vs diffuse), but I have not seen any proof either way. And you have to get or build a vacuum frame. No, there's no way around this, don't even try.

    3) My exposures are around 250 units with a light integrator. It's almost like 250 seconds, but not quite, because integrators measure light output not time. And this is the only sane way of doing this, I repeat, get an integrator, you'll thank me later. The book I mentioned earlier tells you how to test to get in the ballpark.

    4)B/S or Photographers Formulary. Don't even try to get it somewhere else, and once you decide to get it from someone, don't change suppliers. Again, trust me on this.

    5) I would use Phoenix from http://www.capefearpress.com/ instead. Better, more flexibility as far as size and the material has been around longer.

    Prepare to spend many thousands of dollars and years perfecting the process, it's frustrating, but very rewarding. I would attend a workshop from either Jon Goodman, CrownPoint Press, Cape Fear Press, Renaissance Press, or Lothar Osterburg. Learn the digital way of doing positives, the best system is Precision Digital Negative, but beware. If you use that system you have to pay royalties if you sell prints(Yes, I was shocked too)
    Good luck

    P.S. Solar plates are not photogravures, can never be. Renaissance Press teaches a system with polymer(not solar plates) that it's getting really, really close to the real thing. But for the real thing(as of this writing) there is no substitute for Copper Dustgrain Photogravure.

    P.P.S. I want to be clear about this and not sounding like an ass, but you express some concern about cost in one of your materials. You can not do photogravure on the cheap. It just isn't possible because shortcuts just cost you money. Follow the instructions, don't deviate and you'll enjoy it and create beautiful prints.
    Last edited by squinonescolon; 11-21-2011 at 07:24 AM. Click to view previous post history.

  9. #9
    qwfwq's Avatar
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    squinonescolon:

    Thanks for the reply. I know what I am getting myself into, and I'm not trying to do this on the cheap, there's just a lot of people that claim they have the best product and I don't want to pay more or less if there's something that is considered to be of standard reliable quality. Cut once measure twice with the old debit card, ya know?

    I have access to presses, lights, acids, vents, hoods, beakers, gloves, masks, burnishers and scrapers, trays, plenty of copy films and developers (would pyro be good to use for this?), a few good copper plates (to ge started with (gotta keep that scrapping hand strong!) and metal polish, etc etc... along with assistance from those who have done this before. oh and all the inks I want. Basically, a fully equipped intaglio shop and b/w darkrooms.

    Would a vertical etching tank work better for this? Most people seem to use trays so you can inspect etching, but I've always used a vertical tank for etching copper. I'll need 3+ baths...so I guess my one vertical tank won't be getting used for this...

    Is it pretty easy to tell once the aquatint goes on, the gelatin is adheard, exposed developed and all that, right before it gets etched if the plate will etched properly? Will all the highlight and shadow detail be present and what not? Basically, does the plate display the tones and details that will etch or is this one of those "well maybe, it takes experience to read it" sort of things?

    ...and I've tried solarplates, theyre ok, but I wasn't thrilled with it. Also, 11 bucks for every 5x7 exposure doesn't sound all that much cheaper to be honest. Id rather just toss the $3 worth of picco and tissue if I f*** it up. And lets be honest, copper plates are just way cooler.


    So do I just need:
    Gelatin Tissue (from Phoenix, right?)
    Pot. Bichrom (from BS)
    PICCO (from Phoenix)
    and the various other little things like ammonia, alcohol, patience, etc?

    (and of course some purty paper. Any suggestions?)


    -joe

  10. #10
    qwfwq's Avatar
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    also i got the "demystifying copperplate gravure" book. is that any good?


    can the sensitizing solution be stored until exhausted? I see 1 liter will sensitive one square yard or tissue. Or is it better to sensitize all of it and store it wrapped in foil in the fridge till I use it?
    Last edited by qwfwq; 11-21-2011 at 01:24 PM. Click to view previous post history.

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