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  1. #21
    Photo Engineer's Avatar
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    Friedman has published "The History of Color Photography" with many examples of alternative color photography. In addition, Leadly and Stegmeyer published a small book on color processes available in the mid 1900s.

    Jim Browning's dye transfers are superb. Ctein is also making beautiful dye transfers. Jim does them from slides, while Ctein does them from negatives.

    PE

  2. #22

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    3 COLOR PRINTING BY GUM

    Quote Originally Posted by Katharine Thayer View Post
    Hmm, I can't think who that would be. Don suggested Stephen Livick, but to my recollection, Stephen Livick hasn't been that stingy with information, has he? He gave an online course in gum printing through Bostick and Sullivan several years ago (was there a fee charged for that? I don't remember) and I think his website includes an illustrated tutorial on printing tricolor gum. I've disagreed with many of the categorical pronouncements he's made about gum, but I'm not sure it would be fair to say he's not been open about his methods.

    I've had a web page on tricolor gum in the works for over a year now, but I've moved twice in that time and spent considerable time between the moves looking for a house, as well as being sick a lot, so I haven't made much progress on that project; it's still sitting on the back burner. But hopefully once I get unpacked and settled and rested, I can finish that.

    Here's a brief preview: the introduction to my page on achieving color accuracy will say that it's not that difficult to achieve "good-enough" color accuracy using a variety of three-pigment combinations. Our eyes and brains have a remarkable tendency to read any color representation as an accurate representation, as long as it retains the relative hue relationships and tonal relationships of the original image. If what should be green is green, if what should be blue is blue, etc, and if the tonal relationships are proportional to the original, our eyes and brains say that's a good enough representation. However, if instead of relative color accuracy, the goal is absolute color accuracy where every color in the representation is an *exact* match of the color in the original image, that's an incredibly difficult task to achieve in tricolor gum, as I discovered when I started testing different color combinations to try to find the "best" pigment combination for color accuracy. But I'll save the rest of that discussion for my web page. In the meantime, I'd refer people to handprint.com, because Bruce MacEvoy has some good insights about this which are consistent with my own observations.

    Katharine
    please excuse me for resurecting this thread-but i think maybe you have all missed some things

    1. color separation by in camera negs or digital requires that you know what you are doing and where you are going

    other wise you are re-inventing the wheel and generaly you get wheels that don't roll

    any tech school training for pre-press before the desktop revolution could turn out people with the theory and knowledge

    running a 60x60 0r 30x30 flatbed and haveing to turn out the negs to keep a busy commercial printer on schedual for a couple of 10 yrs will give you the practical end

    remember that each 4/color needs 4 negs-cymk and each neg may need 3 exps-main, shadow flash, and highlight bump

    this kind of experience is directly applicable to all so called alt process "art" photography since these processes are in fact what is in use every day in any form of printing-screen, offset, litho, gravure etc, and these were at one time what was main stream photography

    so if you ask somebody who knows you might get an answer-IF YOU CAN GET DOWN ON THE GROUND AND OUT OF THE FANTASY DAYDREAMS LONG ENUF TO LISTEN

    pre-press- 4/c strippers, plate makers, camera operators etc all are working all day long every day with the standardized materials that were once consumer products for the photo trade and are now available to any one who knows what to ask for-BUT NOT AT THE PHOTO STORE SINCE TIME MARCHES ON AND NEW REPLACES OLD BUT NOT CAUSE ITS BETTER

    the point of this rant is that a 4 or 3 color print is a printing process and not 'photography' and color theory and its practical application is easy to get if you WORK at it BUT YOU MUST START FROM THE POINT OF SUCCESS

    ***get a pocket "printers pal" and the chapter on in camera color seps will start you from a proven place of success***

    if you can ignore all the blahblogery that sells the software and hardware that must be updated every 6 mos you can get results from your pc that will also work

    2. the inter-action of pigments with emulsion and sensitisers is so complex that if you don't start with a proven, standardized combination; or if you change anything and sub a new supplier etc you will get lost immediatly

    standardization is very difficult with gum arabic

    solution: DON'T USE GUM ARABIC ; OR IF YOU MUST, BUY A STANDARD COMERCIAL SOLUTION WHICH TAKES SOME OF THE VARIABILITY OUT OF THE MIX

    EX: saul the coffee man, in costa rica, sells some gelatine and/or gum granules that you can mix up yourself and since he is also a world class artist you know that it will work

    there are plenty of other substances that you can use instead of gum arabic and you can buy them in the 99cent store

    "there are no rules in gum printing" really means that you never knew the rules and you don't have the skills and craft-any high school chemistry class will give you all the tools you need to be able to repeat success, even if you failed chemistry class

    in 1976 i was the " tech" at the art dept of a college in a major university-that meant that while i taught the large format photo class, the tenured head of the photo dept got the very nice salary-so i went commercial and never looked back

    i was a "commercial artist" and a"photomechanical artist" and a "commercial photographer" and i also was hung in juried shows

    my day job was in the adv biz and at home i created "fine art" but now i am 100% dis-abled

    please feel free to avail yourselves of my experience

    vaya con dios

  3. #23
    AgX
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    z-man

    Photography and printing have been strongly connected over the history of photography and generations of photographers have employed techniques which fall under printing techniques and were not advised to go to a printer instead.

    Many photographers used several imbibition processes over history employing only three colours.

  4. #24

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    Quote Originally Posted by AgX View Post
    z-man

    Photography and printing have been strongly connected over the history of photography and generations of photographers have employed techniques which fall under printing techniques and were not advised to go to a printer instead.

    Many photographers used several imbibition processes over history employing only three colours.
    "photography" and printing by press and or litho stone or photogravure or photosilkscreen are of course 2 sides of the same coin

    my point is that a process camera operator could(and this one does) produce 3 color pigment prints , or mag +yelo over cyanotype or 6 color or what ever with complete consistency while asleep standing on his/her head

    since the photomechanical processes and mediums continued to develope technically in the printing trades , the attempt by fine art types to duplicate past processes are re-inventing the wheel since what was everyday in the store supplies 100 yrs ago are of course no longer there

    those emulsions and chemestries and techniques survive today in the printing industry with the modern equivilents of the old ingrediants

    if i know how to separate a full color subject into a cyan, yelo, magenta and black printer(neg) and if i know how to finese each separate neg with a main, shadow and highlight exp and i know the properties of pigment inks and how they behave when suspended in sensistized emulsions---

    how can a simple 3 color gum print be a big mystery?????

    of course if you don't know the simple mechanics of pin registration of multiple negs and overlays and compositing in a vacuum frame with, say, 10 separate negs---

    then i guess that eyeballing 3 negs into regestration and taping them down so as to get consistnt prints would be an overwhelming task that could only be accomplished by supernatural beings in mythical tales of old-right???????

    a digital photographer who prints out via an inkjet is actually a "printer" since that inkjet is actually haltoning the images ,and, since they were captured via a digital camera were never actually continuous tone at all, so rightly they are not photography

    but any continous tone "photographic" print must be converted to some type of "printing process" to be published unless you are only going on the web

    if a "photographer" would learn just the basics of any printing process, then any of the "alt processes" become transparent in technique

  5. #25
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    Quote Originally Posted by z-man View Post

    there are plenty of other substances that you can use instead of gum arabic and you can buy them in the 99cent store
    What are they?
    juan

  6. #26
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    I might note here that the purity of many of the printing inks and hte halftone process itself are partly the cause of the need for the 'k' in the c/m/y/k printing system.

    In photography, the continuous image, coupled with the less pure dyes add the 'k' component all on their own. Of course, there is always a tiny bit of retained silver in the dye image of chromogenically developed prints that contribute to this as well, making blacks black.

    I have to agree with z-man in his posts. Don't reinvent the wheel and come up with a square one.

    PE

  7. #27

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    COMO SE DICE "GLUE" EN ESPANYOL?

    Quote Originally Posted by juan View Post
    What are they?
    juan
    QUE TAL HERMANITO?

    EN LA TIENDA ESTAN TODOS

    try elmers for a start-i like "school glue"

    vaya con dios a todo

  8. #28
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    Quote Originally Posted by z-man View Post
    "photography" and printing by press and or litho stone or photogravure or photosilkscreen are of course 2 sides of the same coin

    my point is that a process camera operator could(and this one does) produce 3 color pigment prints , or mag +yelo over cyanotype or 6 color or what ever with complete consistency while asleep standing on his/her head

    since the photomechanical processes and mediums continued to develope technically in the printing trades , the attempt by fine art types to duplicate past processes are re-inventing the wheel since what was everyday in the store supplies 100 yrs ago are of course no longer there

    those emulsions and chemestries and techniques survive today in the printing industry with the modern equivilents of the old ingrediants

    if i know how to separate a full color subject into a cyan, yelo, magenta and black printer(neg) and if i know how to finese each separate neg with a main, shadow and highlight exp and i know the properties of pigment inks and how they behave when suspended in sensistized emulsions---

    how can a simple 3 color gum print be a big mystery?????

    of course if you don't know the simple mechanics of pin registration of multiple negs and overlays and compositing in a vacuum frame with, say, 10 separate negs---

    then i guess that eyeballing 3 negs into regestration and taping them down so as to get consistnt prints would be an overwhelming task that could only be accomplished by supernatural beings in mythical tales of old-right???????

    a digital photographer who prints out via an inkjet is actually a "printer" since that inkjet is actually haltoning the images ,and, since they were captured via a digital camera were never actually continuous tone at all, so rightly they are not photography

    but any continous tone "photographic" print must be converted to some type of "printing process" to be published unless you are only going on the web

    if a "photographer" would learn just the basics of any printing process, then any of the "alt processes" become transparent in technique
    Who makes negatives anymore? Isn't everything pretty much direct to plate now?
    Don Bryant

  9. #29

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    Quote Originally Posted by Katharine Thayer View Post
    But looking at Hans and Chia's site, where they offer printing services in "four-color" gum, reminds me again what I told the original poster in a private message the other night: pretty much without exception those of us who work in color alternative processes make our color separations digitally, output to imagesetter or to inkjet printer (and I believe that includes all of the links that were provided here, except for the link to the French site where the person is making analog separations and hoping eventually to make gum prints from them but hasn't actually done that yet). I can only think of a couple of people I know of who have done three-color gum from incamera separations using filters, and as far as I know, they did it only once or twice out of curiousity; the bulk of their work is done with digital separations.
    Katharine
    Back in the days when there was no digital I made quite a number of three-color gum and carbon/carbro prints from in-camera separations using filters, or in some cases from separations made from transparencies with an enlarger using filters. My colleague Sam Wang also did a lot of work in color gum with in-camera separations. It was very complicated work and controls were quite limited.

    Now that we have the computer and Photoshop to generate color separations I don't believe anybody in his right mind who is really interested in the final print, as opposed to ideology, would even consider wet processing color separations outside of doing so as a historical curiosity.

    Sandy King

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    [Moderator's Note: Unfair implication directed personally at another participant.]

    PE is right; the need for a k layer in the cmyk printing process was generated largely by the impurities in the process inks used, and I'll take his word for the halftone process having something to do with it to. Whether one can achieve a solid black in gum with three colors and three layers depends on the pigments chosen and the concentration of those pigments. But if "not re-inventing the wheel" means using process printing inks and commercial printing methods to print gum, I'm not really interested in that at all.

    Katharine
    Last edited by David A. Goldfarb; 06-28-2007 at 11:59 AM. Click to view previous post history.

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