Light source for contact prints

Discussion in 'Large Format' started by michael grace, Nov 3, 2002.

  1. I just bought my first LF camera - an Ebony RW45 - a great camera. I
    want to make contact prints but do not have an enlarger. Question is
    what can I use for a light source and how do I determine expousure
    time other than a test strip? Is easel best way to hold the
    negative? I have reading a lot of the postings - thanks for the
    education and response. Michael
     
  2. The best place for you to go to learn about contact printing is the "AZO forum" at www.michaelandpaula.com There you will learn everything you need to know about this meathod of photography.
     
  3. Michael, I use a painter's light. Not the fancy hot ones but the garden variety kind from the hardwarestore, about $3.95 with a spring clamp attached. An ordinary G.E.Soft White bulb 150 watts works. I clamp the light to a towel rack in my daughter's bathroom so that it shines on a T.V.Tray table. I plug the painter's lamp into a darkroom enlarger timer so I can get repeatable times. The old metal Gra-Lab is nice(and cheap on *b*y) but large. Kalt made a smaller one out of bakelite. I thing it was the cheapest one you could get new in the '70s(I know because I bought one) For a safe light I've had great results with a G.E.Guide light. They sell them two on a card for about a buck at Walgreen's(it's a night light, just plug it into a socket) To hold the paper I get the best results with a small piece of glass table top---they sell 'em at import stores like Cost Plus---resting on a piece of neoprene rubber matting about 1/2-1" thick. You can get it at any good hardware stoe. Sandwich your neg and paper between them. To determin exposure, I have a Kodak exposure guide, its a little plastic target with pie shaped wedges of different densities. I don't know if Kodak still makes them but I'm sure somebody does. It is a set up that works for me. Good Luck!
     
  4. You might try getting a Ziatype kit from Bostick & Sullivan. Get it with the platinum printing paper they recommend. Then you can hand coat the paper & expose by sunlight or fluorescents if you want. A nice way to go and you can still use your contact printing frame for Azo contact prints. I have found that a number of people who look at 4x5 silver contact prints & think they look small get a whole different impression when the same neg is done on a hand coated Ziatype, especially when coated by brush & the brush marks show. A whole different feeling.
     
  5. I take it that you want to look at the pictures to evaluate them. (If you intend these contact prints to be the final prints, check with the links mentioned in the other answers.) In that case a very simple setup will do. As a lightsource a normal lampbulb in a holder and possibly a timer connected to that. (Ordinary darkroom light is also nice.)<br>
    A piece of relatively thick glass (6mm or 1/4") will press the negative to good contact with the paper. You can order that from the nearest glass shop for a couple of bucks/euros(?). You can also make a simple frame out of wood with a bottom board where you use some kind of strong tape at one end to hinge the glass.<br>
    Finally, see to that you keep the lamp at the same fixed distance from where you put the neg/paper-sandwich until you know for sure that your exposure times are too short or long.<br>
     
  6. I'm very new to the whole technique - shooting, film processing
    and printing. But I did my first and second contact printing
    sessions this weekend. The first attempt I used a 20W halogen
    lamp about 30 inches above the neg and paper, and for
    exposure times down to 10 seconds found nothing but black,
    borders, picture area and all! I thought I might have the paper
    backing up rather than emulsion up and turned it over, with the
    result that the damn thing printed through the backing and gave
    me a terrible, but perceivable image.

    Sooo... I found a 7.5 W incandescant lamp (domestic night light)
    and put it into an angle poise lamp 36 inches above, and
    exposed for times between 20 and 35 seconds. The result was
    not a gallery piece, but not so bad for a greenhorn. I'm using Agfa
    Multicontrast Premium MCP 312 RC.

    The thought of a 150 W lamp seems out of the question to my
    way of learning to contact print. What am I doing wrong (or right)?

    It is frustrating when many instructions re contact printing start
    "using your enlarger as a light source.." when you don't have
    one!!

    Regards - Ross
     
  7. Part of the trouble is that you are using a bar ebulb that puts out a lot of light with enlarging paper that require very little light (enlarging papers are much faster than contact printing papers). Order some Azo from www.michaelandpaula.com. Azo is the last of the contact printing papers - its a slow emulsion with an incomparable scale - the bulb will work fine with Azo. If you insist on using enlarging papers for your contact prints, use a low wattage bulb (something like a 15 or 25 W bulb) but keep the bulb further away from the printing frame (I would suggest about 10 feet away). Adjust the distance to get printing times of about 20-30 seconds (that amount of time will give you enough room to play with dodging and burning). I would urge you to give Azo a try though. Cheers, DJ
     
  8. Forgot to add - the best way to hold your bulb is probably in one of those aluminium reflectors (available at any hardware store for a few bucks) - they come with a clamp that you can use to secure the reflector on a shelf or any convenient ledge etc. Also, another advantage to keeping the light further away from the printing frame is that it ensures even illumination at the corners of your printing frame. With the light just 2-3 inches away, it is quite likely that you have greater light in the center than the edges (I've found as much as half a stop differences, quite perceptible in a print). Cheers, DJ
     
  9. In mentioning ziatype prints I am thinking you will be doing 'final prints' from your contacts. Though not enlarged, if you mat & frame them you will have some excellent images (if your vision is up to it) that give all the negative is capable of. This is a good complement to printing with Azo for contacts. Two very different looks, each with their strong points.
    003z3n-10096484.jpg
     

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