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  1. #1
    timbo10ca's Avatar
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    Split Grade and contact printing

    This is probably a dumb question, but I have to ask it- sorry. When you are contact printing, do you approach it in the same manner as you would if projecting? That is, split grade printing for contrast and exposure control, dodging/burning, and whatnot? I'd heard that some people use certain types of lights because they give a sharper image than using a diffusion enlarger head, and you want to try to use a minimum exposure which is quite long to get full paper response.

    Thanks,
    Tim
    If only we could pull out our brains and use only our eyes. P. Picasso

    http://www.timbowlesphotography.com

  2. #2
    wilsonneal's Avatar
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    I use a D2V enlarger with Ilford MG filters above the condensors and project a circle of light on my contact printing frame when doing 8x10 contacts. I have started using the split grade techniques and am really pleased with the results. I think it's a technique that has a lot going for it. I also burn and dodge using this technique.

    I don't think that the length or shortness of the exposure could have any bearing on full paper response. I don't know the science behind that concept, but I am open to hear from others who know more.
    Neal

  3. #3

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    I too used split grade contact printing for my 8x10 negatives before I got hooked on Azo. I used the Zone VI 4x5 VC head. Since you are doing contact printing, the type of light source should have absolutely zero impact on the print sharpness. What will impact print sharpness is the quality of the contact between the negative and paper. I would recommend a good quality (I use a Bostick and Sullivan) printing frame or a vaccuum easel.

    Good luck and have fun,

  4. #4

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    Light Source Affecting Sharpness in Contact Printing

    Quote Originally Posted by jgjbowen View Post
    Since you are doing contact printing, the type of light source should have absolutely zero impact on the print sharpness.

    Good luck and have fun,
    Forgive me, but this is not an entirely accurate statement. A point light source such as Nuarc 26-1K or Olite unit (normally used for alternative process contact printing) will give a higher acutance of the image than a diffused light source such as fluorescent tubes or a light bulb in a reflector. I will admit I am splitting hairs here but it does make a difference if there is a slight scratch in the negative, dust embedded in the negative emulsion, and especially for a scratch in the glass. The reason is the directional nature of the light. A point light source or to some extent a collimated light source such as a condenser enlarger produces very directional parallel rays of light which will exaggerate a scratch either in the negative or glass. A diffuse light source has rays of light striking the negative from many directions and will tend to blend the edges of scratches and dust. I realize I'm talking more from an alternative process perspective, but the same does apply for contact printing onto silver gelatin. The difference in a silver gel contact print is minimal so you really don't need to be concerned about your light source. It does make a larger difference with projection printing. It also makes a big difference in alternative processes and it does make a difference if you are dodging and burning with a card over the top of the contact frame in either process. With a point light source, the light does not wrap around the edges of the card. However, the light will wrap around the edge of the card in an exposure with a diffuse light source and thus feathers the edge of the dodge/burn. This concept was originally introduced when cold light heads came out decades ago and the justification was to obtain better print quality with diffuse light sources. At first I thought it was marketing hype, but after purchasing a cold light and working with it, it is true that dust and scratches are not nearly as prominent. My alt process experience has confirmed the same holds true for contact printing, although the effect is not nearly as pronounced.

    Bob Herbst



 

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