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Thread: Color Correcting Scanned Color Negatives

  1. #1

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    Color Correcting Scanned Color Negatives

    I'm interested in the different methods that people use to color correct scanned color negatives. In the past, it's always been difficult for me to get good results. However, I've recently been getting some nice results using a different method.

    In brief, I been using a minimum of adjustments in the scanning phase. (I'll use some adjustment of the left and right input Levels sliders.) Once ported to Photoshop, I've been using a levels adjustment layer to correct color. Doing each color separately, I bring the left and right sliders to within some tasteful distance of the ends of the histogram for each color. (Recall that the drop down menu slecter at the top allows one to adjust each R, G, B color separately.) Then, I alter the center gamma sliders for each color to obtain the color balance that I want. Occassionally, I'll use the white point eyedropper to snap the image to a selected color of white. (If I see a decent color of white in the image.) I've been using Epson Scan. I usually prefer Silverfast for their preselects for different brands of negatives. But, Silverfast stopped working on my Mac. (When I reformat, as I do periodically, it will work again.) None the less, I've been getting good results using Epson Scan. I'm not suggesting that my selection of this process is the result of any deep thought process. It just seems to work well for me.

    I previously used a Color Balance adjustment layer. For me, this approach just didn't work well. I went nuts trying to get good color balance using this method. (Maybe that's not such a long trip!)

  2. #2

    Re: Color Correcting Scanned Color Negatives

    Just a short answer, since it is late. Normally I work on a copy of the file, instead of using adjustment layers, though it is only a personal preference of the way I learned this; not against adjustment layers, just don't use them so I keep file sizes reasonable; besides History palette helps get rid of steps when needed. Usually do adjustments through Hue/Saturation, while watching HSL sliders on info palette, with Gamut warning on, and using CMYK preview. Of course, this varies depending upon CMYK profile, where the image will be sent, what imagesetter or press profile, and various other factors.

    Mostly I look at the numbers more than visually, though it helps to have your monitor close. I have worked on a few really nice monitors, with puck set-ups, though quite often have found myself on crap monitors (or on a laptop). Due to that common working so-so monitors, I have learned to view colour numbers, look at channels, and understand how different percentages of cyan, magenta, yellow or black combine to create certain hues. This probably sounds horrendously complicated and strange to most people here. In over ten years of commercial printing I have never had a job turn out to be off in final colour rendering; I should point out that I have only used dye sub or inkjet prints for proofing.

    You will probably want someone else responding more specifically to remaining in an RGB workflow, and outputting to some sort of Epson printer. With scanning, I have used several versions of SilverFast, and sometimes I find that the preview image gets me close to what I want to see in PhotoShop, though often I find a need to do slight adjustments. When I have used oXYgen for scanning, then I have found I rarely need to do any adjustments in PhotoShop. That might be the difference in going towards high end scanning software, though I do think SilverFast is very good software.

    Ciao!

    Gordon Moat
    A G Studio

  3. #3
    bob carnie's Avatar
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    Re: Color Correcting Scanned Color Negatives

    I bring the scan into a very *middle groung balance* for the colour in the image.I prefer to keep the image on the flat side with as much information as possible. Each step of the process from the scan forward will lose info at both ends, as Owen spoke of in another thread here.
    In PS I use the adjust for contrast density first, then adjust the colours in colour balance layer. I pay attention to elements within the image and will try to use complimentary colour adjustments in the shadow, highlight and midtone. This will create the starting point of colour contrast and separation that I want to achieve in the final image.
    From here I will give a pre determined amount of saturation depending upon which printing material I am using. I find cibachrome needs less saturation then say inkjet rag or Fuji Matte paper.
    I really like select colour adjustment and will use this pallette to darken lighten colours , enhance colours to balance against each other. This again will be a judgement call as the foreground colour may be rich in red and the background colour green, *when adjusting the greens for the background colour I will add more cyan than yellow which will creates more separation as cyan is the complimentary colour of red*
    Sounds confusing, I have a colour wheel at all my workstations to quickly refer to so that when mixing the colours I am aware of logical complimentary colour enhancements.
    We are testing on each paper a colour ring around and then with this select colour making huge adjustments to see the breaking off point of each paticular emulsion's response to colour in the final print.
    After this I will use selective sharpening or dodge/burn, If I hit all the right notes in the above the dodging and burning is minimal.
    Luckily I was forced to memorize the colour wheel in College and each lab I worked at since I have made colour ring arounds to really get a handle on colour adjustments. Now with PS the control is steroid quality and one has to be careful not to take it to far..
    It is helpful to do some of these colour test of known images of coloured objects onto your materials of choice.
    The film or final printing material you may be using may not be capable of reproducing the colours and all the work in the world will not help reproduce certain colours and or subleties of them.

  4. #4
    Resident Heretic Bruce Watson's Avatar
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    Re: Color Correcting Scanned Color Negatives

    George DeWolfe wrote an excellent book: Digital Photography Fine Print Workshop in which he covers the topic of color correction. His methods are fairly straight forward and they work well for me.

    Bruce Watson

  5. #5

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    Re: Color Correcting Scanned Color Negatives

    I use Vuescan for scanning. It has a useful feature. If you right click anywhere in the image, it sets that to a neutral gray of the same intensity and adjusts the rest of the image appropriately. This is particularly useful if you can manage to put a gray card somewhere in the scene. Later in my photoeditor---I prefer the Gimp---I make further adjustments if necessary. I mainly use the curves tool. I adjust the value (combined RGB) curve, and each of the R,G, and B curves separately as needed. I try to find highlights, midrange, and shadows which should be neutral and adjust the curves appropriately. If, for example, the low values were too blue while the high values were too yellow, I would lower the blue curve at the low end and raise it at the high end. You can do something like this using the levels tool, but you get much better control using the curves tool.

    If I can't find any neutral areas in the image, I use some other reference colors, such as blue for the sky, where I've found certain values are appropriate. For portraits I use reference values for R, G, and B, but often these need to be adjusted according to the skin color of the subject.

    What you do with the levels tool. i.e., first making sure that each of R,G, and B extends over the full range and then adjusting gamma for each of them, often works, but in some situations it won't. For example, it is quite possible for a scene to be concentrated in one color or another at one end of the scale and the range for that color should not be expanded to fill the entire range.

    One thing to keep in mind it is that, as Dan Margolis points out in "Professional Photoshop", it is usually impossible to get all the colors right. For example, in a scene involving both shadows and sun, the latter will be blue compared to the former. You can sometimes deal with this by applying different color correction to different areas of the image, but that can get pretty cumbersome. Margolis says that you should concentrate on getting the important colors right and not worry about the others. I've found that to be good advice.

  6. #6

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    Re: Color Correcting Scanned Color Negatives

    I also use the technique described by Leonard Evans; it generally works very well. The technique is also desribed in Martin Evenening's Photshop for Photographers. In addition, I will sometimes use selective color to tweak narrower color ranges in the photo.

  7. #7

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    Re: Color Correcting Scanned Color Negatives

    I also use the technique described by Leonard Evans; it generally works very well. The technique is also desribed in Martin Evening's Photoshop for Photographers. In addition, I will sometimes use selective color to tweak narrower color ranges in the photo.

  8. #8
    Michael E. Gordon
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    Re: Color Correcting Scanned Color Negatives

    I, too, exclusively use Curves.

    Although it's permanent, you might be amazed at how well Auto Color (Image>Adjustments>Auto Color) performs with certain images that need significant initial correction. The permanent changes are irrelevant if nothing clips and it gets the image in the color-correct ballpark. Auto Color can be a real time-saver.

  9. #9
    tim atherton's Avatar
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    Re: Color Correcting Scanned Color Negatives

    NegPos (which you can still get, but you need to hunt it down) and it's simplified sibling ColorNeg work really well - especially if you go to the extra step of calibrating it for whatever colour neg films you use (although I mainly use them for b&w).

    You need a 48bit raw scan to start from

    http://www.c-f-systems.com/Plug-ins.html

    http://www.c-f-systems.com/ColorNegs.html

    http://www.c-f-systems.com/ShortVersion.html
    You'd be amazed how small the demand is for pictures of trees... - Fred Astaire to Audrey Hepburn

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