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  • BW Copy Neg vs. Scanning Test

    How good can a black & white copy neg get compaired to a scan?

    I ran into an original that is very dark, almost can't see into the dark areas without a very good light. I have mentioned copy negs on this forum in the past and thought this would be a good image to demonstrate. The photograph also has a very heavy cracked texture with some slight silvering in those dark areas.

    Info on the attached example:
    -Print scanned RGB with no correction and no sharpening.
    -Copy neg made on 4x5 B&W copy film (polarizing filters on lights and camera) and the neg scanned with no correction and no sharpening.
    -the image size of the original photograph is 3x5, the image size of the section you see on the test was about 1 inch wide on the original image.

    Both images were scanned using Silverfast. If you have any suggestions or would like me to try anything to improve the scan of the print for a better comparison I would be glad to be directed... when I have tried everything I know it gets real contrasty with the damage almost hiding the picture.

    If anyone wants any advice on copying on setting this up with a film or digital camera just let me know.

    I wanted to post this because we find copy negatives very valuable, and I wasn't sure if some folks here didn't realize how good they can get, you can compare the sharpness of the scanned print (which you are already familiar because of your own scanning) to the detail in the image made from a copy neg.

    I don't know if this should be here or in tips?
    Hope this is intersting and helps, Roger
    Attached Files

  • #2
    Roger -- interesting example. Thanks for sharing your results.

    Jim Conway's thread on copy negs might interest you.

    Copy negs

    Comment


    • #3
      We can use all the copy techniques you can provide.

      Thanks.
      Learn by teaching
      Take responsibility for learning

      Comment


      • #4
        Hi Roger, we know that in theory film will deliver a better result if you have the ability to handle it well, while we also know that in theory a 'second generation' will not be as good as the original.

        Nice to see that the neg is the solution in this case.

        Chalk and cheese result, but if you did not have this ability, how much would it cost and how hard would it be to find someone to make a copy neg for you (forgetting the digitizing aspects)?

        Stephen Marsh.

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        • #5
          Hi Roger,

          I'd be interested in knowing which film you used for copy, and what specific chemicals were used for developing. I'm assuming you did the developing yourself?

          Ed

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          • #6
            CJ - Jim's thread was very interesting, Thanks

            Stephen - Can others find the service? Yes, I think so, look to a commercial photographic lab that provides the service of copying paintings for artists, there are two in my town that could easily handle it.

            Ed - What film and etc. do I use? 4x5 Pro Copy film in HC110 developer, Dilution E at 68 degrees, 5 minutes developing, with agitation of 5 seconds (using hangers pulled out of the tanks twice) every 30 seconds. Presoak 30 seconds in water prior to developement. Polarizing filters over the lens and the lights. This image was given 1 stop additional exposure as compaired to a normal image to get moe detail out of the dark areas.

            Having said that - I beleive, and it is why I have started this thread, that I can help anyone here to develop a way to acheive this result with any camera if:
            - There is access to a lens that is sharp enough
            - If using a digital camera it can create a large enough file to keep the detail that the lens captured.
            - If using film the film is fine enough grain (or a large enough negative) and you can scan the negative (it's more problematic to have a print made and then scan the print since you lose information in the making of the print and you have to hope that whoever prints it keeps the detail that you want kept.)

            The real magic to this, is not how a I do it in terms of film or equipment, but the proper use of the polarizing filters over the lights and the lens!

            I would like to walk everyone who is interested through the process of being able to do this with whatever you have!

            First you must have a lens on your camera that can hold the detail! To test this...

            1)Buy a newspaper, remove a stock exchange page, you will photograph this to test sharpness
            2)Take a picture of the page in the shade with the camera at the distance required to see an area of the page that is about 10 inches long. You must have a lens that can focus this close or a close-up filter.
            3)When you take the photo make sure the camera is rock solid - A good tripod pointing at a wall, a good copy stand or the camera set on a cinderblock which is on the ground pointing to a wall will all work.
            4)If you can vary your f stop, vary your fstop/shutter speed combinations so that you use all of your lens openings (fstops) , you will then be able to tell which lens openings your lens is the sharpest at.
            5)Use a cable release or the self time so that you do not vibrate the camera when taking your photo.

            By zooming in if digital, or with a good magnifier looking at your neg (Use the lens that took the photo if it is removable from the camera) - see if you can read the stock report info, if you can your lens is sharp enough.

            Any who wants to do this test, then post here, I will get you through the next steps. But first you must be sure you have a lens sharp enough!

            Having said this, I have not yet tried doing this with a digital camera. A friend of mine has a Canon D60 and has said he will loan it to me for testing this, I will use the same image for comparrison and post it as soon as I have a result.

            Thanks, Roger
            Last edited by roger_ele; 01-17-2003, 08:59 PM.

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            • #7
              I've had good results using an enlarging lens for copy work also. The flat field is a big plus. Talking about using hangers with 4 X 5 film brings back memories.

              Ed

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              • #8
                Just for the curious ... the lens used on our copy camera is a Rodenstock 105mm enlarging lens, sharpest lens openings f8 through f22, old speed graphic for the 4x5 camera, normal exposure for pro copy with our lights is 7 seconds at f22 (we then open the lens as needed to allow for bellows extension - bellows extension is the exposure compensation for the light lost from moving the lens further away from the film as we focus closer)

                This we probably not resemble most set-ups and that is OK, we can make anything with a sharp enough lens work.

                Roger

                Comment


                • #9
                  Ah, dip and dunk. I can smell the hypo now. Great thread! Roger how about a picture of your copy setup?

                  Bob

                  Comment


                  • #10
                    Roger,

                    You didn't wind up with my old copy setup, did you? I also had an old speed graphic. Great camera. I miss it dearly.

                    Ed

                    Comment


                    • #11
                      4x5 copy

                      Roger, are you saying to make a 4x5 copy neg then scan it on a flatbed and that will give you better quality then a paper scan?

                      Bob

                      Comment


                      • #12
                        Bob - What I am saying is that when the original has problems on a scanner because of being dark, or heavy texture, or silvering; photographing the image with a copy set-up is a good alternative. Either film or digital could be used in the copy camera. If film is used (no matter what size of film) then the negative would be scanned rather than making a print and scanning the print.

                        And yes, I will add a photo of my copy set-up, but I first want to get all who want to join in, to inovate a easy way of doing it for what they have available.

                        Ed - After thinking about your comment about the lens, I think you bring up a good point, I should at this time discuss lenses and the other stuff than affect sharpness. I would hate to have someone run my sharpness test, find their lens isn't sharp, and give up without responding in this thread.

                        If you are using a digital camera:
                        - Use the highest quality setting
                        - If available compare b&w and color settings
                        - If available try all sharpness settings

                        If you are using film:
                        - Pick a slower speed film - around 100 ISO is good - which film is not critical since you can adjust the tonal range with curves to reverse any problems that a perticular film might have.

                        If your camera has interchangable lenses:
                        -Try all lenses that you can get to focus close
                        -If the lens is a zoom try mid-zoom and all the way zoomed (optical, no the additional digital zoom).
                        -If none of your lenses are sharp and you are using a 35mm the best lens to get is the fixed length macro, usually 50mm, but sometimes they come in longer focal lengths.
                        -If you are using medium format look to the manufacturers spec's
                        -For 4x5 an enlarging lens with superior sharpness is recommended, you can expect to pay $300 - $500 new. You do have to look through the manufacturers specs to be sure which lens will be the best. Jim Conways comments about a process lens (used in the graphics field to make seperations for printing) are also accurate, but is probably more expensive than neccessary. I picked the Rodenstock Rodagon 105mm 5.6 lens. Any 4x5 works as a copy camera, it is the lens that matters, and the lens does not need to have a shutter in it.

                        Also, do use the stock market newspaper to test. higher contrast subjects or subjects without fine detail are much harder to judge for sharpness.

                        Roger

                        Comment


                        • #13
                          Test with digital camera

                          Hi, I did some tests

                          This one is shot with the Canon D60 digital camera, Polarizing filters used on the lights and the camera. Looks wonderful. Because the image is so dark we added 1 stop to the exposure. We used the only lens my friend has that can do macro, a Canon zoom (don't remember the range).
                          Attached Files

                          Comment


                          • #14
                            Test with 35mm

                            Keep in mind the the original head size of the man in this test is about the size of this happy face . These are a little out of focus here, but I don't have a high end negative scanner, so the sharpness should not be judged (these were all scanned with an Agfa T1200). This was shot with an old Pentax manual body with a 50mm macro lens. The body does not have mirror lock up so there might also be a little bounce. I will make a quick Glossy in our darkroom when I get a chance, if it is sharper I will post it here as an update.

                            The point is that considering the image size, if you have a 35mm camera you can get at the least, pretty good results.

                            After running this test, I have to admit, I was wrong. Polarizing filters are not mandatory to do copy work. I have used them for 15+ years and havn't compaired them with and without in that amount of time. When you have a photo with heavy silvering or glossy, it makes alot of difference under the copy lights, but not otherwise.

                            The attached test is made up of 2 images from Kodak PlusX b&W film developed regularly like any lab would do it and 2 images taken with Fuji NPS color film with a 80A blue color correction filter. I did this with the idea of what would be easy and available for most who do not have thier own Black & white lab.

                            Each of the films is done twice, 1 with a polarizer and 1 without. There is a ruffness to the tones without the filter, but not nearly as much as I expected with this original.

                            Will post updates as I learn anything new...

                            Roger
                            Attached Files

                            Comment


                            • #15
                              Fuji Transparency Film

                              Adding Fuji 64T Transparency film to the mix, I thought there might be a couple of advantages to using transparency film: depending on the scanner software negatives can be harder to reverse, Fuji's 64T is a Tungsten film so if you are using photofloods you are pretty close on color without a correction filter, and shooting color allows for scanning in color with those differences in the color channels being available.

                              This sample is with polarizer on the left and no polarizer on the right.

                              I left it in color in case any were curious to compare the channels.

                              In my opinion this is all information that will come in handy to get you by if you want to use what camera equipment you may already have. By far, the simplest and the best quality is from shooting it with a digital camera.

                              If anyone would like me to go further with any testing, or would like help setting up to copy, please let me know. I have some ideas for setting up a home made horizontal system that should be pretty dirt cheap and easy.

                              Thanks, Roger
                              Attached Files

                              Comment

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