BW Copy Neg vs. Scanning Test
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
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)?
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?
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.
Last edited by roger_ele; 01-17-2003 at 08:59 PM.
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.
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.
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.
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