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BRUCE EATON
19-Jun-2005, 20:41
Took my first large format photos the other day! Shot four images of furniture I've made with the hope that I will be able to use images for my portfolio and website. I used Kodak portra 100T with incandescent lights (2 at 250W), 210mm rodenstock lens and my finally completed bender camera, backdrop was a light silver/grey seamless paper. Exposure was 10-15 seconds at F45. Contact proofs look okay for my first attempt. I purchased an Epson 4990 scanner so I could load up the images and use them in my website, make postcards etc. My scanned negatives are much darker and with more of a blue/grey color than the contact printed photos. When I scan the contact sheet, they also get slightly darker and maybe a bit more blue, but not nearly as much. Wondering what might be causing the scans to darken so much. I've never used photoshop elements before and have managed to get the photos to look okay from the scnned negatives, but they are more contrasty with loss of detail in the shadows (i.e. on the rear chair stetcher, I can see the maple curl in the contact print, but not in the scanned images). Could the problem be my exposure? Any advise would be appreciated.

Kirk Gittings
20-Jun-2005, 08:02
These scanners do color negatives extremely well. I do 20 to 50 a week with one. Which scanning software are you using? If you have Silverfast learn to use it. The most common problem with scanning negatives is to make absolutely sure that the scan frame is within the image with no film edge or film holder included. Otherwise it will throw off the values dramatically.

Leonard Evens
20-Jun-2005, 08:17
You have to think of your color negative as a starting point from which you can, with skill, produce a reasonable rendering of the scene. All scanning software allows you to adjust the range of values included in the scan, the contrast for middle values, and the color balance. Some allow you to make sophisticated changes in the separate colors R, G, and B. In any case, you can do that and more in a photoeditor such as Photoshop or the Gimp. If you were printing conventionally from your negatives you would have to determine exposure time and fiddle with color filters to adjust the color balance, so the same issues would arise, but you wouldn't have as much control unless you used cumbersome advanced techniques by use of masks and similar methods.

Your scanning software will of course make the best guess it can from readings it sees. But that is only a rough guess and is seldom right. You should study some of the texts explaining how to use Photoshop to modify images. Real Wolrd Photoshop is one such text, but there are many others. I like Dan Marguilis's Professional Photoshop, although it is oriented primarily towards prepress work using CMYK. With a little imagination you can apply the same principles to RGB. He makes the important point that you can seldom get all the colors in the scene right. What you have to aim for is a plausible rendering of the scene which concentrates on the important colors.

Including a neutral gray card in one or more exposures with the same lighting can be helpful.

Ted Harris
20-Jun-2005, 08:28
Bruce,

Not sure where to start since there are soooo many things to consider but here goes:

1) For the most accurate color rendition you are always better off starting with the original image. Having said that T (for tungsten) films are not balanced for use with regular incandescent bulbs but rather for photofloods that give a constant light output at, usually 3400 degrees K). Regular incandescent bulbs may come close but not always. You can easily buy 3400K bulbs other than that it is hard work to make the corrections. If you are going to be doing a lot of this work a small investment in some lighting equipment designed for this sort of work will pay off and will greatly ease the rest of the process, both in terms of your time and the final quality. Also, even if you can’t do any more than you are now with lights you need to experiment with their placement and other exposure combinations. Properly placed lights, even at 250W each, should allow you to expose at a much faster shutter speed. You are also not likely to be gaining anything much at f45 over an exposure at f22 and may even be losing some resolution (of ocurse yo may want it for the depth of field).

2) At exposures of 10-15 seconds you are in the zone where reciprocity failure begins to set in with this film and you need to adjust your exposures accordingly. Failure to do so affects exposure. Additionally, some color films are balanced in such a way that slow shutter speeds cause a shift toward the blue/blue green end of the spectrum. For example, Polaroid T59 has a markedly blue-green cast at speeds slower than 1/125, at 1 second it is very pronounced.

3) There are many variables in the scanning process (see my article in the current issue of View Camera magazine for more details) but you should be able to get better results. First you need to be sure you calibrated your scanner using the instructions and software that came with it. Second, the 4990, while an ‘entry level’ scanner, is still capable of giving quite acceptable results, especially for your purposes but you need to master the software. You are far less likely to get good scans using the auto settings than you are if you make custom adjustments. Most importantly, manually set both the white and black point and then check the curves to insure you are getting the brightness and contrast you want ..... you do this before you scan. These steps become particularly critical with negatives such as yours, which I suspect may have somewhat difficult shadow areas.

4) I am not familiar with Elements and have never used it. The following comments relate to the full version of Photoshop but I believe also apply to Elements. Once you have completed your scan you can further adjust the image in many ways. A properly exposed negative will require little adjustment beyond sharpening. If you do need to adjust color values you can do so with the color controls you find at Image>Adjustments>Hue Saturation.

That is a quick response ..... I suggest you do a bit of basic reading. Tow books I recommend are “Real World Scanning” and “Photoshop for Photographers.” Again, I want to stress that working on better lighting may be the easiest and best cure.

Kirk Gittings
20-Jun-2005, 09:41
I don't think the issue was with lighting and film choise.

"I used Kodak portra 100T with incandescent lights (2 at 250W)."

"Having said that T (for tungsten) films are not balanced for use with regular incandescent bulbs but rather for photofloods that give a constant light output at, usually 3400 degrees K). Regular incandescent bulbs may come close but not always."

This is really not an issue with color negatve films as architectural photographers can attest. We use contemporary color negative films all the time in completely outlandish lighting situations. The film is so forgiving that you can correct it back. I have used daylight color negative films for twenty years under incandescents with no filters and no problems. Even printing C prints was no problem and scanning them is like butter. My cover of Texas Architect this month and New Mexico Magazine two months ago and some of the images in the articles were done exactly this way, daylight color negatives with household halogens (2650K). I do it all the time for these and national magazines. I learned it from Joel Merowitz over twenty years ago.

Something else is at play here.

Henry Ambrose
20-Jun-2005, 20:23
Bruce,
Remember the first chair you ever made? Its probably not nearly as good as the ones you are making now. Just as in furniture making there's a learning curve to scanning and it sounds like you are just getting started on the road.

If you are using the Epson software I suggest you follow Kirk's advice about being sure to not include any part of the film not in the exposed area. Then by clicking on "auto" you should get a reasonably decent scan. You can even select a small area and move it around the image area to get different "auto" results, then pull the selection out to the full frame and click scan. You ought to get something pretty good following this most basic method. You can add more manual adjustments in your scanner software by clicking on "professional" (or whatever its called up there in the right hand corner I think) to get to the higher level controls. Then you can tweak to your heart's content. Play with it, it won't break.

The other big issue concerns color management for your monitor, computer and printer system. You really should buy a calibration package and use it to get your monitor, your files and your printer to agree on color -- then what you see on the screen will agree more closely with what you see on the print. If you have not done this you may have a very difficult time ever getting good color.

And a good Photoshop book would be money well spent.

If you get stuck I'll be happy to scan one of your negatives to see if the problem is in your film.

BRUCE EATON
21-Jun-2005, 16:18
Thanks for your help. I tried a couple of your suggestions and the results were much better! I'll do some more reading, too...