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View Full Version : Slides (some prints) appear darker or blurry when scanned.


tbookout82
11-24-2003, 12:07 AM
I am using an HP Scanjet 3570c and associated software to scan and post slides and prints. Often they appear darker when scanned than they really are when seen as prints or slides with projector. Another problem I've been having is that they will have soft focus or be downright blurry. I have had many rejected for this reason lately. The slides and prints themselves are in good focus and generally the lighting is good or decent. Some shadows tend to be a little darker on the Kodachome 64 slides due to the nature of that film. When I try to correct the brightness or focus I get scan lines and a generally bad quality scan. What might be causing these problems. Is there a way to fix them? Any Suggestions? Thanks in advance!

E.M. Bell
11-24-2003, 03:27 AM
From looking at the rejects, the first thing I will suggest is to scan them at a higher res... With slides I usually scan at least 800 to 1200 DPI, sometimes even higher. This will give you a much bigger base image to work with in your editor. Once you have it scanned, do your cropping, rotating and such, and then size your image, with the res set to 72 dpi in the final. (the highest display quality for just about all monitors is 72 dpi, so saving the image any higher will just make for a bigger file)

Once all of that is done, inspect the image for any sign of "scan lines" or visable pixels (grain)... If lines are present, you can usualy soften them by adjusting the contrast a tad, but this will only work on very minimal lines, and will usualy darken the image. As a general rule, you will find that these scan lines and such will show up in the low contrast areas of the image..ie...darker areas. Once all of that is done, you can play with the image to lighten or darken as needed, adjust the colors, and use of the sharpen feature will help the soft focus problem....if the editor has those features. All of this depends on just how good the slide is...with a poor light situation, there is only so much that can be done! (One hint..for those shots that have low contrast, questionable light ect, try converting to a greyscale (B&W)...sometimes that is a good way to salvage a image, it wont always work, but its worth it when it does)


One other suggestion...give higher speed film a try...K64 was the "gold standard" of RR photography for many years, but in the past few years, Fuji has introduced higher speed slide film that is really giving Kodak a run for the money. I know of several die hard K64 users that have converted to Fuji.....give Velvia or Provia a try...

I am sure other folks can suggest other things, and compare the virtures of Kodak versus Fuji ..I would be interested to hear those comments myself.... Hope this helps...

oltmannd
11-25-2003, 03:48 PM
I have EXACTLY the same problem you are encountering. The problem is that flatbed scanners generally do a lousy job with transparencies. It doesn't matter if I scan at 1200, 2400 or 4800 res (my scanner is 2400x4800 optical res.), I still get scan lines and noise of the same magnitude.

The film doesn't matter, either. I have shot every type of Ektachrome (Elitechome to you young'uns!) and Kodachrome (ASA 25, 64, 80, 100, 200) and have the same trouble will all types.

Every scan needs sharpening, but with the noise in the scan, you wind up sharpening the noise and much as the subject.

I have had some luck adjusting the black and white points, but if the slide is a 1/2 stop underexposed, the scan usually turns out mediocre no matter what. Slides that are slightly overexposed seem to turn out better. (But the slightly underexposed are the ones that look best projected!)

Using Adobe Photoshop, you can get rid of some of the scan line/noise by using the "reduce graininess" feature and then do some heavy "unsharp masking".

You can also try sharpening/softening areas of the scan selectively to avoid areas with the noise/scan lines.

I think the real solution is to get a dedicated film scanner, but they are still too rich for my budget.

Here's a good web site about scanning: http://www.scantips.com/index.html

-Don

tbookout82
11-25-2003, 09:57 PM
Thanks Emmett and Don. I will try some of the suggestions when I get a chance and see if they help. I look forward to hearing from anyone else out there with suggestions as well. I'll let you know how it goes. I may just have to break down and get a better digital camera for shots I plan to upload. I have had good results with Wal-Mart's scans of print negatives, but recently switched to slides at the prompting of a friend. I really like the slides except that I have not had good results with scans of them even though I have a TMA built in to my scanner. I have tried Kodak E-100 and EliteChome 100 and 200 as well as K-64. I like the K-64 results on sunny days and some other conditions have been decent. I like the ekta/elite chomes for general shooting and cloudy days, as well as various print films (both Kodak and Fuji). I have not tried Fuji slide film yet, but probably will at some point. Thanks again guys.

tbookout82
11-25-2003, 09:57 PM
Thanks Emmett and Don. I will try some of the suggestions when I get a chance and see if they help. I look forward to hearing from anyone else out there with suggestions as well. I'll let you know how it goes. I may just have to break down and get a better digital camera for shots I plan to upload. I have had good results with Wal-Mart's scans of print negatives, but recently switched to slides at the prompting of a friend. I really like the slides except that I have not had good results with scans of them even though I have a TMA built in to my scanner. I have tried Kodak E-100 and EliteChome 100 and 200 as well as K-64. I like the K-64 results on sunny days and some other conditions have been decent. I like the ekta/elite chomes for general shooting and cloudy days, as well as various print films (both Kodak and Fuji). I have not tried Fuji slide film yet, but probably will at some point. Thanks again guys.