Scanning paper photos on a flatbed scanner- hints for a technical virgin?

Biggles

My cup runneth amok.
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I tried scanning silver prints for the first time today. Surprisingly, my sharp prints look like crap on-screen. Muddy, with some slurring of fine details like human hairs clearly visible in the paper prints.

Here are my sizes and settings:

*4" x 6" (100 x 150mm) print, black & white

*scanned full-size, at both 300 and 900 DPI resolution, in the scanner's "true color" mode

*saved and viewed as .tif


Pictures from member galleries here generally look far cleaner and sharper by comparison, on the same screen . However, I have no idea if most people here scan negatives or prints, or if it makes a difference.

Am I doing something blatantly wrong, or are scanners not created equal? (The one I used is a Hewlett-Packard. No, I can't post the pictures yet- no way to get them out of the other computer until I can borrow a USB memory stick.)

Any insights will be appreciated.
 
For scanning prints and hardcopy things (and once a negative, actually) I use a HP 5300 here at work. I do it often times with default resolution, but sometimes setting it as high as 1200.

I always be sure the glass is clean.

Then touch up the levels and such in Photoshop.

I've actually had good luck making 20 year old color prints look much better.

The "Leaving on a jet plane" and "Northwest and Southwest" in my gallery were plain old Wally World 4x6 prints scanned on this thing with some minor tweaking after.
 
Some hints i can give (almost all my images are scanned as prints on a flatbed, about same size prints as yours):
-scan in 16-bit if scanner allows; touch up the 'levels' in PS in 16-bit mode. Use the slider triangles in "levels" for the shadow and highlights - for a scene with both dark and very bright tones, "auto" might work just well. Finally, use the midtone slider triangle to set the general tone.
-use "curves" if you want to change certain tones only, to brighter or darker. Fix a few points on the curve and tweak only the region which you want to enhance.
-don't use strong sharpening at scanning (the scanner software should have somewhere a setting for the sharpening level). None or low sharpening should be enough; do the rest of sharpening as USM (unsharp mask) in photoshop. For 300dpi scan of 10x15 prints, a radius of about 2 and a USM level of about 70-100 should work okay; if it's not enough, apply a second USM with same or smaller radius and a level of 30-40. Use treshold not higher of 4-5 if needed (should affect grain if there is any. like delta3200 films produce visible grain in this size photos; or in very dark areas the scanner might produce noise which also can be enhanced by USM if you use no treshold.)

For images with a short tonal range (i.e. no deep black and/or no bright highlights), DON"T use the "auto levels". Use the manual level setting and common sense. "Auto" wants in every image a bit of max highlight and a bit of deepest shadows so he will set the histogram in such way.

DOn't forget - use the 16-bit image as long as you can. USM, levels, curves are allowed on 16-bit level in photoshop 7. Cropping is not.

Also what dmr wrote - be sure the scanner glass is clean. Also from the inside - plastic components can outgas and fog the inside of the scanner glass, which can be cleaned.
 
Q: at 300dpi with the length set at 7 inch, my scanned file comes to about 845kb. This is too large to upload to the gallery. How do I compress the file without the photo becoming really "noisy"?
 
300dpi, 7inch means 2100 pixels on screen... You don't need 2100 pixels for uploading here; 700-800 is enough.
Reducing it to 700 you reduce file size tremendously. Use "resample" and set the image size to 7-800 *pixels* as the largest dimension for the rectangle. Use a jpg compression of about 70-80 and image should be within the 150kbyte limit but still good quality.
 
Are you scanning for the web only? It is important to some degree on how to set the scanner. Most recommend a setting of no more than 150dpi for posting to websites, some as low as 72. And since you need only 700-800 pixels on the long side for this site, you will be forced to change the scan post operation. I have had success for posting to websites by scanning at 125 with the target size of 1000pixels on the long side with the USM set at low or medium and liked the results. I use an Epson 3170.
 
Pherdinand said:
For images with a short tonal range (i.e. no deep black and/or no bright highlights), DON"T use the "auto levels". Use the manual level setting and common sense. "Auto" wants in every image a bit of max highlight and a bit of deepest shadows so he will set the histogram in such way.



A small addition: Sometimes you can brighten up yor prints even more if you close levels after you have set them manually, open them a second time (You'see a histogram that looks like a weird comb) and hit auto-levels. This works on digital files as well.
 
Biggles said:
Thank you all for your comments so far.

Is it normal to have to digitally sharpen a scanned photograph so its on-screen crispness approximates what I see on paper?

Even if you shoot digitally and don't do in-camera sharpening, i.e. shoot raw, you'll have to sharpen in PS.
BTW, Photoshop Elements has a "save for the web" option, which works fine, provided you have slightly oversharpened your photo in the first place.
 
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That's true, Jaap, but only if you do "levels" in 8-bit mode. I would suggest to always do it in 16-bit mode, and transform the image to 8-bit only at the end, avoiding this way extrapolation of the histogram or steplike (comb-like but without a "base") result, which manifests as missing tones on the image.
 
Sure, I usually do 16 bits as well, but we are talking photo's that really need correcting here.
And- if you use 16-bits PS and TIFF in PS as you should, you need at least 2 Gb RAM, especially if you scan at high resolution (= 100-150 Mb files) ,which I have upgraded to for exactly that reason.
 
I think PS Elements 2.0 will not use 16 bit files which is one of it's drawbacks that the newer versions might have fixed.

Bob
 
"Are you scanning for the web only?"

Yes. Strictly to post finished prints on discussion fora like this one- nothing more finecore than that.

"Flatbed scanners always give results that are a bit soft compared to the original print."

Damn, I'm glad I asked. I'd really had no idea. Going to try some sharpening options. (I have Photoshop LE.)


Again, I thank you all. What a great bunch.
 
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