How to photograph a document and make it look like a b&w photocopy

June 25, 2009 5:39 AM

I would like to photograph a fairly large number of archival documents and old books, and then make them look like a regular black and white photocopy.

I have Photoshop, but am having a hard time applying the right filters, etc. Any advice on how to accomplish this efficiently and effectively? (I know this would be much easier done with a scanner, but the documents are fragile so this is not possible).

posted by agent99 to computers & internet (7 comments total)

Not sure which version of PS you're using, but the Photocopy feature would probably work. It's under Filters, on my version Filters->Sketch->Photocopy.
posted by Rykey at 5:57 AM on June 25

Just as a starting point: Bring up the Levels tool, and use the white point eyedropper to select the background paper. That should get rid of the yellow cast. You can then use the black point eyedropper to select the text color as black. You'll have to zoom in, and if there are variations in the text color, choose the lightest "black". You can tweak it further by using the sliders. Then, convert to grayscale or bitmap to remove color.
posted by The Deej at 6:02 AM on June 25

Is it that you want it to look like an actual photocopy? Or you want it to look like a stereotypical, high-contrast, copy-of-a-copy-of-a-copy photocopy? I ask because, contemporary photocopiers churn-out some fairly high-quality grayscale images.

If the latter, can I assume you've played with the Photocopy filter in Photoshop and not found it satisfactory?
posted by Thorzdad at 6:03 AM on June 25

Try switching it to Grayscale and then to Bitmap. Choose the Halftone Screen method and experiment with the various settings to find something that you like. This might be more low-fi than you want, but I'm sure you can experiment with layers and blending to find an appropriate effect.

Then record it as an action, and either export it as a droplet or run Automate - Batch.
posted by Magnakai at 6:14 AM on June 25

"Threshhold" lets you set a midpoint, where everything above is considered white and everything below is considered black. This will give you a crisp, sharp text that will be good for OCR and look great when printed, but look more like a fax on the screen, and very rough images will not do well; Photoshop has dither filters that will give a similar quality but more tolerant of grays. If you just want it to look grayish, set your camera to photograph in black and white, or change your image to Grayscale in Photoshop, and use Levels to adjust the image to something readable. Threshholding and then saving as a compressed TIF will give you the smallest filesize, but Grayscale will probably be the best screen-readable version for the filesize. At my job we're doing something similar with books - we photograph in gray, increase the contrast and dither it to 1-bit, then do a dilation to clean up speckles, and then resize it a little smaller. It's speckly, but it takes an 11x17 image down from 10MB to 600K, and is very readable despite the old india ink handwriting.
posted by AzraelBrown at 7:12 AM on June 25

I find that pictures of archival documents or books are a lot more readable once they have been sharpened. How much you should sharpen them, and how, depends on your personal preferences.
posted by mattn at 7:55 AM on June 25

This guy made a great book scanner. I think his post on Make goes into image editing as well.
posted by orme at 8:58 AM on June 25