Retrieval of origial text

[p.cialfi]

Here is a challenge for Photoshop users.

A handwritten text was written in blue biro, then scribbled over with black biro.

The challenge is to retrieve the blue writing.

The original document is retained.

Several methods have been tried, but as yet without a good result.

Hi-resolution scanning directly only scans the black on top of the blue.

However, in theory, if the page is scanned from the back, i.e. through the paper, then the scan should have blue on top of black, and the image can be mirrored.

So far, it has not been possible to adjust the brightness and contrast to be able to read the blue ink.

Also, an attempt to subtract the black, and only the black, was only partially successful when trying the Select-Colour Range option.

If anyone has a tried-and-tested solution, it would be much appreciated.

patrizia cialfi       [Personal info removed by mod]

[jane-e]

If the image is on one layer, then the pixels have been replaced and are no longer there. You will not be able to retrieve the blue writing that was redacted.

~ Jane

[Per Berntsen]

You could try scanning the paper as film, which requires a flatbed scanner with a transparency unit.

The Epson 800/850 and 700/750 scanners as well as the older 4990 can scan transparencies up to 8 x 10 inches.

Another option is to put the paper on a lightbox and photograph it.

Depending on the thickness of the paper and the intensity of the light source, one of these methods might work.