Document Colors

[Wor.Geordie1]

Hi,

I am using Windows 10 Pro 64 bit and an Epson V550 scanner.

I've just scanned an old exam paper for one of my students, using the Epson interface, and I'm trying to change its colours to black background with white text.

Regardless of which options I choose under Preferences, nothing changes.  I've tried 'Use Document Colors' and also the accessibility options and tried numerous combinations but neither the background or foreground colour changes.

Also, when I emailed the exam paper to the student, when she tried to print it, she got black background with white text which used an huge amount of ink.

Is there some setting either in Adobe Reader or within the scanner interface that I need to change?

Thanks,

[Document Geek]

Nothing is changing becasue it's a scan. The "Replace Document Colors" in the Accessibility preferences only works for PDFs that were created digitally (not from a scan). The only way to change the colors of a scanned PDF is to open it in Photoshop and invert the colors there.

As for why your the paper printed with a black background, maybe that's because of the settings used in the Epson interface (which I can't help you with).

Why do you want to see it on your screen with a balck background?

[Wor.Geordie1]

Hi,

Thanks for your prompt reply.

The reason I prefer a black background and white text is due to my visual impairment.  Documents (or anything else) with a bright background are really difficult for me to read.  I will try making the change in Photoshop.  Do you know if that will affect the way it prints?

Thanks,

[jgke]

Hi there,

To change document colors on a scanned (I assume typed) document, first run "Recognize Text" under scan and OCR. This will convert any scanned text into readable text. Be warned that depending on the qulity of your scan, this can have mixed results. Afterwards, replacing document colors should wrok realtively well.

If the background is still white or there are white boxes remaining, the OCR has detected thee white background as an "image" and you will have to delete these under "Edit PDF". Likewise, the text may have been OCR recognized as the wrong color, in which case you might have to manually select the detected text and change it wo whatever color you are looking for.

Hope this helps.

[Luke Jennings3]

Your suggestion is a good one. If you combine it with a preflight profile to move all images to a layer, then delete that named layer (two custom preflights combined into an action), it might work well. Another option that might work with the original scanned image is to run two custom preflights, one to map all whites to rich black* and another to map all blacks to white (also combined into an action). *the choice of rich black should protect the new color from the subsequent black to white mapping.

The attached screen shot shows a preflight profile mapping a blue color to black.

[Luke Jennings3 · Accepted solution]

You can use the accessibility tool in Windows 10 to invert your screen colors:

https://www.youtube.com/watch?v=PbFCv_5QiCg

On a Mac you can go to System Preferences> Accessibility> Display> Invert Colors.

The student may have accidently selected an invert option when printing? send the PDF to someone else and ask them to make a test print for you. Also, tell them to print from Reader or Acrobat.

Inverting the scan image in Photoshop (Image> Adjustments> Invert) will definitely cause it to print inverted.

FYI, you can make a PDF that will view inverted and print normal in Acrobat or Reader:

Create an InDesign page with two layers, call them normal and inverted (place a separate PDF into each layer, the inverted layer PDF inverted in Photoshop), export as a multi-layer PDF. In Acrobat, adjust the normal layer properties to Print but never view, adjust the inverted layer property to View but never Print.

[Wor.Geordie1]

Hi Luke,



Thanks for your reply.



I do have the high contrast options on in Windows but this causes all sorts
of problems with other things. Also, despite having the Windows colours set
to white text on black, Adobe just ignores this even if you tell it to use
Windows colours.



I'm not familiar with the packages you mention but I have access to them so
I'll follow what you said.



I'm amazed how difficult it is to change the colours of a scanned document,
I thought you would be able to just tell Adobe Reader to invert the colours
and it would - I've a lot to learn.



Thanks again,





Brian









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[Luke Jennings3]

Hi Brian,

I'm using a Mac, when I change the system preference to invert the display, everything on my screen inverts, including PDFs viewed in Reader & Acrobat. The link to the Youtube video shows a keyboard shortcut to invert the screen colors on Windows 10, the white text on black is probably a different setting, which would not apply to your scan, (which is an image), just to be clear.