White text on black

[paieye]

I have got a file that is in TIFF and also in PDF. Whether I use Preview for the former, or Skim for the latter, the display is white text on black ? How can I correct this please ?

 

[dwig]

One, why do you think it is wrong and needs "correctlon"? It may very well be the way the file's creator wanted it.

Two, altering the TIFF to what you like is a simple matter in most image editors (e.g. Photoshop, ...). Exactly how, and exactly what the needed tool or function needed, will vary between apps. In Preview, you would select "Adjust Color" from the "Tools" menu and then drag the left most and right most handle, one at a time, under the Histogram and swap their posiitions.

Three, altering the PDF can be tricky. it all depends on exactly what lives in the deep dark internal structures in the PDF. Without knowing what tool was used to build the original file and then to generate the PDF it would be a total guess and any such guess is most likely wrong.

 

[kohlson]

Does the pdf render as you are expecting in Adobe Reader and not Preview?

 

[paieye]

I worked happily for hours in Preview on the TIFF with the text in black and the background in white before the colours were suddenly reversed. I shall try these suggestions and report back.

 

[paieye]

I worked happily for hours in Preview on the TIFF with the text in black and the background in white before the colours were suddenly reversed. I shall try these suggestions and report back.

I am completely unable to find out how the colours came to be inverted or how to uninvert them. However, I have achieved the result in practical terms by clicking File, Revert To, Browse All Versions. This displays a sheaf of versions rather as Time Machine does. I then clicked the arrows over at the right-hand side of the window until I found a black-text-on-white-background version. I took the precaution of exporting it under a completely different name, and all is now well. My thank to those that have tried to help.