How do I change a "mottled" background?

[Roger at CCCC]

I have just downloaded Photofilter 6.2.3 and would like to try to use it to perform a simple task, but I can't get the program to do anything at all.

What I want to do is change the background of a JPG image file. The image is simply black text on a "mottled" gray background. By "mottled" I mean that the background is not one color but a range of different gray colors. I want to change the background to white, so that the JPG image file is simply black text on a white background.

I am guessing that the "Adjust Color Range" option might do this. However, when I click on this option, "Color 1" is blue, which is not in my image. Furthermore, Preview doesn't seem to do anything. "Color 2" is a slider, but it's not clear where white is on the slider scale. When I click on the "?" help option, there does not seem to be any information at all about the "Adjust Color Range" option, if indeed this is the correct option to use.

I would appreciate any instructions or suggestions that anyone might have. Since I am new to this program, I would appreciate detailed step-by-step directions, if in fact my task can be accomplished.

Thank you very much in advance for any suggestions.

[Tom]

Hi Roger,
I think you should use the magic wand to select the black color of the text.
Then, when the text is selected, right clic and inverse the selection.
So the whole background is selected without text.
Menu Filter /Colour/Colored layer white Opacity 100.

[Roger at CCCC]

Thank you, Tom, your instructions were exactly right. My only remaining problem is that after I finish your instructions, the image is apparently in some sort of "edit" mode where the border is "crawling" and the selected (inverted) text is "pulsating." If I save the image, it is in fact modified in the saved version, but is there is a way to make the changes take effect on the screen without having to save it, and then reload it? Thanks again - I really appreciate your help and it would have taken me hours to find the right option.

[Tom]

It seems you describre the selection which remains.
In the help file (Menu ? / Information ) of PF, some shortcuts are displayed like Escape key, which generaly cancels any action in process, and also hides the active selection.
A square dotted button matches the same effect.
Or in the Selection Menu : Hide selection.

[Roger at CCCC]

Thanks again, Tom, for your last comment. For some reason I didn't get email notification of it. In any case, pressing Escape at the end of a selection and modification was what I needed to know.

Thanks again.