How to convert "almost" white pixels into white pixels?

[pstein]

Assume I scanned a page from a paper-based News magazine with a Flatbedscanner.
The page contains mostly black/white and colored text and lines but also colored photos.

The scan quality is good but could be better.

As a first step I can improve it by applying some Brightness and Contrast operations.
It works but there is still some room for more improvements.

Particularly the pixels between the letters are not really white but only "almost" white.
They are some sort of light grey or light blue.

I would like to convert them to really pure bold white pixels.

So what I need is a way in Paint Shop Pro to define a threshold (e.g. color of pixel has a 2% distance to pure white) and tell PSP to convert all those pixel to white,
All other pixels should remain untouched.

How can I achieve this?

Peter

[LeviFiction]

The anti-aliasing you're talking about is what makes it look smooth.

You can use the magic wand tool set a decent tolerance that selects the pixels you want, make sure "contiguous" is turned off so it'll select all matching pixels in the entire image. Grab the fill tool and fill with White.

Or

You could try just using the fill tool without any selection, and do the same thing. Turn off contiguous, set the tolerance, and fill the whole area with white it should only fill the areas that are close enough to white.

[Andy2011]

About 18 months ago I had a slightly different problem of scanning in 70 high contrast black & white prints usuing a fairly basic printer-scanner. Some of the detail in the pictures was not showing up and I tried a lot of adjustments in PSP but with limited success.
Ultimately I got close to what I wanted by scanning each print 3 times at different settings (high, medium & low brightness) then merging the images using PSP's HDR process. The resultant 16 bit tiffs, even when reduced to jpegs and viewed on a normal definition monitor (3x8 bit), had a lot more detail.
Whilst this method may not work for your project, it may be worth trying as it gives PSP a lot more information to work with. The automatic HDR process was much better at balancing the brightness levels than my attempts.

[migf1]

An example if possible of the image to be corrected would help. Depending on the content, you may also use levels or curves to target specific tone ranges and either darken or brighten them. Maybe use masks too, or plain selections modified for smoother edges, etc.

[pstein]

The anti-aliasing you're talking about is what makes it look smooth.

You can use the magic wand tool set a decent tolerance that selects the pixels you want, make sure "contiguous" is turned off so it'll select all matching pixels in the entire image. Grab the fill tool and fill with White.

This looks good.

As I found out I have to disable "anti-aliasing" checkbox.

A related question:

What does "Feather" value mean?
I tried some values but all of them yield strange selections.
So 0 seems to be the only recommended value for my purpose.

But for which scenario is this useful?

Whats the difference to "Tolerance"?

[migf1]

...
A related question:

What does "Feather" value mean?
I tried some values but all of them yield strange selections.
So 0 seems to be the only recommended value for my purpose.

But for which scenario is this useful?

Whats the difference to "Tolerance"?

Feather causes the selection edges to gradually fade.

Tolerance determines what will be selected (how far the selection will go) depending on the current Match Mode. For example, using the Magic Wand with Match Mode set to Color and Tolerance to 0, will select only those pixels that have the exact same color (hue & saturation) with the pixel you initially clicked on. If you increase the tolerance, pixels with a similar color to the initially clicked pixel will also get selected.

There is not a single rule of thumb really, since it depends on the quality of the image (size, resolution, color-depth, etc) and the effect you are going for.