Can someone recommend me a handheld scanner for textbooks?

[PixLab]

(05-04-2022, 06:40 PM)Chemist116 Wrote: Regarding your suggestion about Amazon, I've been doing exactly that for other products but since I am not very familiar with scanners I just wanted to ask people who have used these the most.

I didn't know about that complain about the problem which arises due the edge of the wand type scanner. In the previews and examples shown it appears to be that it is slim enough to sweep covering a little bit of larger portion of the middle as when you rub through the surface you can travel tangentially to the rounded corner. For that specific reason I thought that such distortion could be minimized but it appears not. So thanks for that advise.

Yes. I've seen those open book stands before. In fact there is a DIY instructable here which comes with directions on how to take pictures of the book and use it as a scanner.

I took a closer look at your example and this shows a little bit my concern. How to reduce that "rounded distortion" near the middle. It appears to be that when you use the black and white filter this is aggravated. Perhaps that if you use that wedge style book stand and take a picture parallel to one page it might produce a better result?.

I'm not familiar either, but that's the way I think I'll do it

This DIY is good, I would follow it. The most important is the light, a well lit page with a constant light = a  better, easier and faster post processing
The cheap/desktop light one on this image is good enough with a good bulb, or use some LED


You can put a thin white paper in front of the light or a frosted plastic book cover, you know the thing for the school, it will diffuse the light to not have a brighter spot on the page if ever you got a bright spot.

(05-04-2022, 06:40 PM)Chemist116 Wrote: At this point, I can tell you that I might want to try the camera thing to see the result. Which app do you think will yield the better results for this?

Give it a try, after you  like it or not, but at least you tried  
I don't have any particular app, I would just take pictures, then transfer all images to my computer and use GIMP ➤ with the use of the G'MIC plugin first (for example for the contrast) as it can process a thousand layers at once, thus giving you time to drink a nice earl grey tea while processing  

The other advantage of layers is the GIMP's crop and rotate tool, if your phone/camera is on a very stable tripod/place, or on a pile of DVD/BR/Books and you don't move the book as you do/scan/take picture of all the same side of the book's page first, you just have to crop/rotate at once in GIMP

(05-04-2022, 06:40 PM)Chemist116 Wrote:

Ofnuts Wrote:Actually a bad idea. You can definitely increase contrast to make the page background white, perhaps after equalizing the lighting over it, and the characters black. But a pure threshold is going to make pixellated edges and specks all over.

Btw, this is what you get with at scanner app on an Android phone (Xiaomi Note7). Metal ruler included so you can ascertain how small some characters are (like the exponent "θ").

Well that speaks for itself. What app did you used for getting that image?. Actually the ruler kind of blocks certain characters and might be what I want to avoid.

At this point I think in terms of quality for this is. How can I reduce the background color so it is presented as "pure" white so when it is later reprinted doesn't cause some unwanted noise?.

Is there a smart filter in Gimp for that or something that you guys know?

I gave you the Threshold tool because you asked if GIMP has it, but know that @Ofnuts is absolutely right, and yes there are "filters" like the curves, levels, brightness contrast and many-many more options and ways, all natural GIMP' tools or with G'MIC to apply in many layers at once in GIMP

In the end, have a stable tripod, don't move the camera, don't move the light, don't move the book, just turn the pages, take picture of all the page on the same side, next, next, next, and you would be able to "mass" process in GIMP
Then do the same on the other side of the book, then use the magical Interleave layers from Ofnuts to regroup the pages in proper order. Yes all that in GIMP