there are many scanners which couldn’t catch colors at the sufficient level even adjusted by hands, or softwares. even though the latest models, it can’t be perfect. for example, Canoscan5600f which I used before is the latest canon model, but it’s very reddish and can’t be good without tonecurve adjustment. old 8bit scanners must be worse than 5600f. it8 target possibly ease the hell scanner’s color, but it’s far from good (sometime, become more worse)

merun, could you show me a raw (without any color profile, or adjustment) scan of the cover of Planetarium?
using my e-mail, or post it with “test, hold” tags on moe.imouto.
because I have the same book, I can compare the color distortion of yours with mine, then can judge it’s fixable or not. (￣▽￣)ノ

ps; Epson perfection V600 which I’m using now has the most accurate colors as I know. it’s my first recommendation for a new scanner.

Lol, I don’t lose my posters, I put them in a very large file so that they get flattened and are safe.

For final image, yes 8bit is not an issue. 99% of screen can only display 8bits, or even less. The problem on my scans is that it clearly lacks some information on the red channel. I checked if the light of the scanner didn’t alter the color, but it didn’t seems to. The icon. 02 cover has weird color; her skin looks yellow, while it’s supposed to be a little bit more redish.

Now it’s only in theory, but higher color depth should be able to catch all these informations that my current scanner missed. Also, for post processing like leveling, I can work on the level without clipping colors on the final 8bit images. Of course, there are other things to take into account for color accuracy, like calibrating the whole acquisition chain, including scanner, screen.

I’ve never removed a poster from an art book, it’d be the same as tearing a page out to me >_< Magazines are a different story, but since I kept losing them after removing the posters, I've stopped with that too ^^;

Also, the 8 bit thing isn't the issue. Just about every image you've ever saved online is in 8-bit. Just open any image you've downloaded in Photoshop (even PNG), look at the grey bar with the file name + type on the top of the image and read the end; it'll say (RGB/8). If you were to do your images as 16-bit, you'd have to output and save them as TIFF, PNG, PSD, PDF etc and they would be around 100MB each for 600DPI. So… is that really the way you want to go? XD