Advice on creating high-quality scans

[tsuk]

Hi, everyone,

A friend of mine has given me a stack of old sheet music, none of which is currently on IMSLP. Some of the items are on wishlists, for example two of Hans Huber's piano trios. I'd like to scan and upload them, and I want to do a good job.

For my scanning needs, I've been using the iOS app, Genius Scan, which works pretty well in general. But it's having trouble with this music, for a couple of reasons. First, it doesn't lay flat, and when I use a piece of plexiglass to help, I have issues with reflections. But more importantly, the algorithm Genius Scan uses to turn photos into black & white PDFs doesn't put the threshold in the right place when confronted with paper yellowed with age.

So I'm looking for advice here, hopefully advice that doesn't end up costing me a lot of money.

Thanks!

[coulonnus]

In which format are your images before you convert them to pdf?

Read https://imslp.org/wiki/IMSLP_talk:Scanning_music_scores

[tsuk]

Thanks for the reply, coulonnus!

I don't convert them to PDF: that's what Genius Scan outputs. If you scan only a single page, you have the option of JPEG.

Maybe what I need to do is find an app that does some of what Genius Scan does (particularly easy correction for camera angle) but can output TIFF files.

Thanks!

[coulonnus]

Then convert the .jpg to .tif with a well chosen threshold and forget Genius Scan.

Are you using a camera or a scanner?

[tsuk]

I'm using an iPhone: I don't have a scanner, and would prefer not to get one.

[coulonnus]

Then does it provide 1-page .jpg images? If these images are not perfectly rectangular because of the photograph angle I have a procedure to improve this. What is the image size?

Note that the Huber Trio Op.20 has been added!