How to clean background color of photo or scan image?

[k2mountain]

I took a photo of drawing on a letter paper.
The image file was saved in JPG format (900KB).
When I opened with the digital camera bundle program and Painter, it shows light gray color.

Secondly, why the painter (X) shows almost 20 times bigger Canvas size?
The JPG file is 900K. Painter displays it 20M format.

I changed the size of Canvas and resolution to make it small.

[Arshes Nei]

I think Painter is trying to look at the image as .rif format, not jpg from what it sounds like. It may be a color setting issue too but I never get pure white when scanning or taking a photo. "White" is relative ;)

Use Brightness Contrast to adjust the image and don't try erasing out the grey.

[Rich_C]

Yeah dont worry how it looks to start with, change the brightness and contrast to make it look how it does on the paper - it's just what scanners do as far as I can tell.