Image quality requirements

To obtain a reliable prognosis, please make sure that

1. You have a front and a back image of your object (scans are preferred).
2. Your image format is: tif, png, ppm, bmp or jpg.
3. The minimum image resolution is 300 dpi.
4. Image distortion is minimal.
5. Scaling of front and back image should be similar (again: scans are preferred).
6. Artifact alignment angle for front and back should not differ.
7. The background contrasts with both ink and paper (rather use no black or white)
8. The background has no structure (no textile etc.)