Thanks for that screenshot, matteone. It shows that the resolution of the front-facing camera may be the limiting factor.

To improve the quality of the image, perhaps the application can be modified to use the main camera. Of course the difficulty with that approach is that you can't see the screen while you're pointing the main camera at your face. But if you have a small mirror with you, you can position it so that you can see the N900 screen.

Regards,
Roger