Thanks for your comment. I thought about the monitor quality as well, but being two different pictures shown on the same monitor if there was no difference they should look the same. I have applied an Octree algorithm in order to see if I could highlight the differences. As you can see the picture now shows a difference in terms of "lines" height. On the left they are wider than on the right. In normal view the lines on the left can be perceived (very light though), not on the right (this is why I wrote NO LINES). I don't know what to think .... thanks