Ok, thank you, i will read this article but if i understand: it might says that when we introduce a logo in illustrator, we are forced to do it with a .svg format???
I'm new on illustrator and i used to use inkscape and gimp, do you know why i don't have this problem with the same image in inkscape and gimp
? And i'm sure that Illustrator is very better than Inkscape!!!
You are not forced to use a vector image, but it's better if you do.
If you want to use a raster image it has to be a sufficient resolution.
I don't know why you don't see the effect in GIMP or Inkscape. Maybe the zoom level is different and maybe you scale it differently. And maybe Inkscapes or GIMP's screen rendering is different.
You have to learn about resolution. You have to fully understand the concept. You have to fully understand what effective resolution is and also how all this is connected to the zoom level. Also you have to understand the necessities of printing and of screen design.