thanks guys
For painting I don't use magnification lens, I'm very mole from far distance, therefore at 20 cm (painting distance) I see perfectly all details
For eyes, I start making a white "large" circle, then I make a vertical black line (the pupil) : this is the most difficult part, it's hard to allign the two eyes and often I have to repeat the process due to "cross-eyed warrior". After that I reduce the circle with orizontal brown painting above and below, to create the "real eye" effect.
It's not always straight-forward, sometime it goes wrong and I have to repeat all the process, but patience is one of the characteristics we must have in our hobby