Jim BodieI have a very definitive way to tell if I am quite tired and have been staring at a computer screen far far too much. My eyes go to shit when I'm overtired and they've been worked too much. For things that I normally can use them, my +1.00 reading glasses aren't cutting it right now. I have to go to my +1.50 reading glasses. I usually only use these for reading the books with the smaller print.
My eyes will be fine after a night's sleep. Which I will soon get.