Squint

Do your eyes ever "shut down" after long hours on the computer?  Or after long hours on the trail searching for life?  Sometimes I have to squint my eyes to catch what it is I'm searching for.  And if I didn't squint, I might miss some of the fun shots that happen all around me.

What's that with wings on a dark shadowy branch?  What's that glistening thing sticking out on the twig?

Or that rustle in bushes?  Will it bite me?  Is that a lizard or a dinosaur up ahead?  How big do these guys get anyway?

Desert Spiny

And the birds off in the distance......like this American Avocet below.  You can definitely strain your eyes trying to focus on the shot.

During this shoot, I was by a thorny mesquite tree.  I cleared the branches away so I wouldn't poke my eyes out.

Would I get these Black Neck Stilts finally?  Was the lighting finally going to work with the shot?  It was all so far away.....

So my question to you is, "What do you do when your eyes get tired?"  or  "Do your eyes get blurry after many hours of using them with your camera?"