It is not completly black for me.

Happens with every scope.

Is it even a bug? I don't think so.

Same Issue
http://feedback.dayzgame.com/view.php?id=20196

Can confirm that!

It's not about RUNNING uphill. You should watch the arma3 video (linked by the reporter, above). It's more like a uphill jogging. And that is realisitc.

At the moment you have to walk up a hill... WTF.

Of course... if there will be a stamina system ... the uphill jogging should reduce your stamina more than just jogging on a flat surface.

Yeah. Should be like ARMA3... sometimes its just frustrating.