No prob! I'd say nothing further than a large room/a couple of streetlamps, so maybe 30 feet max -- and anything past 20 would take a few tries or just not work at all if it were really up on the edge of that radius. That's also about the same length as his body from head to tail so it's basically what he could 'reach' anyway.

Also should probably note for the second spell that he can only blind one person with it at a time.