I think deer temporarily focus on anything that doesn't look right , but if the suspicious object doesn't move they'll quickly forget that it's even there . I've seen this in the field too many times to doubt it . My pop-up blind has the black interior , but I quickly noticed that deer were spooking from it when they hadn't from my nearly identical previous one . The black interior turned out to be the culprit . I can't shoot a bow from this blind , so I started zipping the windows up until only "murder slits" were left . This left thin black strips across the sides , but not gaping black holes , and the deer returned to normal after I started doing that . Can they see black ? Sure they can . Does a thin black line viewed from a distance look like a silhouetted branch to a critter that has somewhat limited daytime visual acuity ? Probably . Will it spook them ? Maybe , depends on the deer . My ladder stand is flat black and looks nothing like a tree , hell the bottom of the camo seat is black . Will I be able to kill deer from it ? No question .