All the boas are variable by location, but here in Costa Rica this is the typical coloration for this species. Kinda bland brownish for two thirds of the way back, and then a nice sorta bulls eye pattern and then a black tail tip. They also have orange eyeshine at night which makes them a bit easier to spot, but after you are looking at them with a headlamp the pupil goes down to it's vertical slit and they look like a venomous viper which they are not. However, while these aren't venomous I would recommend avoiding grabbing them. They have extremely sharp recurved teeth and if they decide to take a bite there will be a lot of blood involved.
Of note, the snake has a tick attached above its right eye.