Yes, it is clear enough for bird watching. 

Step 1: Being careful not to touch the lens, cover the right objective lens (or close your right eye) and turn the central focusing dial until the image seen by the left eye is clear. Step 2: Cover the left lens (or close the left eye) and this time instead of turning the central focusing wheel, turn the diopter adjustment ring (located near the right eyepiece and displayed on the small image in the upper right) until the image is clear. Step 3: Finally look through the binoculars with both eyes until the image is clear and sharp. 

double-side multilayer blue coating to help repel water ,dirty 

hello,the new version of this ND filter is double-side multilayer blue coating 

You can focus clear about 6 ft as far as I know