Kowa TE-14WD 30x WA Eyepiece can calculate the difference between

can calculate the difference between two points

Only ambient air is pulled inside the blower

and moisture from entering the camera body and landing on the camera sensor

White Phosphor Tubes can be set to read white hot or black hot and are considered to be more restful on the user's eyes

While they do reduce visual acuity

Kowa TE-14WD 30x WA Eyepiece can calculate the difference betweenThe TE 14WD (TSE 14WD) is a 30x, fixed magnification, wide angle eyepiece designed for use on Kowas TSN 600 and TSN 660 series spotting scopes. The TE 14WD eyepiece has 20 mm of eye relief, and field of view of about 126 feet at 1000 yards. When fixed to TSN 600 or TSN 660 spotting scopes, the eyepiece is waterproof. The TE 14WD eyepiece may be used on TSN 880 770 series scopes by means of the TSN EC3 adaptor.