Nikon 15-45x Zoom Eyepiece for Sky & Earth Spotting Scopes #7675 fits both the 60mm and 80mm Nikon Sky&Earth spotting scopes. It has a surprisingly flat field of view, with low astigmatism and low distortion - optical qualities usually found only in the eyepieces used on considerably more expensive scopes. Contrast is also quite good. A soft rolldown rubber eyecup protects eyeglasses from scratches and nicks. The eye relief is a respectable 15mm at low power for virtually unvignetted use with eyeglasses, although it does drop as the magnification increases.

Magnification and field of view vary, depending on the scope being used.

With the 60mm Sky - Earth scopes, the zoom set at 15x will give a 133' field at 1000 yards and 15mm of eye relief. At a zoom setting of 30x the scope has a 95' field at 1000 yards and 12mm of usable eye relief. At 45x it has a 64' field at 1000 yards and 10mm of usable eye relief.

With the 80mm Sky and Earth scopes, the zoom set at 15x actually yields 20x. It will give a 100' field at 1000 yards and 15mm of eye relief. At a zoom setting of 30x the scope is actually performing at 40x, with a 71' field at 1000 yards and 12mm of usable eye relief. At a marked setting of 45x, an 80mm scope actually yields 60x, with a 48' field at 1000 yards and 10mm of usable eye relief.

As with any zoom eyepiece, the precise focal length or magnification of the Nikon zoom at any given point in time is not all that important. The experienced observer invariably adjusts the zoom magnification to match the seeing conditions and object size as he looks through the eyepiece, rather than first setting the zoom to an arbitrary focal length value according to the scale on the side of the eyepiece and using it at that power no matter what the seeing conditions. The flexibility of a zoom to instantly match the magnification to changing lighting or seeing conditions is one of the zoom eyepiece's chief advantages.

Specifications for Nikon 7675 15-45x Zoom Eyepiece for Sky and Earth Spotting Scopes:

Magnification:		15-45x with 60mm scopes  20-60x with 80mm scopes
Angle of View:		2.5° with 60mm scopes at 15x only (unspecified otherwise)  1.9° with 80mm scopes at 20x only (unspecified otherwise)
Field-of-View (@ 1000 Yds):		133' (44 m at 1000 m) with 60mm scopes at 15x only (unspecified otherwise)  99' (33 m at 1000 m) with 80mm scopes at 20x only (unspecified otherwise)
Exit Pupil Diameter:		4.0-1.3mm
Eye Relief:		12mm
Relative Brightness:		16.0-1.8
Twilight Factor:		30.0-52.0 with 60mm scopes  40.0-69.3 with 80mm scopes
Weatherproofing:		Water resistant
Dimensions:		3.1 x 1.5" (78 x 38mm) LxW
Weight:		0.20 lb (90 g)

Features of Nikon 7675 15-45x Zoom Eyepiece for Sky Earth Spotting Scopes:

• 25-Year Warranty

Package Contents:

• Nikon 15-45x Zoom Eyepiece for Sky and Earth Spotting Scopes 7675
• Caps
• 25-Year Warranty

Nikon 15-45x Zoom Eyepiece for Sky and Earth Spotting Scopes - 7675 Rating & Reviews