Pentax 20-60X Zoom XF Eyepiece For 65mm Pentax Spotting Scopes
Manufacturer Part # 70530
This Pentax zoom eyepiece is physically sized for use with the compact 65mm Pentax spotting scopes. It can also be used with the 80mm and 100mm Pentax scopes if the size and weight of the larger XW eyepieces normally used with them becomes an issue with those models. It has a 1.25" barrel, so it can also be used as a zoom eyepiece with astronomical telescopes accepting 1.25" eyepieces.
The usable eye relief ranges from 14mm at 20x to 10mm at 60x. These somewhat-short figures will vignette the field of view for those who must wear eyeglasses while observing due to astigmatism, particularly at the higher powers. Those who do not wear glasses will find the eye relief more than acceptable for unvignetted viewing, particularly when the rubber-rimmed twist-up eyecup is extended to block out ambient light and position the eye at the correct eyepoint.
The eyepiece barrel has a series of four grooves machined into the scope side of the barrel. When the eyepiece is first inserted into the scope, before tightening the eyepiece locking collar, the eyepiece should be twisted slightly until one of these grooves engages the pin in the bottom of the eyepiece receptacle. This will keep the eyepiece from twisting in place when the knurled power change collar on the eyepiece is turned to adjust the magnification.
All lens elements (a sophisticated 6 lens/4 group design) are fully multicoated with Pentax SMC (Super Multi-Coated) high transmission antireflection optical coatings for maximum light transmission and contrast. High refraction/low dispersion glass elements are used for excellent color fidelity. The eyepiece is specially sealed to be weatherproof under the worst observing conditions a birder might encounter, short of total submersion. Protective caps are provided for both ends of the eyepiece.
Tech Details:
| Barrel Size | 1.25" |
|---|---|
| Eye Relief | 10-14mm |
| Field of view 1000 yards | 110' |
| Focal Length | 19.5mm-6.5mm |
| Number of optical elements | 6 |
| Power | 20x |
| Weight | 8 oz. |
| Warranty | Limited Lifetime |