A Tele Vue 35mm Panoptic in the Sky-Watcher Evostar 72ED gives 12x, a 5.67 degree true field and a 6 mm exit pupil. The worked calculation and whether it sits in the useful range.

Updated 05 September 2026.

Eyepiece and telescope pairing

Tele Vue 35mm Panoptic in the Sky-Watcher Evostar 72ED: magnification and field

What the Tele Vue 35mm Panoptic does in the Sky-Watcher Evostar 72ED, worked from the published focal lengths and apparent field.

Field of view

ring = 5.67 degrees true
dot = 6 mm exit pupil

Computed optics

Magnification
12x420 mm / 35 mm
True field
5.67 degrees68 deg / 12x
Exit pupil
6 mm72 mm / 12x
Max useful mag
170xpublished
Barrel match
2 in eyepiece in a 2 in focuser
Fits

Good fit. In the Sky-Watcher Evostar 72ED the Tele Vue 35mm Panoptic gives 12x with a 5.67 degree true field and a 6 mm exit pupil, inside the telescope's useful range.


Magnification is the telescope focal length divided by the eyepiece focal length: 420 mm divided by 35 mm is 12x. The true field of view is the eyepiece's 68 degree apparent field divided by that magnification, 5.67 degrees.

The exit pupil, the width of the light beam leaving the eyepiece, is the aperture divided by the magnification, 72 mm over 12x, which is 6 mm. That makes this a low-power, wide-field and deep-sky setting.

Questions and answers

Tele Vue 35mm Panoptic in the Sky-Watcher Evostar 72ED: magnification and field?

Good fit. In the Sky-Watcher Evostar 72ED the Tele Vue 35mm Panoptic gives 12x with a 5.67 degree true field and a 6 mm exit pupil, inside the telescope's useful range.