High efficiency, favorable price!

This compact zoom eyepiece from the Astro-Professional series has a zoom range from 7.2mm to 21.5mm. When designing the eyepiece great emphasis was placed on a functional zoom eyepiece with good optical and mechanical properties. The eyepiece can not be compared with "normal" zoom eyepieces. The picture is much more contrasty and sharper. The mobility of the zoom drive allows the zoom range to be precisely adjusted. The eyecup can be individually adjusted to the viewer in height and is thus optimally suited for eyeglass wearers (Twist Up Style). The anti-reflection protection consists in this eyepiece of a special aperture system and blackened lens edges.

Technical data of the eyepiece series Zoom:

    Zoom eyepiece focal length 7.2mm to 21.5mm
    53-40° field of view
    Lens with 7 elements of 4 groups each
    Highest quality broadband multi-compensation of the lenses
    Suitable for wearing glasses, retractable eyecup (Twist Up Style)
    Blackened lens edges, elaborate glare design against stray light
    Telescope mount 31.75mm (1.25")
    Eye distance: 15mm

Information:

For observation with a telescope different eyepieces are required. For lunar, deep sky / galaxy observations a rather small magnification is needed. For planetary observations, however, a very high magnification of:

30-50x magnification as an overview eyepiece and for lunar observations,
70-100 times for lunar, galaxy and fog observations,
140-200 times for planetary observations.

Our recommendation: Never exceed the telescope magnification by more than 2 times the lens diameter.

An example: If a telescope has a 90 mm lens, you should not exceed a 180x magnification.

The magnification is calculated as follows: Telescope focal length in mm / eyepiece in mm
An example: Telescope with 1000mm focal length / eyepiece with 10mm = 100x magnification in the telescope