Zhumell’s Z100 is about the lowest price telescope we would highly recommend for an adult user. It offers nearly all the features of a larger reflector except in a much smaller package and much lower price.
The Z100 is similar to the Orion SkyScanner, which we have also reviewed, but the focuser and finder are installed in more convenient positions for the user, the Z100 has a built-in handle, and the eyepieces included with the Z100 are a little higher quality.
The Z100 Optical Tube Overview
The Z100 is a 100mm (3.93”) f/4 Newtonian reflector. At such a fast focal ratio, you’d expect there to be coma and you’d indeed be right. It’s not noticeable with the stock 17mm and 10mm eyepieces, but with a lower magnification eyepiece like a 25mm Plossl you’ll start to spot it at the edges of the field of view.
Additionally, at f/4 precise collimation is critical for optimal performance with any reflector. Unfortunately, the folks at Zhumell have declined to offer this crucial feature and the primary mirror sits in a static, non-collimatable cell. Thankfully the scope holds collimation pretty well over time, but the lack of adjustments is mildly concerning to say ...