According to the users’ and market demands, Sharpstar has newly launched an integrated astrograph—Z4. It has an aperture of 100mm and the focal ratio is f/5.5. Z4 is a sextuplet astrograph with three pieces of lens at the front and three pieces at the back, and two of them are ED glasses. Just like other series of Sharpstar astrographs, Z4 is designed as self-flattened so there is no need to calculate the back focus. You can just make the target stay at the focus, and the optical system is perfect for imaging.
The appearance of Z4 breaks through the previous style of Sharpstar with its matte gray coating. Light gray lens tube plus dark gray focuser and tube ring, make the astrograph looks calm but vibrant. The tube ring has a handle on the top which is easy to carry and assemble. The handle is designed as a slot on which you can mount a finder base, etc.
Z4 uses a large 3.4” focuser with a 1:10 fine adjustment knob and a 360° rotator for easy focusing and angle adjustment. It has M86, M68, M54, M48 adapters, and the M48 one has an internal thread that can fit 2” filters. And a 300mm Vixen-style dovetail plate, makes it easier to balance on the equatorial mount.
Objective lens：sextuplet fully air-spaced APO (including two ED glasses)
Back focus:55mm（from the M48 thread）
Gross weight：5.6kg（without the aluminum box）
Rear-end thread ：M48×0.75 male thread
M54×0.75-M48×0.75（with M48×0.75 filter thread）
Standard package items：a tube ring, a dovetail plate, a handle, a 4-piece photographical adapter， a warranty，a manual
Sharpstar Z4 100mm f5.5 Astrograph and Askar Color Magic 3nm Duo Narrow Band Filter