The Sharpstar Z4 is a professional 100mm apochromatic flatfield Petzval sextuplet with a fast focal ratio of f/5.5 and a corrected field of 36mm in diameter, making it the perfect match for APS-C cameras.
The Sharpstar Z4 includes two Extra Low Dispersion glass elements for superb correction of chromatic aberration.
Differently from standard ED refractors, the Sharpstar Z4 features a Petzval design that does not require to set the sensor to a specific distance to the last lens. That leaves the freedom to use any filter wheel, any off-axis guider or accessory without any worry to calculate the correct distance from the flattener.
With a 36mm image circle and a focal ratio of f/5.5, this is the perfect astrograph for imaging with APS-C and smaller sensors. The large rack and pinion 3.4" focuser can be rotated 360° to perfectly frame the subject and it has a reduction gear of 10:1 for precise focusing. Its long travel distance allows use as a visual instrument as well as a capable astrograph. The Z4 is natively compatible with the Prima Luce Lab Sesto Senso 2 robotic microfocuser.
All the lenses are fully multi-coated and the tube is internally flocked to reduce reflections and absorb stray light. The tube is made of CNC-machined aluminium, the rack and pinion focusing mechanism of brass and the mechanical components are engineered to provide the best rigidity, performance and durability.