68 SAW
Specialist Astrograph Widefield Telescope
The 68SAW is a fast apochromatic astrograph developed by SKY ROVER, achieving a focal ratio below f/4. It is designed to meet a wide range of astrophotography needs. With a clear aperture of 68 mm, a focal length of 265 mm, and a focal ratio of f/3.9, it enables higher signal-to-noise ratio (SNR) under the same exposure time. The 68SAW also features a very wide field of view and, combined with its highly stable mechanical structure, is well suited for portable field astrophotography. The 68SAW differs from the 50SAW by adopting a design concept similar to the 110SAW. It utilizes a front-and-rear optical group configuration, which offers better stability and reliability compared to widely separated optical designs. Although its structure may resemble a typical telescope plus reducer configuration, the SAW series does not achieve its fast focal ratio by simply adding a reducer. Instead, the front and rear optical groups are integrally designed and co-optimized. At the same time, a shorter back working distance is adopted to avoid the instability associated with widely separated structures, significantly improving vibration resistance and overall reliability. During use, do not disassemble or separate the two optical groups. The front group has significant residual aberrations and cannot be used independently. During manufacturing and collimation, the front and rear groups are precisely matched. Any disassembly or improper reassembly will severely affect image quality. Please also note that the back focus distance and adjustment method differ from conventional reducer-based systems. Be sure to carefully follow the adjustment instructions to achieve optimal imaging performance.
