The GSO 4.5" f/4.125 Carbon Imaging Newtonian is a fast, compact reflector telescope designed for deep sky astrophotography. The newly updated linear bearing focuser is natively compatible with the ZWO EAF electronic focusing motor.

Compared to a common f/5 Newtonian, the photographic exposure with an f/4 system is 40% shorter, making it a great time saver. This instrument is ideal for astrophotography and when used with an additional coma corrector, will deliver sharp images across a large flat field. GSO is currently developing a dedicated coma corrector for this telescope.

The 1.25" dual-speed Crayford focuser features an M42 (T2) thread for easy connection to common imaging systems. It operates at two speeds due to the 10:1 reduction mechanism for an extra fine focusing adjustment, which is paramount for astrophotography and high resolution observations. No custom bracket is required to attach the ZWO EAF.

The secondary mirror is oversized in order to have a fully illuminated field and to avoid vignetting. It is collimatable by using 3 grub screws and the offset can be adjusted by using the central spring loaded screw. The primary mirror features a centre dot for quick and straightforward collimation.

Both mirrors are made of BK7 glass which has a low thermal expansion coefficient. That means that the precise optical surfaces of the mirrors remain the same while the glass cools down over the night. 

The carbon-fibre tube is internally blackened to avoid internal reflection, enhance contrast and to absorb stray light.

Specifications

 In the box

• GSO 4.5" f/4.125 carbon OTA
• Vixen style bar
• Finder shoe bracket