QHY 30mm f/4.3 MiniGuidescope - 100062 Antlia Dual & Tri-Band Filters The ZWO SII Filter has

The ZWO SII Filter has a bandpass of 7 nm and passes light at 672nm wavelength at a transmission rate of 90%

This ring is compatible with the TSN-DA20

so you spend less time managing limits and more time imaging and exploring the night sky

Real-time Periodic Error Correction (RPEC)

Internal hard stops for both axes prevents cable tension and tripod strike

QHY 30mm f/4.3 MiniGuidescope - 100062 Antlia Dual & Tri-Band Filters The ZWO SII Filter hasWhen the pixels of a guide camera becomes small and QE becomes high, you may not need a big guide scope; smaller pixels can detect the guide error in a shorter focal length. Furthermore, when the focal length is reduced, the FOV becomes larger, so it is easier to find bright guide stars. The QHYCCD miniGuideScope is based on just this idea. The miniGuideScope is a 30mm f 4. 3 (130mm FL) ultra small telescope. It has no complex focal adjust system.