ZWO NARROWBAND FILTERS 31mm Ring there may be inconsistencies in

there may be inconsistencies in the finish

Type Truss tube Dobsonian

58 mm (minor axis)

By using 2 clamps you can build a side-by-side system on the same PLUS Losmandy or Vixen bar

The dew heater avoids the problem of dew condensation on the optical window of the sensor

ZWO NARROWBAND FILTERS 31mm Ring there may be inconsistencies inThese new 31mm narrowband filters are not mounted in a cell and they are designed to fit on the ZWO filter wheels. Narrowband filters enhance the contrast of emission and planetary nebulae. These peculiar nebulae emit light only in specific wavelengths (H; OIII ; SII) and the narrowband filters have the property to reject all light outside these bands. The passing band or "window" of these filters is 7nm wide. Considering that the visible light