ZWO 7nm NARROWBAND FILTER SET Cooled SWDOB250CGT

SWDOB250CGT

The PRO RC's represent a step forward in state of the art of professional instruments

a flat field and a small obstruction caused by the secondary mirror

1mm AR protecting window are listed as below:

Beech wood specially treated for outdoor use

ZWO 7nm NARROWBAND FILTER SET Cooled SWDOB250CGTZWO 7nm 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 spectrum is between 380nm and 740nm, a 7nm filter would block 98% of the unwanted light. As a result, the signal