What is the primary purpose of the ZWO AR Window?
It acts as a protective cover for your camera's sensor. It shields the delicate sensor from dust, humidity, and potential physical contact without degrading image quality, thanks to its 1/4λ flatness and AR coatings.
Which ZWO cameras use each AR Window size?
ZWO lists the D21 for the ASI120, ASI178, ASI290, ASI224MC, ASI385, ASI185MC, ASI220, ASI462, ASI662, ASI678, ASI664 and ASI715 series; the D25 for the ASI174 series; and the D60 for the ASI071MC Pro, ASI6200MM Pro and ASI2600MM Pro/Duo. Always confirm your specific camera model before purchasing.
Will installing an AR Window change my focus point?
Replacing a window with one of the same type and thickness should not change your focus. ZWO lists the D21 and D25 windows at 1.1mm thick and the D60 at 2mm.
How do I install the ZWO D21 AR Window on my ASI290MM Mini?
Installation involves carefully unscrewing the front nosepiece of the camera to access the sensor chamber. The old window (if present) can be gently removed, and the new D21 AR window is dropped into its place. Ensure the environment is as dust-free as possible during the process.
Can I use the D21 AR Window instead of a UV/IR cut filter for planetary imaging with my ASI224MC?
No, this is not a filter. The AR window is a clear, AR-coated window designed for protection and maximum light transmission. For planetary imaging with a color camera like the ASI224MC, you still need a separate UV/IR Cut (Luminance) filter to ensure correct color balance and sharpness, as the sensor is sensitive to out-of-band light.
How should I clean the ZWO D21 AR Window?
Treat it like any high-quality optic. First, use a clean air blower to remove any loose dust. For fingerprints or smudges, use a microfiber cloth with a small amount of a dedicated optical cleaning solution. Wipe gently in a circular motion from the center outwards to avoid scratching the AR coatings.
