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ZWO S-II 7nm 31.75mm Filter for Astrophotography - ZWO
ZWO S-II 7nm 31.75mm Filter for Astrophotography - ZWO
SKU: zwo-zwsii7_125
Available within 7 days
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The ZWO S-II 7nm narrow band filter is specially designed for astrophotography, focusing on a wavelength of 672nm. It can be used in combination with H-Alpha and O-III filters to achieve images comparable to those from the Hubble Space Telescope. By selectively reducing the transmitted wavelengths, this filter eliminates the effects of public lighting, thereby offering better image quality. With a full width at half maximum (FWHM) of 7nm, it provides high contrast against the sky background, making it ideal for observing various emission nebulae, planetary objects, or supernova remnants.
- 7nm narrow band (FWHM)
- Optimized transmission wavelength at 672nm
- Compatible with H-Alpha and O-III filters
- CNC-machined aluminum cell for high precision
- Available in 4 sizes: 31.75mm, 31.7mm, 50.8mm, and 36mm unmounted circular
- High-quality Schott glass with a thickness of 1.85mm
- Dual-sided optical coating with anti-reflection treatment
- Precise optical polishing ensuring a wavefront of lambda/4 and parallelism <30" arc
- Cut-off in the infrared (700/1100nm)
- Offers high contrast against the sky background
- Ideal for observing emission nebulae, planetary objects, and supernova remnants
- Effectively eliminates the effects of public lighting for better image quality
- Compatible with other filters for high-quality images
- Precision manufacturing ensures optimal performance
- Visual observation (rural sky): Incompatible
- Visual observation (urban sky): Incompatible
- Film photography: Incompatible
- CCD imaging: Excellent for enhancing nebula contrast
- Digital photography (unmodified camera): Good, although unmodified sensor sensitivity is reduced in SII
- Digital photography (modified camera): Excellent for enhancing nebula contrast
- Webcam/Video (planetary): Not applicable
- Webcam/Video (deep sky): Not applicable
- ZWO S-II 7nm filter 31.75mm
