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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 narrowband 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 street lighting, thus providing better image quality. With a full width at half maximum (FWHM) of 7nm, it achieves high contrast against the sky background, ideal for observing various emission nebulae, planetary objects, or supernova remnants.
- 7nm narrowband (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
- Double-sided optical coating with anti-reflective treatment
- Precise optical polishing ensuring a wavefront to lambda/4 and parallelism <30" arc
- Cutoff 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 street lighting for better image quality
- Compatible with other filters for high-quality images
- Precision manufacturing ensuring optimal performance
- Visual observation (country sky): Incompatible
- Visual observation (city sky): Incompatible
- Film photography: Incompatible
- CCD imaging: Excellent for enhancing nebula contrast
- Digital photography (non-modified camera): Good, even if the sensitivity of non-modified sensors is reduced in SII
- Digital photography (modified camera): Excellent for enhancing nebula contrast
- Webcam/Video (planetary): No interest
- Webcam/Video (deep sky): No interest
- ZWO S-II 7nm filter 31.75mm
