SVBONY SV115 18nm 2 O-III Filter Narrowband Cuts Light Pollution Filter for Astronomy Telescope"
Tax included.
Description:
Narrowband O-III filter is designed for nebula observation allowing 18nm bandwidth of light centered on a wavelength of 500nm through, which corresponds to O-III emission lines, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including HG vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
Feature:
1. Filter substrate is fine-optically polished to 1/4 wave and <30 parallelism over both surfaces.
2. Suitable for visual observation on most emission nebulae, planetary nebulae and supernova remnants.
3. Suitable for viewing on bright nebulae like M42 Orion Nebula in heavy light pollution.
4. Use with a large aperture telescope under clear and dark viewing conditions with good seeing.
5. Narrowband filter do not eliminate the effects of light pollution or increase the object?™s brightness. In many cases, they increase the contrast between nebula and night sky, not brightening the nebula.
6. Thin metal cells have a clear aperture of 45mm for 2' filters
7. Each filter comes with a plastic case with high pressure EVA case lining
Specification:
1. Blocking area: 400-700nm
2. Transmittance: 90% at 495.9nm and 500.7nm
3. FWHM: 18±2nm
4. Thickness: 1.85mm
5. Surface quality: 60/40 (Refer to MIL-O-13830)
6. Diameter: 2 inch
7. Weight: 31g
Package Includes:
1 x SV115 O-III 2' filter
Note: The filter is not suitable for solar observation. Do not use this filter to look at the sun. If you fail to follow the warning, you will be blind.
Details Picture:
