Optolong Moon & Skyglow Light Pollution Reduction Filter - 2"
Ships by Next Business Day
Contiguous US Customers:
All items we sell ship for free within the Contiguous US. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. During checkout, you may also be shown other optional faster shipping choices.
US Customers in Hawaii and Alaska:
Free shipping applies to almost all products. A few large telescopes and mounts are excluded from this free shipping offer. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.
International Customers:
Free shipping does not apply to international orders. During check-out, you will be presented with several shipping choices and costs. However, the export of some items may be restricted outside the US due to size or manufacturer restrictions.
A. About Optolong's Moon and Skyglow FIlter
Optolong's Moon & Skyglow filter is designed to darken the background sky by blocking light transmission from skyglow (589nm) and many street light emissions from artificial light. Its high efficiency preserves image brightness, reveals more details and increases contrast of moon, galaxies, nebulae and globular star clusters.
B. Main Uses and Performance
- This is a versatile filter for visual observation and astrophotography of planetary nebulae.
- Enhance contrast of moon, galaxies, nebulae and globular star clusters.
C. Spectral Curve Transmission Characteristics
- This version does not block out infrared wavelengths (700-1100nm) so a separate IR cut-off filter is recommended for imaging applications.
D. Technical Specifications
- Both surfaces are fine optically polished, accurate to 1/4 wavelength or better, and parallel to within 30 seconds or arc.
- 2mm thick Schott B270 optical glass substrate material.
- Very high surface quality of 60/40 or better (US Military Spec MIL-O-13830).
E. Optical Coating Specifications
- Multi layer anti-reflection coated.
- Non-cementing optical substrate coating.
- Electron-beam gun evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL (central wavelength) so that there is no deviation due to temperature changes during use.
- Precise and homogeneous coatings ensure high values of desired passband and blocking of unwanted offband.
- Every single filter is tested and passed by Optolong before shipping to dealers.
F. Other
- 2" astronomy filter with standard M48x0.75 male filter thread (no female thread, so it cannot be stacked with other filters).
- Ultra-thin filter cell to minimize vignetting; clear optical aperture of 26mm.
- Precision CNC-machined metal filter cell with sand blasted black anodized finish, anti-reflection treatment, and laser engraving.
- High quality protective plastic storage case.
WARNING: Optolong filters are not designed for direct solar observation. NEVER use these filters for observing the Sun, or permanent eye and equipment damage will result.
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Hide Found a better Shipped Price on Frontend? | No |
A. About Optolong's Moon and Skyglow FIlter
Optolong's Moon & Skyglow filter is designed to darken the background sky by blocking light transmission from skyglow (589nm) and many street light emissions from artificial light. Its high efficiency preserves image brightness, reveals more details and increases contrast of moon, galaxies, nebulae and globular star clusters.
B. Main Uses and Performance
- This is a versatile filter for visual observation and astrophotography of planetary nebulae.
- Enhance contrast of moon, galaxies, nebulae and globular star clusters.
C. Spectral Curve Transmission Characteristics
- This version does not block out infrared wavelengths (700-1100nm) so a separate IR cut-off filter is recommended for imaging applications.
D. Technical Specifications
- Both surfaces are fine optically polished, accurate to 1/4 wavelength or better, and parallel to within 30 seconds or arc.
- 2mm thick Schott B270 optical glass substrate material.
- Very high surface quality of 60/40 or better (US Military Spec MIL-O-13830).
E. Optical Coating Specifications
- Multi layer anti-reflection coated.
- Non-cementing optical substrate coating.
- Electron-beam gun evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL (central wavelength) so that there is no deviation due to temperature changes during use.
- Precise and homogeneous coatings ensure high values of desired passband and blocking of unwanted offband.
- Every single filter is tested and passed by Optolong before shipping to dealers.
F. Other
- 2" astronomy filter with standard M48x0.75 male filter thread (no female thread, so it cannot be stacked with other filters).
- Ultra-thin filter cell to minimize vignetting; clear optical aperture of 26mm.
- Precision CNC-machined metal filter cell with sand blasted black anodized finish, anti-reflection treatment, and laser engraving.
- High quality protective plastic storage case.
WARNING: Optolong filters are not designed for direct solar observation. NEVER use these filters for observing the Sun, or permanent eye and equipment damage will result.
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Hide Found a better Shipped Price on Frontend? | No |
Optolong Moon & Skyglow Light Pollution Reduction Filter - 2"