Antlia 4.5nm Narrowband Sulfur II (SII) EDGE Imaging Filter - 31mm Round Unmounted
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.
Application and Performance:
- High transmittance and narrow bandwidth to maximize contrast
- Steep spectral profile minimizes halos around bright stars
- A single substrate to eliminate internal reflections
- Narrowband Objects: SII Emission Nebulae, Planetary, Wolf-Rayet Nebulae and Supernova Remnants
- Use in light polluted areas and dark sites
- Extend imaging time when the moon is up
- Antlia narrowband EDGE filters can be used down to f/3 systems with minimal loss of signal
- Edge blackened to eliminate internal reflections from stray light
- Superior optical reliability reduces post image processing
- This filter is only effective for deep sky objects that contain SII emissions
The Antlia SII EDGE narrowband filter optimizes the FWHM (full width half maximum) to 4.5nm bandpass. The suppression of optical density (OD) 5 on unwanted wavelengths and the excellent transmittance characteristics found in the Antlia 3nm Pro series has been incorporated into the 4.5nm EDGE narrowband filters. The result is that these filters deliver superior SNR (signal to noise ratio) and better contrast in your images.
Antlia SII 4.5nm EGDE filters are designed to deliver high transmittance at the 671.6nm line that provides you with the maximum signal to reveal the faintest SII nebulae structures, planetary nebulas and supernova remnants.
Conventional broader narrowband filters cause a heavy loss in transmission due to the strong Center Wavelength (CWL)-shift. Antlia guarantees T>90% within 1nm range of the center bandwidth for f/4.5 or slower scopes. Blue-shift data also shows that Antlia 4.5nm EDGE filters can be used with nearly all systems as fast as f/3 with minimal loss in emission signal and meets the requirements of fast optics. Hence, 4.5nm EDGE narrowband filters can guarantee high transmittance for working with both long focal ratios and fast optical systems.
When Antlia designs filters for astronomy imaging systems, they look at how they will work together with optical systems, carefully designing the out of band blocking rate, transmittance and band-pass parameters to achieve an optimum result. Each filter is individually tested and scanned by strict QC methods to ensure that the quality meets the high-performance parameters. The result is that Antlia is known for designing filters for astrophotography that achieve exceptional quality and performance parameters at affordable prices. We believe the price to performance ratio compares more favorably than similar premium filters in the market.
Technical Data:
- Schott optical substrate
- 31mm round unmounted (2mm thickness +/-0.05mm). Additional sizes available separately
- Surface Quality: 60/40 (Refer to MIL-O-13830)
- 2 sides fine-optically polished to ensure accurate 1/4 or better wavefront
- Parallelism: less than 30 arcsec
- Center-Wavelength of Antlia SII 4.5nm filter: 671.6nm
- Peak transmission > 90%
- Blocking: > 5 OD (0.001%) @ 300-1000nm
- 2 sides Multi-layers anti-reflection coating
- Single / Non-glued substrate
Filter Ring:
- None. 31mm round diameter, unmounted
Not Recommended:
- Solar Observing and imaging
- Visual observation
- DO NOT LOOK AT THE SUN WITH ANTLIA FILTERS. Serious eye damage will result if you fail to observe the warning.
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Hide Found a better Shipped Price on Frontend? | No |
Application and Performance:
- High transmittance and narrow bandwidth to maximize contrast
- Steep spectral profile minimizes halos around bright stars
- A single substrate to eliminate internal reflections
- Narrowband Objects: SII Emission Nebulae, Planetary, Wolf-Rayet Nebulae and Supernova Remnants
- Use in light polluted areas and dark sites
- Extend imaging time when the moon is up
- Antlia narrowband EDGE filters can be used down to f/3 systems with minimal loss of signal
- Edge blackened to eliminate internal reflections from stray light
- Superior optical reliability reduces post image processing
- This filter is only effective for deep sky objects that contain SII emissions
The Antlia SII EDGE narrowband filter optimizes the FWHM (full width half maximum) to 4.5nm bandpass. The suppression of optical density (OD) 5 on unwanted wavelengths and the excellent transmittance characteristics found in the Antlia 3nm Pro series has been incorporated into the 4.5nm EDGE narrowband filters. The result is that these filters deliver superior SNR (signal to noise ratio) and better contrast in your images.
Antlia SII 4.5nm EGDE filters are designed to deliver high transmittance at the 671.6nm line that provides you with the maximum signal to reveal the faintest SII nebulae structures, planetary nebulas and supernova remnants.
Conventional broader narrowband filters cause a heavy loss in transmission due to the strong Center Wavelength (CWL)-shift. Antlia guarantees T>90% within 1nm range of the center bandwidth for f/4.5 or slower scopes. Blue-shift data also shows that Antlia 4.5nm EDGE filters can be used with nearly all systems as fast as f/3 with minimal loss in emission signal and meets the requirements of fast optics. Hence, 4.5nm EDGE narrowband filters can guarantee high transmittance for working with both long focal ratios and fast optical systems.
When Antlia designs filters for astronomy imaging systems, they look at how they will work together with optical systems, carefully designing the out of band blocking rate, transmittance and band-pass parameters to achieve an optimum result. Each filter is individually tested and scanned by strict QC methods to ensure that the quality meets the high-performance parameters. The result is that Antlia is known for designing filters for astrophotography that achieve exceptional quality and performance parameters at affordable prices. We believe the price to performance ratio compares more favorably than similar premium filters in the market.
Technical Data:
- Schott optical substrate
- 31mm round unmounted (2mm thickness +/-0.05mm). Additional sizes available separately
- Surface Quality: 60/40 (Refer to MIL-O-13830)
- 2 sides fine-optically polished to ensure accurate 1/4 or better wavefront
- Parallelism: less than 30 arcsec
- Center-Wavelength of Antlia SII 4.5nm filter: 671.6nm
- Peak transmission > 90%
- Blocking: > 5 OD (0.001%) @ 300-1000nm
- 2 sides Multi-layers anti-reflection coating
- Single / Non-glued substrate
Filter Ring:
- None. 31mm round diameter, unmounted
Not Recommended:
- Solar Observing and imaging
- Visual observation
- DO NOT LOOK AT THE SUN WITH ANTLIA FILTERS. Serious eye damage will result if you fail to observe the warning.
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Hide Found a better Shipped Price on Frontend? | No |
Antlia 4.5nm Narrowband Sulfur II (SII) EDGE Imaging Filter - 31mm Round Unmounted