Filter ANTLIA H-ALPHA 3nm Pro Series - 36mm unmounted model

Antlia Pro 3NM HA filter

The 3nm filter can be used in areas with a lot of light pollution in order to obtain a very well contrasted and perfectly centered image at the 656.3 Nm wavelength.

Antlia's narrow bandwidth has an extremely high transmission which allows it to have a higher contrast and at the same time reduce light pollution resulting from the emission of artificial sodium and mercury lights.

The T remains stable at 656.3 Nm with 88% signal, where the filter becomes more spectrum sensitive to ensure the best signal output and an OD3 cutoff frequency (0.1%) is necessary to reduce interference from other wavelengths.

The H-Alpha filter is generally used to photograph emission nebulae, planetary nebulae, it can easily bring out the H-Alpha details of these objects.

The pro version, compared to the classical one, offers a bandwidth of 3 nm instead of 3.5 nm and is even tighter in its light distribution on very bright objects.

Each filter is individually tested and scanned to ensure that the quality meets high performance parameters. The end result is a filter that achieves excellent contrast, but at a higher production cost. We believe that the price/performance ratio is more favorable than similar premium filters on the market.

Primary use and performance

Work very well with CCD and monochrome or colored CMOS cameras, CMOS is recommended.

Suitable for deep imaging of emission nebulae, planetary nebulae and supernovae remnants.

Technical specifications:

• Basic substrate: Schott optical substrate
• Filter thickness: 3mm +/- 0.05mm for 50mm unmounted dighe.
• FWHM (full width at half-maximum): 3nm
• CWL (center wavelength): 656.3NMNNM
• Transmission point: > 88
• Blocking: > 5 OD (0.001% band blocking) @ 300-1000NM
• Surface Quality: S / D (Scratch / DIG) = 60/40 (see MIL-O-13830)
• Transmitted wavefront: lambda / 4 or better.
• Parallelism: less than 30 arcsec
• Single substrate / uncoated