Astronomy Specialist

ANTLIA ALP-T SII & Hb 3.5nm DUAL BAND FILTER

$589.00
SKU: AN-ALP-T2-HbSII-3nm

Antlia

  • 3.5 nm

FREE SHIPPING


 

The new Antlia ALP-T Golden S-II and H-beta 3.5nm Dual Band filter is specifically designed for astrophotography with colour DSLR, CMOS or CCD cameras in areas with heavy light pollution. Its two 3.5nm passing bands are exceptional at isolating nebulae emissions in SII and Hb. Images taken through this filter can be easily combined with those taken through the Ha & OIII ALP-T to create stunning full-colour Hubble Palette pictures.

Currently this filter is only available in 2" mounted.

The optical density of 4.5 suppresses unwanted wavelengths from light pollution, moonlight and skyglow, resulting in superior signal-to-noise ratio and better contrast.

Like all Antlia filters, the Golden Dual Band filter has excellent halo suppression, making imaging of targets surrounded by bright stars such as the Horsehead Nebula pain-free.

 

 

  • It blocks the artificial light from mercury vapour lamps, both high and low pressure sodium vapour lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).
  • Maximum transmission of the main nebula emission lines at SII (672.4nm) is >90% and H-beta (486.1nm) is >85%. Good signal is still achievable with optics as fast as f/3.
  • Two transmission bands with a bandpass of 3.5nm. OD4.5 @ 300-1100nm.
  • Ideal for urban areas with extreme light pollution.
  • It incorporates an IR/UV-Cut filter that is necessary in astrophotography, especially for astronomy cameras that are sensitive to the infrared radiation.
  • Ultra-thin filter cell to maximise the compatibility with most filter drawers.
  • Ideal flat-top and moderate bandpass reduces spectrum down shifts.
  • Data taken with this filter can be combined with that taken with the ALP-T H-alpha & OIII filter to create Hubble Palette images.

To even further enhance the contrast, and suppress the stray light and internal reflections, Antlia applies edge-blackening coating on each filter. Each filter is individually tested to ensure a high quality standard. The tight tolerance of the filters substrate assure a maximum deviance of ±0.05 from specifications making these filters parfocal.

DO NOT LOOK AT THE SUN WITH ANTLIA FILTERS. Serious eye damage will occur.

Specifications

 

Passing band 3.5 nm +0.5 / -0.5 nm (FWHM)
Glass thickness

2.0 mm ±0.05

Optical flatness

1/4 λ (wavefront)

Bandpass transmission H-a >90%, OIII >85%
Off-band transmission OD4.5 @ 300-1100 nm
Coating Double-sided multilayer nano-coating
Surface quality 60/40 (in accordance with US military watch MIL-O-13830)
Parallelism 30"
SKU
2" - AN-ALP-T2-HbSII-3nm

 

ANTLIA ALP-T SII & Hb 3.5nm DUAL BAND FILTER

$589.00

Optical design

Image circle

Focal ratio

Aperture

Focal length

Optical thickness

Threads

Cooled

Colour or Mono

Pixel size

Sensor dimensions

Resolution

Sensor diagonal

Quantum efficiency

Read noise

Fullwell capacity

Bit depth

FPS

Camera backfocus

Filter size

Filter size

Bandpass (FWHM)

3.5 nm

Bandpass (FWHM)

3.5 nm

Glass thickness

2 mm

Mount type

Payload capacity

Latitude range

Dovetail saddle

Slew speed

Encoders

Periodic error correction

Counterweight shaft

Azimuth adjustment range

Internal diameter

Illuminated diameter

Compatible telescope external diameter

Weight

Length

Width

Height

View product