Optical Accessories

Altair DualBand 6nm Filter Features:

• Capture the two main emission nebulae bands at the same time, whilst suppressing light pollution, moonlight, and airglow.
• Acquire more data in less time, opening up your imaging window, even into the summer months when it isn't quite dark.
• If you have the 6nm Sii Oiii Ultra filter and the Ha Oiii version, you can capture twice the Oiii data in each imaging session and combine them for true SHO Hubble style imaging with a colour camera!
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 6nm FHWM centred on 500.7nm Oiii wavelength, and 5.5nm FHWM centred on the 671.6nm Sii wavelength.
• Halo suppression anti-reflective coating.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for the ultimate in contrast.
• Best performance at focal ratios at F4.8 or slower, however can be used as fast as F3.6, with minimal contrast impact (conservative estimate - faster may be possible). Like any dichroic filter, contrast increases as focal ratio number increases. More info about light pollution filter performance and focal ratio here.

High quality filter for CMOS photography with the following features:

• 1st band, CWL495nm FWHM35nm
• 2nd band, CWL 660nm FWHM 35nm
• 1mm thick optical glass with 30 arc sec parallelism.
• UVIR Block and Anti-Reflection Coating.

Altair DualBand 6nm ULTRA Filter Features:

• Capture two main emission nebulae bands at the same time, per filter, whilst suppressing light pollution, moonlight, and airglow.
• Acquire more data in less time, opening up your imaging window, even into the summer months when it isn't quite dark.
• If you have the 6nm Sii Oiii Ultra filter and the Ha Oiii filter combo, you can capture twice the Oiii data in each imaging session and combine them for true SHO Hubble style imaging with a colour camera!
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 6nm FHWM centred on 500.7nm Oiii wavelength, 5.5nm FHWM centred on the Sii and Ha wavelengths.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for the ultimate in contrast.
• Best performance at focal ratios at F4.8 or slower, however can be used as fast as F3.6, with minimal contrast impact (conservative estimate - faster may be possible). Like any dichroic filter, contrast increases as focal ratio number increases. More info about light pollution filter performance and focal ratio here.
• Available in 1.25" or 2" standard astronomy filter sizes. The filters have standard Astronomy compatible filter threads, and fit inside the Altair Magnetic Filter holders (with appropriate slider), and standard astronomy filter wheels. Choose the 2" version for use with the Altair Canon / Nikon DSLR lens to astro CMOS adaptors. For Hypercam 183C and 533C or 533M, 585C and smaller sensors choose the 1.25" filter. For larger sensors choose the 2" version.

Altair DualBand 4nm Filter Features:

• Capture the two main emission nebulae bands at the same time, whilst suppressing light pollution, moonlight, and airglow.
• More data in less time, opening up your imaging window, even into the summer months when it isn't quite dark yet. Capture twice the Oiii data, whilst obtaining Sii to complement the Altair Ha Oiii DualBand filter.
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 4nm FHWM centred precisely on the target wavelengths.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for halo suppression. To see the AR coating in action, please see images demonstrating the same filter with and without the AR coating on the bright star, Capella in exactly the same conditions with the same settings.
• Best performance at focal ratios as fast as F4.8, with contrast increasing as focal ratio increases. More info about light pollution filter performance and focal ratio here.
• The 2" filter has standard M48x0.75mm thread, and fits inside the Altair Magnetic Filter holders, standard 2" filter wheels, plus the Altair Canon / Nikon DSLR lens to astro CMOS adaptors. 

Altair DualBand 6nm Filter Features:

• Capture the two main emission nebulae bands at the same time, whilst suppressing light pollution, moonlight, and airglow.
• Acquire more data in less time, opening up your imaging window, even into the summer months when it isn't quite dark.
• If you have the 6nm Ha/Sii Ultra filter and the Sii/Ha version, you can capture twice the Oiii data in each imaging session and combine them for true SHO Hubble style imaging with a colour camera!
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 6nm FHWM centred on 500.7nm Oiii wavelength, and 5.5nm FHWM centred on the 656.28nm Ha wavelength.
• Halo suppression anti-reflective coating.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for the ultimate in contrast.
• Best performance at focal ratios at F4.8 or slower, however can be used as fast as F3.6, with minimal contrast impact (conservative estimate - faster may be possible). Like any dichroic filter, contrast increases as focal ratio number increases. More info about light pollution filter performance and focal ratio here.

• This finder is right angled for more comfort, with a corrected field (i.e. not mirror-reversed like other finders), so objects actually match their orientation in your star chart.
• The focuser can also be rotated 360° and locked in seconds (requiring some re-alignment afterwards). The 10mm larger objective and a little extra power compare to 8x50 finders, yet has almost the same size and weight.
• The included quick-release finder base has 4x 4mm slotted holes in the base allowing you to fit it to most telescopes on the market. (The mini-dovetail wedge on the bracket will fit any GSO or Skywatcher telescope directly in fact but we suggest you use the included base if it fits the tube, because it has 2x clamping screws, for better alignment).
• The CNC machined bracket is light yet rigid to keep alignment. Nylon tipped screws do not damage the durable high quality and moisture resistant powder coated aluminium tube.
• All objective lenses are anti-reflection coated and the tube and dewshield are internally blackened to increase contrast. The included illuminator has a variable setting, which illuminates the cross hairs in the eyepiece. The included eyepiece has a dark field illuminated cross-hair, so you can easily see it glowing faintly against the background sky, an upgrade for standard finders with dark cross-hairs.
• The high quality 1.25 FMC illuminated eyepiece has good eye relief for glasses-wearers, and a wide field of view. It has a side-port to screw in the included variable darkfield illuminated reticule, and the finder can be very easily focused, using the included helical focuser integrated with the prism diagonal.

The new TriBand V2 Filter

• Anti-Halo coating on both surfaces to reduce reflection artefacts from reducers and camera lenses.
• Increased blocking of UV, IR and unwanted visual range wavelengths. UV OD7 (T0.00001%) Visual OD5 (T0.001%) and IR OD4 (T0.01%) for the ultimate in skyglow blocking. This is an order of magnitude better than foreign filters.
• Higher transmission % of desired wavelengths Ttop 93% (Average 5% higher transmission of target wavelengths than V1). In general a 5% gain on foreign filters.
• Ha at 14nm and Oiii at 34nm FWHM for with less tail-off to reduce unwanted light pollution, whilst keeping transmission high compared to the V1.

Altair DualBand 6nm Filter Features:

• Capture the two main emission nebulae bands at the same time, whilst suppressing light pollution, moonlight, and airglow.
• Acquire more data in less time, opening up your imaging window, even into the summer months when it isn't quite dark.
• If you have the 6nm Sii Oiii Ultra filter and the Ha Oiii version, you can capture twice the Oiii data in each imaging session and combine them for true SHO Hubble style imaging with a colour camera!
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 6nm FHWM centred on 500.7nm Oiii wavelength, and 5.5nm FHWM centred on the 671.6nm Sii wavelength.
• Halo suppression anti-reflective coating.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for the ultimate in contrast.
• Best performance at focal ratios at F4.8 or slower, however can be used as fast as F3.6, with minimal contrast impact (conservative estimate - faster may be possible). Like any dichroic filter, contrast increases as focal ratio number increases. More info about light pollution filter performance and focal ratio here.

Altair DualBand 6nm ULTRA Filter Features:

• Capture two main emission nebulae bands at the same time, per filter, whilst suppressing light pollution, moonlight, and airglow.
• Acquire more data in less time, opening up your imaging window, even into the summer months when it isn't quite dark.
• If you have the 6nm Sii Oiii Ultra filter and the Ha Oiii filter combo, you can capture twice the Oiii data in each imaging session and combine them for true SHO Hubble style imaging with a colour camera!
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 6nm FHWM centred on 500.7nm Oiii wavelength, 5.5nm FHWM centred on the Sii and Ha wavelengths.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for the ultimate in contrast.
• Best performance at focal ratios at F4.8 or slower, however can be used as fast as F3.6, with minimal contrast impact (conservative estimate - faster may be possible). Like any dichroic filter, contrast increases as focal ratio number increases. More info about light pollution filter performance and focal ratio here.
• Available in 1.25" or 2" standard astronomy filter sizes. The filters have standard Astronomy compatible filter threads, and fit inside the Altair Magnetic Filter holders (with appropriate slider), and standard astronomy filter wheels. Choose the 2" version for use with the Altair Canon / Nikon DSLR lens to astro CMOS adaptors. For Hypercam 183C and 533C or 533M, 585C and smaller sensors choose the 1.25" filter. For larger sensors choose the 2" version.

Altair DualBand 6nm Filter Features:

• Capture the two main emission nebulae bands at the same time, whilst suppressing light pollution, moonlight, and airglow.
• Acquire more data in less time, opening up your imaging window, even into the summer months when it isn't quite dark.
• If you have the 6nm Ha/Sii Ultra filter and the Sii/Ha version, you can capture twice the Oiii data in each imaging session and combine them for true SHO Hubble style imaging with a colour camera!
• Extremely steep bandpass yields maximum contrast in extreme light pollution: 6nm FHWM centred on 500.7nm Oiii wavelength, and 5.5nm FHWM centred on the 656.28nm Ha wavelength.
• Halo suppression anti-reflective coating.
• Can be used with One Shot Colour (OSC) CMOS or mono astronomical cameras for luminance data.
• Includes UVIR blocking for both modified and un-modified DSLR cameras, plus an anti-reflection coating for the ultimate in contrast.
• Best performance at focal ratios at F4.8 or slower, however can be used as fast as F3.6, with minimal contrast impact (conservative estimate - faster may be possible). Like any dichroic filter, contrast increases as focal ratio number increases. More info about light pollution filter performance and focal ratio here.