Violet 2024

Altair 130mm Aperture Energy Rejection filter - Ha Hydrogen Alpha only D-ERF for 5" Refractors

Product Features:

• Reduces approx. 98% of heat reaching the optics to keep Etalon from drifting off-band and protect your equipment.
• 30-40nm FHWM Bandpass at H-alpha (H) wavelength of 656.28 nm (Full Width Half Minimum) Transmission: ~90%
• UVIR blocking OD3 0.1% @400-1100nm blocking over 98% of heat to your 3rd party Etalon at eyepiece or camera end, E.g. Daystar Quark). Please note it's your responsibility to use a proper commercial Etalon with this product, and to follow the manufacturer's instructions.
• Visible light blocking: OD4 0.01% @400-700nm to reduce reflection effects and over 98% of heat.
• Diameter 140mm Thickness 12.0mm 
• Multilayer coatings with SiO2 protective overcoat.
• ERF Holder cell included with soft tip threaded knobs. Tough and very light, easy to disassemble for cleaning the filter with optical wipes. Cell does not put any tension on the optics and will not scratch or damage your telescope. It also won't alter the balance as much as an aluminium cell.

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.

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 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.

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.

• SC 2210 Colour CMOS Sensor
• 1920 x 1080 pixel resolution:
• 4 um Square Pixels
• 1/1.8-inch Optical Format
• 12-bit ADC
• 512mb DDR3 Memory
• G Sensitivity: 20100mv/lux*s
• Low Noise: : 0.47 to 3.2e-  
• Fast Frame Rate 50 FPS in 8bit mode
• Binning from 1x1 to 8x8 in either stacking or averaging modes.