Filters

I have had this filter Since December 2021

Altair Dual-Band nebula filter for astro imaging with extreme light pollution, in the city.

• This filter transmits only the H and Oiii light from emission nebulae, with almost total suppression of 99.9% OD4 on unwanted visual wavelengths.
• An extremely steep bandpass yields maximum contrast in extreme light pollution: 6.5nm FHWM centred on 500.7nm Oiii wavelength, and 7nm centred on the 656.3nm Ha wavelength.
• 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.
  SkyTech CLS-CCD filters are suitable for modified Canon DSLRs because they block UV and IR light, which are normally blocked by the built-in filters in the camera. This gives sharper stars.
  
  The CLS-CCD filter has a wider pass-band than a UHC filter, so it gives a more natural colour rendition than a UHC filter. CLS is therefore best for mild to moderate light pollution on city outskirts or suburban locations.  

I have had this filter Since July 2022

The L-Pro (L-Professional) filter is designed to improve the visibility of various deep sky objects. By selectively reducing the transmission of wavelengths of light pollutants, specifically those produced by artificial lightings including mercury vapour lamps, both high & low pressure sodium vapour lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).

The filter has high transmission in the main nebula emission lines at OIII (496nm and 500nm), H-beta (486nm), NII (654nm and 658nm), H-alpha (656nm) as well as SII (672nm), the filter is suitable for enhancing the contrast and details for both visual and photographic purposes at sub-rural area with heavy light pollution. 

Unlike UHC and CLS light pollution filters, the L-Pro is a multi-bandpass filter which offers better colour balance by maximising the transmission band. The balanced transmission allows astro images to be taken with minimal colour cast to broadband emission objects such as galaxies, reflection nebulae and globular star clusters. L-Pro is the best choice for light pollution suppression.

I bought this filter in June 2020 to help with the light polluted skies.

The SkyTech CLS-CCD (City Light Suppression) filter is designed to improve the visibility of various deepsky objects by blocking light pollution, while allowing light from deepsky objects through.

SkyTech CLS-CCD filters are suitable for modified Canon DSLRs because they block UV and IR light, which are normally blocked by the built-in filters in the camera. This gives sharper stars.

The CLS-CCD filter has a wider pass-band than a UHC filter, so it gives a more natural colour rendition than a UHC filter. CLS is therefore best for mild to moderate light pollution on city outskirts or suburban locations.  

I have had this filter since December 2020. 

SkyTech Tri-Band EOS Clip Filter for DSLR cameras (including astro-modified)

Tri-Band is the ideal light pollution filter for deep-sky imaging with colour DSLR cameras in extreme light pollution, even within city limits. 

The passband makes it compatible with fast focal ratio lenses up to F1.9.

Includes UVIR blocking for both modified and un-modified DSLR cameras plus an anti-reflection coating to reduce halos as much as possible.
 

Narrowband Bi-Colour imaging is a growing new trend in astrophotography, especially popular in light polluted areas, or for imaging in rural areas in moonlight.

Now you can capture the 3 main emission nebulae bands at the same time, whilst suppressing light pollution, moonlight, and airglow. Capture more data in less time, and open up your imaging time window - even into the summer months. These 4 nebulae emission bands are separated into two channels of red and blue/green respectively, which are easy to process in your choice of software, for amazing detail and contrast.