OPTOLONG L-Para Dual Narrowband Filter 2-inch 10nm Light Pollution Filter Astronomical Accessory

Description:
- L-Para is a brand new dual narrowband 10nm light pollution filter, with OIII (500.7nm) and H-Alpha (656.3nm) signal half bandwidth values of 10nm. This filter has a transmittance of over 85% for nebula emission lines OIII and Ha in F2 and above focal ratio systems, effectively filtering out light pollution emission lines from mercury lamps, sodium lamps, LEDs, and other sources.
- At the same time, it has excellent contrast and anti halo properties, allowing you to catch detailed and vivid nebula images. L-Para is not only suitable for ordinary optical systems, but can also be easily applied to fast optical systems such as systems for RASA and Hyperstar. Even when the light is obliquely incident, it can still maintain high transmittance, providing you with a clear and accurate shooting experience.

Features:
- Anti halo feature: the process has undergone multiple optimizations and has been repeatedly tested and verified for six months. The anti halo effect is particularly significant, improving the shooting effect of bright stars.
- Wide applicability: a dual narrowband filter suitable for all telescope systems, suitable for telescope systems ranging from fast mirrors (focal ratios F2, F2.8, F3.2, F4) to various ordinary focal ratios.
- Anti light damage ability: effectively cutting off light pollution emission line bands such as mercury lamps, sodium lamps, LEDs, etc., can be applied to light damage environments such as Porter 1-7.
- High transmittance: in F2 and above focal ratio systems, the transmission rates of nebula emission lines OIII and Ha are both greater than 85%, resulting in more efficient imaging efficiency.
- High contrast: by utilizing the high transmittance of nebula emission lines (OIII & Ha) and the high cut-off depth of light damage bands (suppressing light damage and sky background stray light), the image has higher contrast and richer details.

Based on the characteristics of celestial target emission lines and light pollution emission lines, as well as the fast and ordinary systems of telescopes, while retaining the high transparency filtering of OIII and Ha signals, the light pollution emission lines are cut off. After special design and optimization, a dual channel spectrum is formed as shown in the following figure:

Package Included:
- 1 x Filter