Optolong LRGB filter 1.25" Optolong's LRGB set splits the spectrum into luminance, red, green and blue for colour imaging with monochrome cameras. Steep band edges cut UV and IR, OIII falls in both the blue and green filters, and the gap between green and red blocks the 589 nm sodium line. The filters are parfocal (1:1:1 RGB).
Manufacturer model: Optolong LRGB 1.25" · Specifications checked against manufacturer data on 2026-11-03
Optolong's LRGB set splits the spectrum into luminance, red, green and blue for colour imaging with monochrome cameras. Steep band edges cut UV and IR, OIII falls in both the blue and green filters, and the gap between green and red blocks the 589 nm sodium line. The filters are parfocal (1:1:1 RGB).
Specifications
Format
1.25" mounted
Set contents
Luminance (UV/IR cut), Red, Green, Blue
Substrate
B270
Thickness
1.85 mm
Average transmission
>90%
Blocking range
350–1050 nm
Light-pollution line blocking
>99%
Parfocal
RGB 1:1:1
Surface quality
60/40
Transmitted wavefront
λ/4 RMS
Parallelism
30"
Coating
Multi-layer anti-reflection coating on a non-cemented substrate, applied by ion-assisted deposition for durability and a stable centre wavelength with temperature.
Optolong LRGB filter 1.25" Optolong's LRGB set splits the spectrum into luminance, red, green and blue for colour imaging with monochrome cameras. Steep band edges cut UV and IR, OIII falls in both the blue and green filters, and the gap between green and red blocks the 589 nm sodium line. The filters are parfocal (1:1:1 RGB).
Manufacturer model: Optolong LRGB 1.25" · Specifications checked against manufacturer data on 2026-11-03