Astronomik 1.25″ LRGB filter set
If you do astrophotography with a monochrome CCD or CMOS camera and want to produce accurate, technically precise color images of deep sky objects, the Astronomik LRGB filter set in 1.25″ size is exactly what you need. This set combines four interference filters - a luminance filter (L) with UV and IR blocking, and three color filters: R (red), G (green), and B (blue) - into a complete solution for the classic LRGB workflow.
High-quality interference filter technology
Astronomik filters are made using modern thin-film interference coating technology applied to optical glass. This ensures highly precise and stable spectral characteristics. Each filter offers high transmission within its defined passband while reliably blocking unwanted wavelengths.
The filters feature sharp transition band edges, so when combining channels into a final color image, there are no overlaps or color artifacts. The glass substrates are precisely flat to prevent degradation of star images or focus shift when switching between filters - a critical factor for photometry and accurate channel stacking.
What is included in the set
- Luminance filter (L) - blocks UV and IR, passes the full visible spectrum
- Red filter (R) - precisely defined red channel
- Green filter (G) - precisely defined green channel
- Blue filter (B) - precisely defined blue channel
Luminance filter (L)
The luminance filter is a key part of the set. Its purpose is not to narrow the passband in the visible range, but to effectively block ultraviolet and infrared radiation. Modern camera sensors are very sensitive to UV and IR light, but these wavelengths introduce blurring and chromatic errors into the final image.
The L filter allows you to take luminance exposures with maximum transmission across the visible spectrum, while preserving the sharpness needed to capture fine detail in nebulae, galaxies, and star clusters.
Color filters R, G, and B
The R, G, and B color filters are designed so their spectral response closely matches the standard color model used in astrophotography processing. Thanks to precisely defined transition bands and high peak transmission - typically over 90% at the center of the passband - these filters allow natural color reproduction even of objects with complex emission structures.
A well-balanced LRGB set is the foundation for images that are not only visually impressive, but also faithful to the physical reality of the objects being photographed.
Who is this set for
LRGB filters for monochrome CCD and CMOS cameras are the standard choice for both observatories and advanced amateur astrophotographers who want full control over every aspect of light collection. Separate channels allow:
- Independent calibration of each channel
- Selective reduction of light pollution in individual bands
- Optimization of exposure times for each channel separately
The compact 1.25″ diameter ensures compatibility with most filter wheels and standard accessories.
Key features at a glance
| Feature |
Details |
| Filter diameter |
1.25″ |
| Number of filters |
4 (L, R, G, B) |
| Filter type |
Interference (thin-film coating) |
| Peak transmission |
Typically over 90% at passband center |
| UV and IR blocking |
Yes (luminance and color filters) |
| Compatible cameras |
Monochrome CCD and CMOS cameras |
| Mounting |
Threaded cells |
| Country of manufacture |
Germany |
Why choose Astronomik LRGB filters
The Astronomik 1.25″ LRGB filter set is a reliable foundation for professional color astrophotography with a monochrome camera. German manufacturing precision, verified spectral characteristics, and robust filter construction in threaded cells - all of this makes a tool that will serve you faithfully when photographing galaxies, nebulae, and star clusters for many years to come.
