Astronomik LRGB Filter Set - 50mm Round Unmounted - Type 2c
These filters provide a natural color reproduction of planets, stars, emission- and reflection nebulas. The transmission properties of the L-RGB filters are optimized for CCD astrophotography. The set allows to take images in correct color for all types of objects. Where other brands make strange compromises, we do the best color reproduction possible. Both stars as well as objects that emit only in spectral lines, are reproduced in their true colors. You get CCD images with perfect colors, as if the objects where bright enough to be seen with photopic(?) vision. This feature is the main difference between Astronomik filters an those of other manufacturers.
The following considerations have been very important for the design of Astronomik LRGB filter set:
- simple image processing for the user
- highest transmission (nearly 100%) for short exposure times
- adjusted transmissions of the individual filters for optimal color reproduction
- the use of industry standards
Most importantly, a color correction tool should be provided to astrophotographers that offers a simple and efficient editing process. To maintain the color, Astronomik has calculated their filter set for the sRGB color space, that is used as an industry standard from most manufacturers of monitors, printers and imaging software. As a user you do not need to spend time to learn about colorimetry and color spaces. Astronomik has solved the special problems of astrophotography for you.
Due to the high-precision machining of the carrier substrate, Astronomik filters are parfocal with errors below all usual margins. In order not to be the flaw in a high-quality optical system, Astronomik filters are, of course, diffraction limited. Issues concerning focal distances as well as the exact location of the images of each color image are not a problem at all.
The L-RGB filter set divides the spectrum into its components red, green, blue and luminance. Thus color separation can be achieved with pure b/w CCD sensors. The separation corresponds to the color sensitivity of the human eye according to DIN 5032. By using the sRGB color space it is possible to maintain the color of the image throughout the entire image processing and output. With an Astronomik L-RGB filter set and your camera you create ideal raw material for image processing in the sRGB color space.
Astronomik LRGB Filter Set - 50mm Round (Unmounted) - features:
- Parfocal with other Astronomik filters
- 1mm thick glass
- Completely resistant against high humidity, scratches and aging effects
- Diffraction limited, the filter will not reduce the optical performance of your telescope!
- Astronomik filters are delivered in a high-quality, long lasting, filter box
- The Horizontal axis is the Wavelength in Nanometers (nm).
- 400nm is deep blue,
- at 520nm the human eye senses green and at 600nm red.
- At 656nm is the famous "H-Alpha" emission line of hydrogen.
- The Transmission in % is plotted on the vertical axis. The red line shows the transmission of the filter.
- Visual filters: The grey line in the background shows the relative sensitivity of the human eye at night. The maximum is at ~510nm and drops to longer and shorter wavelengths. You can easily see, that you can´t see anything of the H-alpha line at night (even if you can during daylight!) The sensitivity at 656nm is 0% at night.
- Photographic filters: The grey line in the background shows the sensitivity of a typical CCD sensor.
- The most important artifical emission lines are shown in orange. The artifical light pollution is dominated by Mercury (Hg) and Sodium (Na), which are used in nearly all streetlights.
- The most important emission lines from nebulas are shown in green. The most important lines are from ionized Hydrogen (H-alpha and H-beta) and double ionized Oyxgen (OIII) .
- The major emission lines of artifical light pollution: | Hg 435,8nm | Hg 546,1nm | Hg 577,0nm | Hg 578,1nm | | Na 589,0nm | Na 589,6nm | Na 615,4nm | Na 616,1nm |
- The major emission lines of nebulas: H-β 486,1nm | OIII 495,9nm | OIII 500,7nm | H-α 656,3nm
|Name||Astronomik - LRGB Type 2 Filter Set - 50mm Round Unmounted|