Baader CCD Filter Green - 2" - Interference Filter for Astrophotography

Baader Planetarium Green Filter from the RGB CCD Filter Set

This filter is for astrophotographers who want to expose one color channel, in this case the green channel, individually and get the most out of the sky.

The complete filter set would consist of

Interference filter Red (BA2458475R, optional, linked below)

Interference filter Green

Interference filter Blue (BA2458475B, optional, linked below)

General information about Baader CCD filters:

Baader filters are manufactured with the highest precision. Great importance is attached to freedom from reflections and to the accuracy of the surfaces. Each filter is polished to an accuracy of 1/4 Lambda on both sides with Autodeck polishing machines before the filters are subjected to an elaborate coating process. The result is age-resistant filters with the highest accuracy.

Baader´s RGB filters are not just simple color filters, they are special filters with the highest possible light transmission in the respective areas and with the steepest possible edges, so that only the desired light range really gets through. This allows the decisive areas to be photographed with the highest contrast and high quality.

The result is a better color weighting of the image with more intensive contrast - already on the raw image!

The Baader RGB filters are very effective under a light-polluted sky, because a large area of pollution (mercury and sodium vapour lamps) is omitted.

Mechanical properties:

the only filters with homofocally plane-polished substrates. Each individual filter is fine-optically polished to 1/4 wavelength

Baader LRGBC filters are hardcoated separately. The individual filters are not drilled out of large plates as usual.

drilled-out filters show micro cracks at the edge of the coating layer, which tend to absorb moisture due to capillary action

all Baader filters have sealed edges due to individual coating, so moisture penetration is impossible

Baader filters were boiled in water for one hour during long-term ageing tests (for example at B+W Filter/Schneider Kreuznach) and, in contrast to drilled filters, remained completely undamaged.

scratch-resistant hard coatings of Baader filters can be cleaned as often as required - preferably with Baader OpticalWonder cleaning liquid

Optical properties (no reflections in comparison to competing RGB filters):

Balanced RGB design allows images with the same exposure time - extremely important for automated continous imaging

Maximum color contrast for each of the three RGB channels due to extremely steep edges at all transmission curves

[O III] emission line is doubly weighted in the B and G channels, with maximum transmission - for highest deep-sky quantum yield

R-Filter provides maximum transmission and contrast at H-alpha and [S II] but blocks IR from 680 to 1200 nm

Blocking between G and R filters reduces light pollution from mercury and sodium vapor lamps at 580 nm, darkens sky background and improves color balance and separation

The transmission curves of these filters:

Safety informations: PDF Download