In April 2008 some days before leaving for my astroimaging trip to Namibia I received the new CLRGB filter set from Baader, all in 50.6 mm round design for my STL camera. To the right you see the filters inserted into the big |
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Here you see the transmission curve from the RGB set (origin Baader). They are showing steep rise on both ends, the blue and green filters both utilize the O-III wavelenght to full extend. |
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Other than with my previous filters the new set allows an 1:1:1 frame weighting for RGB combine what makes collecting of RGB frames easy with equal exposure time. To the right you see the result of a straight RGB conbine at 1:1:1 on the well know target M20 using my STL-11000 camera. This object is a tough one when trying to separate the 5 central bright multiple stars. Follow the link to see the result of combining just 10 min raw frames without using shorter exposures. |
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Here you see a straight 1 sec RGB exposure on Sirius with the 20" cassegrain at IAS/Hakos in corrected secondary focus, weighted 1:1:1, rescaled to 200% size and displayed in linear mode. Without intention this test shot revealed the faint Sirius B companion, 10 magnitudes dimmer than Sirius A. It is partly hidden by the spike, the distance A-B measured at 8" as well as the position angle correspond with the chart from the literature. |
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Here you see the transmission curve from the Luminance filter (origin Baader). |
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Here you see the transmission curve from the Clear filter (origin Baader). |
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The L and C filter are free from any reflections on bright stars see the image to the right displaying a 1 sec exposure of Sirius with the 20" at f/9 in 25/50% size log stretched
Download the original fits files for all 5 filters (cropped, 2x2 bin): here |
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