Details
Description
A good quality set of filters with nice clean glass!
The clear filter has a tiny chip at the edge that will make no difference in use as its within the mount area!
details from web below:
Astrodon Tru-Balance RGB filters have revolutionized CCD imaging. Their popularity is due to ease-of-use, high optical throughput and great resulting color for galaxies, star clusters and nebulae. There are two varieties of Tru-Balance filters - E-Series and I-Series.
I-Series filters are designed to approximately equalize the flux of Kodak's Interline CCD detectors, including compensation for the solar photon flux. This means that your RGB color combine weights will be approximately 1:1:1 within perhaps 10%. This can never be perfect, but it does allow you to take equal time exposures for your RGB data and also just one corresponding dark exposure time.
Introducing Generation 2 True-Balance filters (LRGB2) in April, 2008 in all sizes. This is the first change in Astrodon filter design and fabrication since their inception. We listened to your requests.