Observing Basics: Filters

Not seeing enough detail on planets? Light pollution getting you down? In each case, the solution may be a small piece of glass.
By | Published: July 23, 2015 | Last updated on May 18, 2023

How much light gets through?
This list show the most common color filters along with the percentage of light they transmit.

0 seconds of 4 minutes, 21 secondsVolume 90%

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Color filter  Transmission (percent) Color filter Transmission (percent)
#3 Light Yellow 88 #32 Magenta 13
#8 Yellow 83 #38A Dark Blue 17
#11 Yellow-Green 40 #44 Light Blue-Green 16
#12 Yellow (minus Blue) 74 #47 Violet 03
#15 Deep Yellow 66 #56 Light Green 53
#16 Yellow-Orange 58 #58 Green 24
#21 Orange 46 #80A Blue 28
#22 Deep Orange 36 #81A Light Orange 82
#23A Light Red 25 #82A Light Blue 73
#25 Red 14 #85 Amber 63

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