High Point #21 Orange Filter - 2"
This #21 Orange Filter, 46% transmission by High Point Scientific is an invaluable aid to lunar and planetary observing. Colored filters reduce light scattering and glare while increasing contrast via selective filtration. Filters also provide increased definition, reduced irradiation, and lessen eye fatigue. The Orange Filter has a Wratten number of #21 and can help you view the many surface features of Mars. It will reduce the light from blue and green areas, which darkens the maria, oases, and canal markings while lightening desert regions that are orangish in color. When observing Jupiter and Saturn, this filter will help you study features characterized by a bluish hue. With a transmission of 46%, this orange filter is perfect for daytime viewing of Venus and Mercury by darkening the blue sky.
All of High Point's colored filters are made of high quality, solid plane parallel glass that has been anti-reflection coated to prevent glare and ghosting. They have a full 26mm clear aperture and are mounted in a black anodized aluminum cell that is threaded on both sides to fit most 2" eyepieces and stack with each other.
Please note that the effectiveness of this filter depends on several factors, including the aperture and focal length of your telescope, the magnification being used, and the seeing conditions at the time. Remember that filters lower the amount of light that reaches your eye. You'll need an aperture of at least 8 inches for dark filters such as the #47 Violet, with only 3% transmission, the #25 Red with just 14% transmission, or the #38A Blue with 17% transmission.
2" #21 Orange Filter
Dimensions & Specifications
Model Number: 21F2
Filter - Single or Set: Single Filter
Filter Size 50.8 mm (2")
Filter Type: Planetary Color
Filter Shape: Round
Mounted or Unmounted: Mounted
Wratten Number or Equivalent: #21 Orange
Filter Warranty: Two Years
We stand behind all the products we sell, and your satisfaction is our top priority. If you're not satisfied with the quality of your purchase, simply send the item back to us in its original packaging within 30 days of its delivery.
Return & Exchange Policy
At our site, returns are easy! You may return new, unused, and resalable items for a refund or exchange. Simply ensure that the item is returned in its original product packaging within 30 days of delivery.
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