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Post Info TOPIC: Wratten #21 Filter


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Wratten #21 Filter

Antares #21 Orange Filter 1.25"

46% transmission

Reduces transmission of blue and green wavelengths. blocks visible wavelengths below 530nm. Useful on Mars for Maria and sharpen the bounderies between yellow/orange areas and blue-green regions. Enhances cloud belts and Polar Regions on Jupiter and Saturn and is very effective at bringing out the Great Red Spot. On Saturn it performs much like a #15 amber filter but delivering higher contrast. Can also be used to reduce the glare of Venus and darken a twilit sky.

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