Thread: F-ratio myth
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Old 20-02-2018, 08:56 PM
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RickS (Rick)
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Well, aperture is half the story, Peter. The other half is image scale, combining focal length and pixel size. A small aperture scope can be faster than a huge aperture provided you're collecting the photons in big enough buckets (and are happy with much less resolution with a larger FOV as the upside.)

I do agree that the f-ratio of a scope is meaningless by itself...

Cheers,
Rick.
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