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Old 15-01-2007, 09:48 PM
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Satchmo
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Quote:
Originally Posted by bird View Post
Yes, and also you can get the sharpest focus ( red = longest wavelength).
You got me thinking about this one , Anthony.

The difference between an optical wavefront error of say 1/10 wave measured at 633nm and remeasured at 533nm is about 0.025 or 1/40 wave, which couldn't possibly make any difference to a photo. The barlow lens in your sustem is probably optimised for sharpest focus at 533nm . I wonder what is actually at play here to give you a better image with red filter?

Mark
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