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- Subject: seeing
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- Date: Fri, 22 Aug 97 14:29:47 -0700
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>What you are saying is the optical blur is far worse than the
>blur caused by seeing? Let's assume I have a poor site is this
Yep. The 28 arcsec images (fwhm) are almost all optics-related. A
Spring-time thread decided (I think) that these lenses are poor-fair
in optical quality, and the resolution is about 60 lines/mm. High-quality
lenses (Nikon/Canon) are more like 200 lines/mm, which would give sub-pixel
resolution, but are 10-100x more costly.
The worst seeing I've ever tried to observe through was about 10arcsec.
It takes a really, really bad site to have typical seeing that bad. Most
lowland amateur sites are in the 3-5arcsec range. All of these figures are
far below the 28arcsec TASS images, which is why I say we are essentially
in the pre-fix HST era, and should be able to model the aberrations in an
analytic fashion pretty well.