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Old 18-05-2016, 11:56 AM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
Posts: 4,918
short subs - better resolution?

OK, this is what I measured. Left chart shows the first night where I just did a sequence of subs from 5 minutes down to 1 second (with a handful of subs at the shorter settings so that they could be averaged). The second try was more ambitious, with more subs of various lengths taken in sequence, but with the sequence repeated 4 times to ensure that resolution changes were not just due to slowly improving seeing. Focusing was redone regularly, but not synchronised with the sub length sequence (ie, there was no focus bias in favour of any sub length). Same result both nights - shorter subs are sharper as measured by the PI image grading script (also hand checked a few subs with essentially similar results).

Now to try to work out what the mechanism might be!!!

regards Ray

edit: am guiding from well outside of the isokinetic patch, and am beginning to suspect that might be behind this result.
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Last edited by Shiraz; 26-05-2016 at 08:20 AM.
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