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Old 03-09-2014, 09:20 PM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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Originally Posted by strongmanmike View Post
Always interesting reading these threads

So to put it simply and apart from taking up less disc space and putting the tracking and unexpected bump/wind/plane/satellite problems etc (which are indeed significant considerations) aside...under what conditions and with what sort of equipment is doing a single 30min sub a significantly better option than doing 6 X 5min subs?

if you have high read noise and low QE, you need longer subs. eg, a system with an 11002 would maybe need 30 minute subs, but an equivalent system (aperture and sampling) with a 694 could possibly only need 5 minute subs, since the 694 has high QE and low read noise. In typical systems, an 11002 would be next to useless with 5 minute subs, but would work fine with 30 minute ones. The main driver is the read noise and the sub length scales with the square of the read noise (all else being equal). If doing narrowband, use subs as long as is practical, regardless of equipment.

Last edited by Shiraz; 03-09-2014 at 09:35 PM.
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