Posted by Robin Vann at 00:47 on 2010 Aug 12
Thank you David, that’s reassuring.I’ve also been checking up on the Dawes’ limit. My book (a lunar observing guide) gives it as R = 120 / A where A is aperture in mm and R is in arcseconds. This would appear to give me a Dawes limit of 0.8 arcseconds with my 150mm aperture, assuming seeing being good enough; and for your 5", 0.96 arcseconds, which would also be sufficient to discern them as discs, seeing allowing.I would be interested in your experiments in this regard, and to know what formula you are using for Dawes’ limit.Robin