On Sat, Nov 7, 2020 at 8:06 AM Fr¨¦d¨¦ric Ruciak <frederic.ruciak@...> wrote:
Hi everyone, hope you do well, yesterday night, having a chance to observe Mars with my classic 15, on a rather stable night, I had a very interesting experience. At first with full aperture, I had a very luminous image dancing a little bit on the edge with very luminous diffraction rays (rather large due to the planet being rather large too). I tried to close the aperture with a mask letting only a circular aperture decentered to be completely free on any obstruction. As you can imagine the diameter is around 6 inches (15-20%)/2. The scope became a 6 inches f 9 more or less 0% obstruction. I was observing with a ethos 8mm at x250 well beyond the theoritical ~300 limit for a 6 inches scope. The image became much darker (4 times less light incoming) but much easier to observe because of no diffraction rays at all and I have been able to spot more details and some very luminous spot at the pole of Mars most probably the very last remnant of the polar cap. I never had this kind of improvement before especially when observing planets like Jupiter or Saturn, I always preferred the full aperture view. Any comments of similar experience? Clear skies, Fr¨¦d¨¦ric