Re: Much better observation of Mars with a mask on my classic 15
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Dave's probably already started designing the 28.
On Saturday, November 7, 2020, 9:06:12 AM MST, Roger Greenwood <roger@...> wrote:
Correction!!!!
18" Classic...
On Nov 7, 2020, at 11:05 AM, Roger Greenwood via groups.io <roger@...> wrote:
?
I will definitely try this with my 28" Classic!!
-Roger
18" Classic AN/SC/FSA
On Nov 7, 2020, at 9:06 AM, Fr¨¦d¨¦ric Ruciak via groups.io <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
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