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Old 16-08-2019, 08:06 AM
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The_bluester (Paul)
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The_bluester is offline
Join Date: Feb 2011
Location: Kilmore, Australia
Posts: 2,686
Celestron RASA 8 users

Anyone on the forum got their hands on one of these yet? I keep seeing the appeal of F2 imaging (Where my 5 minute subs at F4.9 would be more like 1 minute at F2) but the scope obviously has some designed in limitations. I have seen them described all the way up to being "Issues" or even flaws or defects, but to me they seem to just be design compromises and no matter what the configuration every telescope has compromises in one area or another.

My work usually produces a nice little annual bonus around March and in recent years a chunk of that has gone in to astro gear so I am looking ahead to next year.

At this point there are only a handful of images on the likes of Astrobin identified as being from an 8" RASA and they span the expected spectrum from pretty flash to pretty ordinary. I was hoping a member on here might have some insight on the real world performance of these scopes with their intended OSC camera configuration. They look like they could have been practically designed with my ASI294MC Pro in mind.

Another question is filters. I know for NB filters they need to have specifically designed filters for best results with the steep light cone at F2, but does that apply to a UV-IR filter? A handful of nm shift in the band pass at either end of a filter spanning around 400 to 700nm passband is not going to make much difference where a couple of NM shift on a 3 or 4nm notch filter is obviously going to change it's outcome significantly. I ask that as the 294 at least on my little ED72 benefited insanely from a UV-IR filter and examining subs from the SCT most of the same artifacts that were on the refractor images are visible there, so it seems likely to be a required filter in more than just a "cheap frac" configuration. The only image I have found that specifically couples the same camera as I have with a RASA 8" shows promise, but has a way to go and seems to me to show some of the filter-less issues I see with my ED72, I also have no idea about the users experience, how their night of data capture went and anything about their workflow on processing.

Anyone with any real world experience of these scopes on the forum?
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