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Originally Posted by Zaps
This reminds me of the arguments of the Astro-Physics fanatics back home. For them it was Astro-Physics or nothing, no matter how much logic and reason was proffered. Yet I have to think that if Astro-Physics wasn't an American company, those same fanatics would have no interest in it.
At least 99% of their stance was based on patriotism and flag waving. Most of them never let their precious telescopes leave their den or dining room anyway. That is if they hadn't already sold it and made a profit before it was delivered to them.
For the record, in my opinion, there aren't many $12000 telescopes that are $8000 better than a $4000 telescope. There may be none that are $8000 better. Looks like some people don't think an $8000 brand sticker is overpriced, I guess.
But speaking for myself, I'd happily save that money and buy a "junky Chinese made clone", then slap a few upgrades on it. The end result is a telescope which performs as well as a dining room display model but for a lot less cost.
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Since you want to bash AP I'll provide you with a few words from Roland to ponder, and ask why exactly are these chinese made RC scopes popular? Is it because of the performance, or is it simply because everyone see's expensive RC's and want these chinese made ones simply because they are relatively cheap?
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What we tend to have in the astronomy world is a bunch of little mini-revolutions. It used to be that one got either a long focus achromat or a Newtonian of longish focal ratio. That was normal some 40 - 50 years ago. Then along came Celestron, and the whole ballgame changed. These scopes were compact and user friendly, with enough aperture to make things interesting. Then came Dobson, who said bigger is better, so everyone jumped on that bandwagon. Then along came the apo refractor, which promised a refined image and good astrophotography potential in a smaller aperture. These kind of co-existed and were developed to more and more exacting standards. Then came the large RC imaging scopes when the CCD camera displaced film. Now we are in the era of Chinese cloning of all these types at a low cost level, but not yet advancing the state of the art.
You ask whether any other scope type exists that can achive almost perfect performance for $1400. Yes, I believe such a scope is possible to make. If I were to decide to wade into this area, I would go back to basics to design such an instrument, and it would not be a Cassegrain. I would start with a basic medium fast parabolic mirror, maybe 8" F5 or F6, add a simple 2 element coma corrector. Both optics are fairly easy to make, and the primary mirror can be produced to a fairly high level of accuracy (the coma corrector does not need fancy corrections). A smallish secondary obstruction of around 35% should be able to cover most CCD chips, and produce a nice flat coma-free field. Of course one could go nuts and make it super fast, but then the cost goes up.
Why is such a thing not made today? Probably because large expensive RCs are being used by advanced imagers to produce some really incredible images, thus these scopes are hot! So the world of marketeering is simply using this hotness to promote a smaller, more affordable instrument. Why not a similar Newtonian with dedicated coma corrector/flattener? Because it's not as sexy sounding as an RC, it's not hot. Why are large scopes RCs instead of cheaper to make Newtonians? Because they are lighter and shorter and require less mounting brute force than a large Newtonian. So, round and round we go. We love the large RCs, but can't afford them, so we lust over one that is affordable. But it may not be the best choice for a low cost very high performance imaging system.
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