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DSO Telescope Viewing Sizes

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#26 Tony Flanders

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Posted 11 January 2013 - 03:06 PM

I'm looking at the spectrum of apertures that are available to today's amateurs, not ease of use or other factors. At most any major star party, an 18" truss-tube Dob hardly draws any attention any more ...


True. However, star-party attendees aren't necessarily typical of amateur astronomers in general. When writing an observing article for the broader public, I feel safe in calling a 16-inch scope big.

Also, when discussing what's visible in various size scopes, it doesn't make sense to tune it by telescope type. Six inches is still way above average for refractor apertures, but a 6-inch refractor doesn't show any more than an 8-inch Newtonian. So it still counts as medium-sized for this purposes.

#27 Jon Isaacs

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Posted 11 January 2013 - 06:29 PM

I'm looking at the spectrum of apertures that are available to today's amateurs, not ease of use or other factors. At most any major star party, an 18" truss-tube Dob hardly draws any attention any more ...


True. However, star-party attendees aren't necessarily typical of amateur astronomers in general. When writing an observing article for the broader public, I feel safe in calling a 16-inch scope big.


I am comfortable calling a 12.5 inch scope big/large. With dark skies, with a skilled observer, a 12 inch class scope can take you a long ways.

At a star party an 20 inch or 25 inch might be common place but that star party might be the only time during the year that the scope actually sees the night sky. People show their equipment at star parties but it is likely they do not have the opportunity to use a such a large scope at home. If I am like most other owners of larger telescopes, and a informal internet survey several years ago agreed with me, most have scopes that are more manageable that get more use. I am fortunate in that regard because I have a place to keep my larger scopes where the skies are reasonably dark but I still use the 12.5 inch and the 16 inch more than the 25 inch.

The purpose of this thread is help novices understand the ranking system used by authors when they discuss what is possible with small, medium and large scopes.. In that context, Tony is the one with the most experience. When I read such lists, generally it seems to me, the objects reserved for large scopes can be observed with a 12.5 inch if the conditions are favorable.

Jon

#28 Dave Mitsky

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Posted 12 January 2013 - 12:51 AM

Jon,

That is not my experience at all. I regularly go observing with fellow astronomy club members who own 18, 20, 22, 24, and 25-inch Dobs. By regularly, I mean at least several times a month, if the weather gods permit.

http://www.cloudynig...5564427/page...

Frequency of use or what can be seen with one aperture or another are rather besides the point of what large means in the context of today's reality.

We're going to have to agree to disagree.

Dave Mitsky

#29 Tony Flanders

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Posted 12 January 2013 - 05:35 AM

At a star party an 20 inch or 25 inch might be common place but that star party might be the only time during the year that the scope actually sees the night sky. People show their equipment at star parties but it is likely they do not have the opportunity to use a such a large scope at home.


I'm inclined to agree with David Mitsky on this one. I know a fair number of people with scopes in this size range, and all of them use them regularly. I find it hard to imagine anybody splashing out that kind of money for a scope that's only used at star parties.

But just as people who attend star parties aren't necessarily typical, the people that I know aren't necessarily typical.

#30 Jon Isaacs

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Posted 12 January 2013 - 08:05 AM

At a star party an 20 inch or 25 inch might be common place but that star party might be the only time during the year that the scope actually sees the night sky. People show their equipment at star parties but it is likely they do not have the opportunity to use a such a large scope at home.


I'm inclined to agree with David Mitsky on this one. I know a fair number of people with scopes in this size range, and all of them use them regularly. I find it hard to imagine anybody splashing out that kind of money for a scope that's only used at star parties.

But just as people who attend star parties aren't necessarily typical, the people that I know aren't necessarily typical.


Indeed. I can speak best of my experience as an owner of some larger telescopes. In my situation, I typically get out to dark skies for 6 nights, maybe 8 in a good month, in a bad month, it may only be 2 or 3 times, I will almost always be observing with either the 16 inch or the 25 inch.

But home is where I do most of my observing, at least by nights if not by hours, and here I use something smaller.

Jon






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