View Single Post
  #16   Report Post  
Old May 13th 10, 07:39 PM posted to rec.radio.shortwave
Mark S. Holden Mark S. Holden is offline
external usenet poster
 
First recorded activity by RadioBanter: Jun 2006
Posts: 32
Default Chesterfield Island

D. Peter Maus wrote:
On 5/12/10 09:51 , bpnjensen wrote:

In amateur astronomy, we have two kinds of observers -

Those who use a PC "go-to" to find and locate every faint galaxy
to look at - and then sometimes they can see it and sometimes
not, because they do not train themselves to hunt and then locate
and observe; and

Those who do it the old fashioned way by using star charts and
the Mark I eyeball method - and then usually they see it. It
takes longer, but we usually bag our quarry, and the reward
tastes just a bit sweeter...

I am not sure if this applies to what you're doing or not - but
I surely enjoy the hunt and identification.

Bruce




Funny you should mention this....The NexStar by Celestron all have
computerized motor drives that locate from a database with a couple
of button presses. I was looking at the new scopes with my g/f (who is
also a stargazer), recently, and she said, "doesn't this depend on
whether the mount is set up correctly?"

Why, yes. Yes, it does.

Further, it takes exactly the same skills, and knowledge to set up
the mount as it does to hunt the sky using charts and a timepiece.

When I set up my C8 (Starbright) in the deep weeds, away from
urban light pollution, there is, indeed, a sense of discovery, and
capture, when I find a deep sky object using simple math, and basic
charts. More importantly, and this applies to a lot of technology
driven activities, today, when the technology fails, no matter the
reason, I can still soldier on, having fun getting it done, with no
more difficulty than simply opening a chart.


It depends what you want to do.

I think virtually all of the mounts designed for imaging include goto
these days because some of the targets we image are too faint to be seen
in real time with a transportable scope. It's not uncommon for me to
need to take a couple 10-20 second exposures just to compose my frame.

While some goto scopes are not critical on polar alignment, (in fact
many of them are alt-az instead of equatorial) the Astro-Physics ones
pretty much demand you have a reasonably good polar alignment, because
if you just do a multiple star sync and have the mount calculate things
out you'll end up with field rotation if you're imaging.

An incredible advantage to goto is for public outreach. It's not fun
hunting down an elusive target if you've got a couple dozen people
standing around waiting. With goto, after everyone has looked, I can
punch a few buttons and while the scope slews to the object I can tell
them about the next object we'll be looking at.

The Dobsonian mount was a wonderful invention because it made useful
scopes affordable and larger portable scopes possible, but even John
Dobson tells people it has it's limitations. Haven't seen him in a
couple years, but before he had a stroke, he was a regular visitor to
the North East, and I'd usually run into him a few times a year. Last
time he was out he helped a kid make a transportable 10" f8 dob with a
mirror I got from North American Rockwell. It's a beast to use as
things drift out of the field quickly, but the optics are incredible.

And to include some closer to on topic content - has anyone here
experimented with using a slinky as a loading coil for a "portable"
vertical antenna? If so, any thoughts on if it's worthwhile?