I'd spent much of the day fussing about how to get the polarscope
calibrated and working, so it was ironic that when I set the mount up
I couldn't even see Polaris, even through binoculars. Saturn was
visible however, so I guessed where the North Celestial Pole was, and
mounted the counterweights and tube.

I hadn't even calibrated the spotter scope, but with Saturn centred,
and a 25mm eyepiece (EP) fitted, Saturn was quite close to the middle
of the view. And it was absolutely spectacular! Though the
magnification was only 48x compared to the 56x that I was using
through my 2.5" refractor the other night, the view was so much
superior, and of course more stable thanks to the better mount, that
it was highly unexpected.

Saturn through the 25mm was extremely bright, and the rings protruded
out to the sides very clearly. I decided to try the 10mm right away,
and that was even better with no loss of quality in the brightness.
Then I thought I'd try the maximum magnification combination I
currently have at my disposal, and put the 2x barlow on with the 10mm
lens. Saturn was huge, the 240x magnification being far more than I'm
used to, but it was still extremely bright and the contrast didn't
seem too bad either. As well as the rings I could also see the ring
shadow across Saturn.

What was most surprising is that I could see Saturn's moons. This is
probably one of those things that is utterly taken for granted by most
amateur astronomers with any experience at all, but to me it was
unexpected to see a combination not only of the rings of Saturn but
also what I'm more accustomed to from Jupiter. Everybody talks about
the Galilean moons, but not so much Titan and the Cassinian moons.

Rhea and Titan were clearly visible to the right, through the inverted
image, and then with the 10mm and 2x barlow you could just make out
Tethys to the left. Even the starform lens aberration was pretty, the
whole thing looking much better than anything I'd seen online. There's
something very strange about seeing such scenes through a telescope,
because on one hand they look so strange as to be almost unrealistic,
but the detail is so superb and the wind wobbling the scope and
turbulence occasionally making it blurry makes it so immediate.

I also tried to find Bode's Galaxy, which I'd located easily through
binoculars yesterday evening, but got extremely lost thanks to the
different zoom level and the inversion of the image. It was also quite
uncomfortable looking through the spotter scope pointing essentially
straight up. Then I set the scope more uphill and pointed it to Mars,
which to be honest was too bright to look good. The disc was
discernible, but detail was not, so I think I need a red filter for
it. It was at that point starting to get cloudy anyway, but it was
also around 10pm, so the cloud had thankfully held off pretty well.

Then I looked at Saturn again through the 25mm EP, and took some
photographs of the telescope. Since the 10mm and 2x barlow worked so
well, with very bright and clear views of Saturn still, I've just
bought a 7.5mm Plössl as well. This should give a maximum
magnification of 320x, which is just outside the range that's expected
to be useful with this telescope, though I suspect it'll be just fine.

I have a motor drive for the mount, especially for astrophotography,
but I haven't even got that out of the box completely yet. I'd like to
take some good photographs of Saturn, so I'd definitely need to do
better polarscopic alignment, and to make sure that the motor is set
up correctly. It wasn't too bad controlling the R.A. myself, and given
that I barely needed to touch the Dec control except when I was being
really fussy I think my guess of the NCP was pretty good. But of
course for astrophotography a motor is essential, especially through
the higher magnifications.

Background reading:

http://groups.google.com/group/whits/t/a98b41f51ad84da8
Bode's Galaxy, 12th April

http://groups.google.com/group/whits/t/ec086002de24024d
Saturn's Rings, 11th April

http://groups.google.com/group/whits/t/6ee23be37dccf25a
Photographing Saturn, 3rd April

On 13 April 2010 23:40, Sean B. Palmer <s...@miscoranda.com> wrote:
> Today my new telescope arrived, and BBC Weather said that cloud was
> coming in at 9pm.

Sods law working nicely!
Any detail on this glass combo Sean please? Not something I've even
looked at(through?) before, you make it sound quite intriguing.

regards

--
Dave Pawson
XSLT XSL-FO FAQ.
Docbook FAQ.
http://www.dpawson.co.uk

On Wed, Apr 14, 2010 at 8:19 AM, Dave Pawson wrote:

> Any detail on this glass combo Sean please?

The telescope is a 6" (150mm) parabolic newtonian reflector, and the
EPs are probably modified achromats according to the supplier. My old
telescope had mainly Huygens lenses, which are of the worst possible
design. The extra lens that I bought overnight is a cheap Plössl,
which is now the most popular type and hopefully a small step up from
the cheap achromats.

http://en.wikipedia.org/wiki/Eyepiece#Eyepiece_designs

At this sort of level I don't think the EPs matter too much. Even
moderate EPs can cost just as much as the telescope itself. The
aperture and the stability of the mount at an affordable price were
the two main things that I was aiming at.

The mount that I got is of an equatorial type. Though it's very well
made and feels sturdy, it did seem a bit wobbly yesterday evening in
the slight breeze. I didn't spend much time setting up the balance,
though, so that may have contributed to the problem, and it wasn't too
bad.

I was very impressed with the controls: moving the telescope around in
big movements is relatively easy, and in small movements very easy.
The equatorial nature of the mount means you just have to give the
R.A. control a slight anti-clockwise tweak now and then to follow an
object, which is great.

Thanks Sean. Appreciated.

On 14 April 2010 12:39, Sean B. Palmer <s...@miscoranda.com> wrote:
> On Wed, Apr 14, 2010 at 8:19 AM, Dave Pawson wrote:
>
>> Any detail on this glass combo Sean please?
>

--
Dave Pawson
XSLT XSL-FO FAQ.
Docbook FAQ.
http://www.dpawson.co.uk

On Wed, Apr 14, 2010 at 11:59 PM, Pedro Ferreira wrote:

> Thanks a lot for this account, it brought back some old passions :).

Just a week ago I was in the same position as you are now, very
interested in astronomy when I was younger but never had anything more
than a refracting telescope. When I got a new camera unexpectedly this
year, I thought it would be nice to try to take a photograph of
Saturn, and that's managed to bloom into a new obsession with
astronomy.

One of the mistakes that I made was thinking that buying a telescope
is never going to match the spectacular Hubble telescope views and so
on that you get online. And why bother scanning the stars with
binoculars when you can learn them all from star charts? Now that I've
bought a proper telescope, I've got no idea why I didn't do it sooner!

Without the motor, this absolutely enormous telescope cost only as
much as my old compact digital camera, so really I didn't have any
excuse. I'm not saying that everybody should go out and randomly buy a
huge telescope, because certainly there's a heck of a lot of research
and effort and frustration (equipment choices, cloudy nights, etc.)
involved. But I thoroughly recommend thinking about it.

The strangest thing about it really is just how much different looking
through a telescope is to looking at something online. I've looked
through big telescopes before, but never for very long before it was
somebody else's turn. To actually stand for twenty minutes watching
Saturn sailing through the skies with its moons is really something.

And it's not just that, it's the whole process in a way. You look at
what telescope you need, and along the way you learn tons about how
telescopes work and the history of them and all the different opinions
that the enthusiasts have of them. You learn about aperture and focal
length, and eyepiece types and equatorial mounts, different
calibration steps involved, collimation, chromatic aberration, and so
on, but all mainly in passing through mentions on forums and in
advertising spiel.

Then you buy a telescope, you spend hours setting it up and hoping it
won't be cloudy, and you go out and assemble yourself. Having gone
through the whole process, you then look through it for the first
time. What I did was to point it immediately at Saturn without even
having calibrated the spotter scope. I took the massive lens cap off,
it's as big as a dinner plate, and put it on the tripod tray. And I
looked through, saw some blurry white dots, tweaked the focus adjustor
and *there was Saturn right there, looking amazing.* It was so
gratifying to have done all that research, all of that preparation,
and to get instant results like that!

Today I got my cheap Plössl EP, and I found out that my t-ring screws
successfully onto the barlow lens, so I don't need to purchase a
t-adaptor. I'm wondering if ash from the Eyjafjallajökul eruption is
going to make any impact on viewing conditions in the UK.