bob

i viewed the moon today superb quality

but when i viewed saturn could not get sharpe image on any lens
i was like the telescope was jittering( shaking )

tried indoors and out

still the same

any helpfull ideas
thanks
bob

Hi Bob

The Moon is a large object and even when magnified it is not difficult
to keep it in the field of view. You won't see it as sharply as it
might be if it's shaking about. But you can still see a lot of detail.

Saturn is relatively tiny even at 120-150x and will dance all over the
place in the field of view.

Which telescope were you using and how was it supported?
On a proper astronomical telescope mounting? A tripod with pan and
tilt head or even a ball and socket head?

Or leaning on top of the garden fence or window sill? Don't laugh. Most
of us have done it. You should try it with a 5" f/15 refractor over six
feet long! An exercise in frustration even on the Moon. :-)

Chris.B

bob

ive got a celestron powerseeker
equatorial mount,, focal length 900
tried 20mm lens 45x mag
and then with 3x barlows =135 x mag
all jittery
there was a slit breeze but even in doors with patio doors open
could not get sharpe image......

a few weeks back, viewed it superbly out garden ( no moon in sky )
just wondered why tonight, why couldnt get sharpe image...


thanks for reply
cant fault ya bob

If you were looking out through patio doors the warm air from indoors
would be mixing with the cold air outside.
Just like looking though the hot air coming off the top of a bonfire.
You'll just have to wrap up well and try again outside I'm afraid.
You can't get a really sharp picture through glass doors either.
You don't need to worry about the Moon. Saturn is bright enough to see
even beside a full moon.

Chris.B

donal

I had the same problem.

It turns out that I can't get a steady image when I try to view anything
above the neighbours houses. The rising heat makes the image "wobble".


Regards


Donal
--

bob

would of never thought of that
heat rising,,,,
will try tonight if conditions allow
cheers
bob

robin leadbeater

Hi Bob,

Even outside you will find everything will be sharp and clear one day and
wobbly and fuzzy the next due to changes in the stability of the atmosphere.
(seeing) It will help if you view Saturn when it is at its highest in the
sky. (less atmosphere to look through) Also don't forget to let your
telsecope cool down. It will take at least half an hour to get the best
image if you take it outside from a warm house.

Robin
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Robin Leadbeater
54.75N 3.24W
http://www.leadbeaterhome.fsnet.co.uk/astro.htm
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pete lawrence

Makes all of the difference bob. Another thing to look out for is how
the stars are twinkling. If bright stars seem to be flickering a lot
then the chances are that the atmospheric seeing isn't very good.
Under such circumstances, a view of Saturn is likely to be
disappointing too.

The general guidelines for good steady views are:

Don't observer from indoors or even near the house if you can avoid
it.
Don't observer above heat sources (these can be houses, towns or even
neighbours bonfires!).
Keep an eye on the seeing conditions. The less flicker in a bright
star (don't use Saturn as a guide - use a bright star) then the better
the seeing conditions are likely to be.
Let your telescope cool down beforehand. A reflector or SCT will
require more time to cool down than a refractor. A general rule of
thumb here would be to aim to get the scope outside for 1 or 2 hours
prior to your observing session. Of course, if it's damp, this can
lead to the scope dewing up before you actually get to use it ;-)
Don't stand there with a hot cuppa in your hand so that as you look
through the eyepiece, the heat from the drink is rising in front of
the scope!
Keep the magnification low at first and work it up to the highest
power that the seeing conditions will stand. Good seeing is not as
common as bad seeing!
Mist or thin fog can actually improve the view of a planet (as long as
it doesn't reduce the light levels too much.

I'm sure I've missed some, but these will put you on the right track.

--
Pete
http://www.digitalsky.org.uk

bob

very good advice
thank you all
suprising things
that make
a difference
used to keep my scope in a warm bedroom
will now keep it in the colder conservaory
thanks
guys