Saturday was a clear night to try out the new lenses that were delivered earlier this week from OVL. Probably one of the best nights so far for getting my telescope out, I set it up in the back garden and as Cassiopeia was high in the sky, decided to hunt for my first object; the Andromeda galaxy, M31.
Having studied my Philips ‘Guide to the Northern Skies’, I had arough idea of the patch of sky where it could be found. Deciding to use the smallest magnification lens in my new kit (the 20mm) to help me have a good chance of being able to pan around the sky and chance upon the object.
Surprisingly enought, it didn’t take me that long to happen upon a faint, fuzzy grey blob. Changing down to the 15mm lens and re-centering the ‘scope, then again to the 5mm lens, the problems of light pollution and living near a big city became apparent. The most resolution I could make out was simply a larger version of the fuzzy blob I spied earlier. The 2mm lens was even worse and I changed back to the 5mm. Satisfied this was the best view I was going to get, I turned the scope around to target Jupiter, which was just coming into view from behind the trees.
This is where is started to get a few problems. I noticed that even though I had a clear aim and lined up the red dot scope direct on Jupiter, the view through through the lens was of the trees a short distance away. Having spent about 15 minutes moving the scope, fiddling with the red dot finder and getting a little exasperated not getting Jupiter in view, I decided that I must have moved one of the adjustment dials on the red dot finder so I simply started to move the RA/Dec dials until I came across Jupiter by chance. Sure enough it came into view and I started to change the lenses so I could get a better view of Jupiter and the Galilean moons.
Changing to the 2mm lens, I came across something that I’d read about in the Astronomy books; ‘poor seeing’, ie. poor focusing due to atmospheric effects. No matter how much I tried to focus, the image of Jupiter continued to ‘wobble’ and be indistinct.
This is caused by heat/turbulence in the atmosphere and makes focussing on the object downright impossible. There isn’t a lot you can do about it so I changed back to a 5mm lens to get back a sharper view.
I did get to try out the filters before I packed up, but I’ll save my findings for my next post.
Posted by Wordmobi