Thursday, 23 July 2009

Found the Andromeda galaxy using the new kit last night.

In the couple of clearish hours last night between clouds, I set up the 'scope with the new finder and wide-angle eyepiece (a Baader Hyperion Aspheric 31mm). The finder is great. So much easier than using the straight-through finder-scope. It projects a pair of concentric circles up to the viewer which, due to some clever optics, remains steady relative to the stars regardless of how you move your head. I didn't bother with the finder-scope at all last night so the scope wasn't too top heavy.

The first thing I did was point towards cygnus's rear end, to drink in the multitude of stars in the milky way. Pretty awesome in the 1.8 degree field of view and a mere 40x magnifiation.

Next I thought I'd find the Andromeda Galaxy. It wasn't hard to find, once I'd worked out how huge the Andromeda constellation is. The core was nicely visible as were two companion galaxies, all in the field of view at once. Despite the light sky, it was possible to see the orientation of the disc, a hazy elongated ellipse stretching out of view either way. Nice.

Posted via email from Graham's posterous

Wednesday, 15 July 2009

Found the Dumbbell Nebula

Just come in from a moonless and surprisingly clear sky. Found the Dumbbell Nebula (M27), which was bigger that I was expecting. Couldn't see any detail, just a hazy blob with a slightly darker band round its middle. Could see stars through it, or in front of it. Also found a little cluster nearby. Not sure what it was. Pleased my star-hopping is getting better, but I need another finder to complement the straight scope.

Jupiter was looking very neatly flanked by a pair of moons either side of it. The atmosphere was quite stable, so I could use highest magnification (about 300x currently) and really get a good look at the banding.

Posted via email from Graham's posterous

Sunday, 5 July 2009

Created a pathetic image of jupiter too

Jupiter is that tiny striped blob! So this is my first real attempt at using RegiStax to combine more than one frame in an image. Given the raw material, it's done a reasonable job. It was pretty hazy and the moon was almost full too. Jupiter's moons are too dim to be seen in theis shot (apparently Io was in transit during the exposure.)

Posted via email from Graham's posterous

First webcam image through telescope: the moon in bad skies.

Last night I reconfigured (cobbled) a webcam to hook up to the 10" dobsonian. All I had to do was remove the lens and then find some way of fixing it in place of the eyepeice. Turns out a sligtly modified 35mm film case works well. Amazingly, the focal plane lay well within the normal range of the focusser, so things were pretty straight-forward and stable. The only issue is that the CCD in the webcam is tiny, so the images are very zoomed.

Features on the surface stay in the field of view for about 45 seconds. The earth rotates at 360 degs/24 hours => 1/4 degee per minute. This makes the FOV is about 0.2 degrees, pretty narrow. With the barlow, I can only make that narrower.

Being a rubbish old webcam, literally from a skip, it is only 640 x 480. Am now playing with the awesome-looking RegiStax to see if multiple images will get better quality.

Posted via email from Graham's posterous

Saturday, 4 July 2009

Last night's tally

Had surprisingly good skies last night and Jupiter was very clear, managed to see four moons and very clear colour banding. Also found the ring nebula and M13 again, as well as M92. The new 8mm eyepeice was really good. Clear and a good field of view, seeing individual stars in the globular clusters was easy. It also woked really well in the 2x barlow to give 300x magnification, whcih was very useful for jupiter. I definintly need to improve my star-hopping though, spent too long trying to find stuff, and not enough time looking :)

Posted via email from Graham's posterous