Andrew’s Astronomy Blog

With a bright full moon in the sky Dan and I decided to spend the night trying to better understand the society’s 20″ reflector. Getting the best out of it is definitely an art rather than science and the longer you spend with it the better you get to know it’s strange quirks and foibles.

After some time with the Orion nebula I put the webcam on with Televue x2.5 and took some 10fps videos of Saturn. The final one looked the best on the laptop so I stacked 400 of the best frames in Registax and applied a lot of sharpening.

The rings have noticibly opened  since last year and as it climbs higher in the sky it should present a nice target later in the year.

Saturn is back in the evening sky. Having shot some three colour video sequences of Mars on the Celestron 9.25 I switched to Saturn which was just rising out of the murk at about 20 degrees elevation. The rings are just beginning to open out after last year’s edge on aspect and with the planet higher in the sky as it approaches opposition it should be favourable for imaging.

1500 frames each of red, green and blue video were stacked and combined for this image.

Whilst waiting for the sky to darken enough to image M13, I put the webcam on the 9.25 and took a 3 minute video of Saturn against the twilight sky.

I converted the avi file into individual bitmaps using VirtualDub and the then centred the planet in the frame, cropped the image and carried out an initial quality assessment all in one step using Ninox (previously called PPMcentre). Having ordered the frames by quality it is then easy to delete the ones worst affected by atmospheric conditions.

Using Registax, I then stacked the best 300 frames and sharpened the result which is here:

The rings have opened up slightly from their edge-on appearance earlier this year.

After the regular Tuesday meeting of the Imaging Group was somewhat washed out the next clear opportunity was Thursday. This composite picture shows Saturn with 5 of it’s moons at 2100 GMT 1-5-2008.

There’s some photoshop trickery here to replace the very overexposed planet with a correctly exposed one.

From the left, the moons are; Titan, Iapetus (very faint), Rhea, Tethys and Dione.