Monday, December 24, 2007

Mars 2007 opposition, second image

My second attempt for Mars imaging was near to 2007 opposition at 22nd December. Last time I did not succeed on imaging with my Barlow lens. Now I was able to get decent sized planet on the webcam sensor. There were not so many details on the side of Mars I have photographed, so more attempts are needed. I tried to focus as cafully as I could, with WO SCT focuser. There was no sharp focus point present. This may have been due to seeing effects. I had to battle a lot during imaging, to avaoid frost formation on the corrector lens. Good point to continue for next imaging round. Equiment used: Celestron C8 XLT, Televue 3x Barlow, SPC900NC. Image capturing and processing: VirtualDub, Registax v4 and Photoshop CS2.

Mars 2007 opposition, first light

Long time (over two weeks :-) after I got my C8 package, skies were finally clearing at Espoo. On the early morning hours of 13th December 2007, I carried my (damn heavy) equipment to near hill. First I did some visual tests of my scope, then finally pointed C8 to Mars. I got couple of raw video sequences. The planet size on the webcam sensor was way too small. Still some small details were revealed. I tried also to attach 3x Barlow lens, but I did not got video captured because of focusing problems (WO SCT focuser worked OK).

Thursday, December 6, 2007

SC OTA for planets, thoughts

Since the weather doesn't allow planet photography, I have plenty of time to consider what I need to invest in the near future to my C8 package:
  • Dew shield
Needed especially in cold winter nights. Normally the corrector lens will suffer from frost formation, just when the imaging session is ongoing... Flexible model would be more convenient, since my setup needs to be portable.
  • Magnifying finder
There was only a red dot finder (RDF) include in C8 (without base..., that was promised to be separately sent to me). Brightest planets will be visible through an RDF, but it may be a bit struggling to get planet directly in the field of small webcam sensor. This remains to be seen with the actual use of scope.
  • Heater strips
Combined with dewshield, heater strips will be another (and propably the best) solution to battle against corrector lens frost. If/when I get more seriously interested about visual use of my scope, I may need to buy heater strip for eyepieces also.

Tuesday, December 4, 2007

SC OTA for planets, scope arrived

The C8 XLT scope arrived, at 30th November 2007. I wasn't home, when first delivery was attempted by UPS, so scope had to picked up at local UPS storage premises. This is how my planet imaging setup looks like:

System consists of Celestron C8 XLT Schmidt-Cassegrain scope (2032mm, f/10), mounted on Skywatcher HEQ-5. There is enough of focal length in C8 to be used for planet imaging. In case I later on get interested in DS photography, this tube will come in handy with some focal reducer - like 0.5x -model from Optec.

I have bought a separate Grayford focuser from William Optics. This way you can get a smoother focusing, and also both 1.25" and 2" accessory connections. Focuser also rotates around it's axis, to allow suitable composition in the image.

3X barlox is from Televue, quality and build looks and feels very convincing. Barlow lens felt solid, and a bit heavy when I first took it in my hand. I believe it will be worth of invesment. Reflections in the lens surfaces were very deep green, so I assume lens coatings are typical (and good) Televue value.

AVI sequence of the planets will be captured with Philips web camera. SPC900NC was available at the time. Oririginal lens was removed from camera and 1.25" adapter was screwed into lens thread. I also use a Baader UV/IR cut filter in front of the sensor, to ensure better image quality.

All I need now is some freetime and clear skies with good seeing. Currently it does not look too promising... Sleet is pouring down from the sky.