3/6/03 Wide Field

I rigged up the new ST8i with a 55mm SLR lens and a 2X teleconverter and mounted it atop the LX200 for some wide field imaging. I pointed the telescope at Alnitak and the region of the Horsehead (where I took my first ever image with this camera - see the Nebula gallery) to take the shot at right. I took 20x60 second unguided images and picked out the best one. The field of view of this setup is around 102x154 arcminutes, much too large to pick out the horshead, although the region of this dark nebula can be seen as a faint blob at about the 1 o'clock position relative to Alnitak. Alnitak is the star at bottom center, with a small blooming streak coming out of the bottom. The corners of the image are mostly dark, and spikes can be seen in the stars at the edges. This means field rotation, which means that the polar alignment is off. This is a little surprising because I thought it was good. The weather lately has been alternating between -5 to 5 degrees F at night, and over 40 during the day. I think the heating and cooling has caused my wedge to shift a bit.