We had a fantastic time at Stellafane 2016. My first telescope mirror took second place in the small Newtonian optical competition!
Last night the full moon dominated the sky from dusk until dawn. The temperature dropped below freezing and the grass and leaves were covered in frost. I used the night to fine tune the alignment of my optics. I’m not entirely convinced the secondary mirror is at the ideal/correct placement and orientation. The laser collimator was used to ensure the secondary is in correct relation to the primary, which I center-spotted.
For the previous many nights, I had noticed that stars on the left side of the camera frame had more coma or perhaps astigmatism (elongation). I rotated the secondary mirror ever so slightly, readjusted the collimation of everything using the laser and stars, and now I perceive that the stars stretch towards the edges of the frame evenly on both sides now. I’m still very new to all of this and so lots of experimentation is required.
After allowing the primary mirror to cool to equilibrium, which seemed to take a long time, I decided to snap a few shots of the moon. Lunar astrophotography (can we call it that?) has the opposite challenge of deep space astrophotography. The moon is incredibly bright and instead of long exposures, tracking the object as accurately as possible, I reverted to the shortest exposure my camera would allow without any tracking. Any other targets were a loss with all of the light from the moon and the poor atmospheric conditions. I found an interesting article this morning which describes last night’s moon as the last supermoon of the year and also a bit of history around this full moon’s moniker, The Hunter’s Moon. You learn something new every day! ;-)
I sharpened this image every so slightly. It’s possible to sharpen it up and increase the contrast so that all of the subtle craters pop out and yet I felt that the moon looked rather artificial when enhanced to that degree.
When the moon is full, astrophotographers often have less than an enthusiastic response. It tends to dominate the sky and wash out any hope of observing deep sky objects. I used the beginnings of tonight to try out my new folding table–a big step up from setting things on a Rubbermaid tub. I figured another good use for the bright full moon was to illuminate myself and telescope for a selfie. I tried to hold pretty still for 3 minutes while the exposure unfolded. The hope was to catch the star trails as they seem to revolve around Polaris (made more obvious with software enhanced diffraction spikes).