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.
The color negative of the full moon looks very similar to the moon during a total lunar eclipse. This exposure (below) was taken with my 10″ f/4.5 Newtonian with a primary mirror figured and coated by Optic Wave Labs (OWL). I did very little in the way of processing the RAW file. I ran the Noise Ninja plugin to cut down on the color noise inherent in DSLRs and to sharpen things up slightly. Then I used Photoshop’s builtin color negative effect to invert everything.