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Hhn J

Hhn J

2-13-24. After passage of a snowstorm I had a few clear hours with turbulent skies. I did a 20 minute test exposure on the horsehead using a Canon 400mm f/2.8 lens stopped down from 135mm to 113mm with an aperture mask. I used it attached to a ZWO ASI533MC Pro camera and just did tracking on my EQ6-R Pro mount. The result was pretty bad. Stars showed some coma and any small telescope would have done a better job. It looks like I'll use this lens in the daytime but not so much for deep sky AP.

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