9 April 2020

Week 3 of the Cov-19 lock down. Luckily it has coincided with a period of clear albeit, somewhat hazy, skies.  With no need to commute, I can now stay up a bit later and still be at work on time.

Having spent several days on the moon last week it was a pleasant change to visit Venus in the evening sky. Although called the evening star, Venus is still visible well after 2300L so is now really the night time star.

I have to be careful with my Venus observations. From my observatory, it is only visible for about 20 minutes when it passes between 2 trees. I need to have the telescope ready with Venus centred and focused as best I can on the laptop screen so that I can capture frames as soon as there are no obstructions.

I spent the afternoon upgrading my elderly version of firecapture to the latest v2.6.08 and, after a hasty reinstall when it didn’t work, used the tool to effectively set up my ZWO Atmospheric Dispersion Corrector (ADC). This provides a much cleaner image by eliminating the red and blue fringing caused as the light refracts through the atmosphere.

It required careful judgement as the image danced all over the screen with poor seeing and changes in focus. Having then sharpened the best 500 of 10,000 stack in Registax, it only needed a nudge of 1 pixel to be completely aligned – an imperceptible amount.

Good practice for the Mars opposition later this year, hurrah!