Had opportunity a few months ago to get out under a new moon and give my new Sony 20mm f/1.8 prime lens a test and see how it stacked up against the Sigma 20mm f/1.4 which I had been using for quite a while. Both are awesome lenses with the Sigma is also noticeably brighter, however it has its faults. And that is heavy coma up in the corners which unfortunately do not clear up a great deal as you stop down the lens. It is this fault that had me very interested in the Sony 20mm option from the moment it was announced and in this video we take a bit of a look at how they compare. Finishing off the video is a time lapse taken over several hours using these two lenses on my A7S and A7R.