Watch the video: What is focal length? Take two 50mm lenses: an f/1.8 and an f/1.2. Even though they both have the same 50mm focal length, they're not the same physical length – and neither of them is ...
A new Zeiss Otus ML series lens has been announced, with the Otus ML 35mm f/1.4 lens. Designed to be a well-rounded prime ...
On the first night out with my brand-new Celestron NexStar 8SE back in July 2015, I knew little about the relative sizes of astronomical objects. I was bowled over by my first view of Saturn — an ...