Lenses with wide maximum apertures are extremely popular both for working in conditions with low light and for creating images with very narrow depth of field. In recent years, we have seen an explosion of lenses that push well past traditional thresholds like f/1.4 and into extreme apertures like f/1.0 or even f/0.95 and f/0.85. Are these insanely wide lenses worth it? This insightful video discusses the issue.