17 Jun The Flirty Thirty: the Sigma 30 mm f:1.4 DC Art lens
Well what the heck. We have talked about 50mm focal length lenses as "The Nifty Fifty" for years. Why not push the linguistic boat out, eh?Why not indeed. And there are good mathematical reasons why you should consider this focal length. As mathematics are the food of the photographer let us begin the feast.The standard focal length of a lens for a 35mm camera used to be stated as 50mm. It also used to be stated that the standard focal length was the diagonal length of the gate in the film plane. Here's where the two statements differed: the diagonal of the 35mm frame is about 43.4 mm. Thus if you were shooting with a 50 mm, 52 mm, or 55 mm said to be standard you were really shooting with a very mild telephoto...