Originally Posted by
reddesert
Something is wrong with this (simulated 35mm overlaid on 4x5) image. The image of the sun is improperly scaled for focal length. You can tell because the image of the sun should be 10x linearly smaller in the "200mm" image than in the "2000mm" image, but it looks only about 3x smaller.
The sun's disk is about half a degree diameter or 1/110 radian. That means the diameter on film will be about 1/110 of the focal length. So for a 2000mm lens, you get about an 18mm diameter disk on film. The simulated 2000mm image shows the sun nearly filling the 24mm dimension - about 21mm image diameter. So that is maybe 10% exaggerated. For the 200mm image, the sun will be only about 1.8mm diameter on film, but the image shown is about 8-9mm diameter, so simulated 4 - 5 times too large.
As people say, perspective is a property of your viewpoint - "telephoto compression" comes from standing far away and excluding a lot of the foreground/sideground. For which you need to either use a long focal length lens, or crop a lot.
Bookmarks