Archived posting to the Leica Users Group, 2007/01/01[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]
Richard, but if that was happening then photographing the white wall I mentioned would show different exposures for the two lenses, and it doesn't. Remember that the aperture is the ratio between focal length and iris diameter - so the aperture on a 35mm lens @ f1.4 is physically smaller than f1.4 on a 50mm lens. Steve On 1/1/07 11:10, "Richard" <email@example.com> wrote: > Steve, I could be wrong, but think of it this way: the exposure value for > the mid-tone must be the same, but the total number of photons gathered > must be larger for wider angle lens. > > At 03:04 AM 1/1/2007, Steve Unsworth wrote: >> I'm sorry Tina, but I don't get this. Imagine you were photographing a >> white >> wall that filled the viewfinder for both the 35mm and 50mm lenses. The >> exposure for each lens would be identical - i.e. both lenses would have >> the >> same shutter speed / aperture. You can't say that because a lens is wider >> it >> somehow sucks in more light at a given aperture - if that was the case >> hand >> held meters wouldn't work over a range of focal lengths.