Archived posting to the Leica Users Group, 1997/10/01
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Paul Schliesser wrote: > > > I know which way to turn the helical on my SLR to focus closer or farther > away. My point was that you don't always know which way you need to go. > If your subject is slightly out of focus, how do you know if you are > focused too close or too far? If the background or foreground is sharper, > you can tell, but this means you need to study the viewfinder image > first. If you have an isolated subject, I can't see any way that you > would automatically know which way to turn the lens. > > On a rangefinder camera, however, the offset of the rangefinder patch > always tells you if you are too close or too far away. > May be I am missing something, but you can always tell which direction to turn using the semicircle focusing aid of an SLR. Just aim the isolated subject in the two semicircles in the center of the ground glass, the horizontal offset between the top and bottom half of the split image tells you which way to turn the lens, very much like the double image in the rangefinder. I personally almost never use the ground glass for focusing because it's too slow and sometimes too hard. Most manual focus SLRs, including R-series, have the split image focusing screen. It may not work very well when you use a lens with an aperture smaller than f/4 though. - -- - ------------------------------------ G. Huang gang@bell-labs.com - ------------------------------------