I was just playing around with a Minolta MD to Sony AF adapter with no glass optics. We all have heard that Minolta MD's and Canon FDs will be macro lenses on a Canon 5D/7D/EOS but I've always wondered just how macro is macro??
The Flange to focal distance length for my Sony A900/AXXX is 44.5mm which is just .5mm greater than the Canon EF (EOS) mount.
I found it interesting that the longer lenses 135mm and beyond actually have a very usable focus distance range, to about 12/13 feet and can be used for a lot of indoor photography. They still don't hit infinity, but they are certainly not just "macro" lenses.
I'm not sure what optical physics are involved, but the shorter the focal length, the more macro the lens becomes. At 50mm, you can't focus beyond a few feet, with a 28mm, even shorter.
I'm delighted that I can use my super nice Minolta 135mm F2.8 PF on a Sony and in the future a Canon 7D, maybe not for videography, but it can still serve as a nice portrait lens.
The same optical rules must apply for Canon FD lenses, the only caveat being that the FD mount flange distance is even shorter than the Minolta MD one, at 42mm so even a 135mm FD may be more macro than I am reporting here and so may not have as useful a range.
I don't own any FD lenses so I can't test it out.
One other optical rule - and this one I was well aware of - comes from my experience with using bellows on my Mamiya RB67 which basically draws the focal distance out further from the flange plane - and it is that your image gets darker the further it is away from its intended plane. On film this would have to enter into your calculations but with digital you can just see the results and adjust your lighting/exposure for it.
The Flange to focal distance length for my Sony A900/AXXX is 44.5mm which is just .5mm greater than the Canon EF (EOS) mount.
I found it interesting that the longer lenses 135mm and beyond actually have a very usable focus distance range, to about 12/13 feet and can be used for a lot of indoor photography. They still don't hit infinity, but they are certainly not just "macro" lenses.
I'm not sure what optical physics are involved, but the shorter the focal length, the more macro the lens becomes. At 50mm, you can't focus beyond a few feet, with a 28mm, even shorter.
I'm delighted that I can use my super nice Minolta 135mm F2.8 PF on a Sony and in the future a Canon 7D, maybe not for videography, but it can still serve as a nice portrait lens.
The same optical rules must apply for Canon FD lenses, the only caveat being that the FD mount flange distance is even shorter than the Minolta MD one, at 42mm so even a 135mm FD may be more macro than I am reporting here and so may not have as useful a range.
I don't own any FD lenses so I can't test it out.One other optical rule - and this one I was well aware of - comes from my experience with using bellows on my Mamiya RB67 which basically draws the focal distance out further from the flange plane - and it is that your image gets darker the further it is away from its intended plane. On film this would have to enter into your calculations but with digital you can just see the results and adjust your lighting/exposure for it.
