JimKasson Posted December 16, 2013 Share #3701 Posted December 16, 2013 Advertisement (gone after registration) Many thanks Jim. My Novoflex NEX/LEM adapter varies in thickness between 9.71 and 9.75 mm. If you have an adapter whose flange thickness varies according to where on the circumference you make the measurement, there are two possibilities, neither of them good. The plane of the back part of the adapter is not parallel to the plane of the front part of the adapter. This means that you have a "tilt" (in view camera terminology) in the adapter. Unless the moons and all the planets align and the tilt occurs in just the right orientation and amount to keep your foreground and background simultaneously sharp, this is A Bad Thing. The surface of either the front side or the back side, or both, does not lie in a plane. This is a recipe for light leaks and mechanical instability. I'm hoping that I'm misinterpreting your comment. Jim Link to post Share on other sites More sharing options...
Advertisement Posted December 16, 2013 Posted December 16, 2013 Hi JimKasson, Take a look here The Sony A7 thread [Merged]. I'm sure you'll find what you were looking for!
JimKasson Posted December 16, 2013 Share #3702 Posted December 16, 2013 So, which Leica M lenses have an FLE? I am aware of the 50 mm and 35 mm ones. How about the 75 APO Summicron? Not having the correct thickness, what are the consequences for FLE lenses? This is above my pay grade, but I'm sure that there are those who can answer your questions. I don't have much inexperience with dealing with floating elements in Leica glass, but I have the sense that they are used to mitigate defects that would otherwise occur as you focus the lens. In the SLR world, leaving zoom lenses aside, floating elements are often used to give long lenses mechanical stability by not making them get longer as you focus. In this case, the focal length of the lens changes as you focus, getting shorter as you focus closer. There are some lenses, particularly macro lenses, that combine the two approaches, both racking the lens out and shortening the focal length as you focus closer. In these lenses, moving the flange distance toward the sensor plane would force the lens to a shorter focal length than it would use with a flange distance further forward. Sorry I can't help more. Jim Link to post Share on other sites More sharing options...
k-hawinkler Posted December 16, 2013 Share #3703 Posted December 16, 2013 If you have an adapter whose flange thickness varies according to where on the circumference you make the measurement, there are two possibilities, neither of them good. The plane of the back part of the adapter is not parallel to the plane of the front part of the adapter. This means that you have a "tilt" (in view camera terminology) in the adapter. Unless the moons and all the planets align and the tilt occurs in just the right orientation and amount to keep your foreground and background simultaneously sharp, this is A Bad Thing. The surface of either the front side or the back side, or both, do not lie in a plane. This is a recipe for light leaks and mechanical instability. I'm hoping that I'm misinterpreting your comment. Jim Thanks again Jim. Understood. That's what I measure and I don't think you are misinterpreting my comment. To me it looks like the side facing the lens isn't perfectly flat. On the positive side the Novoflex adapter seems to be built with shimming in mind on just that non-flat side. Link to post Share on other sites More sharing options...
ModernMan Posted December 16, 2013 Share #3704 Posted December 16, 2013 This is also an issue for those zoom lenses where the parfocality (constant focus while over the zoom range) depends on infinity focus calibration. Link to post Share on other sites More sharing options...
Thomas Chen Posted December 16, 2013 Share #3705 Posted December 16, 2013 Many thanks Jim. So, which Leica M lenses have an FLE? I am aware of the 50 mm and 35 mm ones. How about the 75 APO Summicron? 21 Lux ASPH 24 Lux ASPH 35 Lux ASPH FLE 50 /0.95 Nocti 50 Lux ASPH 50 Cron AA 75 Cron ASPH all with floating element To my knowledge the floating element is mainly to help accurate focusing on M8 and M9 at close distance. Of course with some kinds of better aberration correction. Link to post Share on other sites More sharing options...
k-hawinkler Posted December 16, 2013 Share #3706 Posted December 16, 2013 Many thanks Thomas. I have the 50 Summilux and a 75 Cron ASPH. May be I should get one of my adapters shimmed to avoid the issue? Hmm. Link to post Share on other sites More sharing options...
Jeff S Posted December 16, 2013 Share #3707 Posted December 16, 2013 Advertisement (gone after registration) Here are some preliminary thoughts on the camera from Roger at lensrentals. Jeff Link to post Share on other sites More sharing options...
k-hawinkler Posted December 16, 2013 Share #3708 Posted December 16, 2013 Here are some preliminary thoughts on the camera from Roger at lensrentals. Jeff Thanks Jeff. Very interesting. I wonder how the Otus 55/1.4 would do against the AA 50? One on A7R, the other on well M240! Link to post Share on other sites More sharing options...
viramati Posted December 16, 2013 Share #3709 Posted December 16, 2013 I feel for all you Guys as I bought a seemingly unknown used chinese adaptor for £10 when I got my A7 and it seems to perform faultlessly!!! Link to post Share on other sites More sharing options...
gyoung Posted December 16, 2013 Share #3710 Posted December 16, 2013 That rather shakes my faith in Novaflex, these are not cheap ebay items, for that money they should be RIGHT. Bad enough being too short but not flat is amazing. I would send them back as not fit for purpose, as I did with a fairly cheap m4/3 one once, from a british supplier, they swopped it for one that was exactly right at infinity. Gerry Link to post Share on other sites More sharing options...
k-hawinkler Posted December 16, 2013 Share #3711 Posted December 16, 2013 Hi Gerry, BTW it's Novoflex not Novaflex. A Nova or Supernova are interesting astrophysical phenomena though very different indeed. May I suggest you are overreacting. I measure similar variations in thickness on all of my adapters. Whether that's significant photographically is a different question. As far as I am concerned the Novoflex adapters are extremely well made. That's what I prefer to use with the A7R, especially on a tripod. The Phigment adapter is best on the NEX-7 as it provides missing UI features. I'll leave it at that. Link to post Share on other sites More sharing options...
gyoung Posted December 16, 2013 Share #3712 Posted December 16, 2013 I thought it vwas Novo, but the post I replied too said Nova and I hadn't time to check. With all due respect, an adapter that isn't flat is NOT well made, its so fundamental, and I wouldn't stand for a lens that was mounted so it focussed beyond infinity, so why an adapter, its only a glorified extension tube, and they have been around for a while Gerry Link to post Share on other sites More sharing options...
k-hawinkler Posted December 16, 2013 Share #3713 Posted December 16, 2013 I thought it vwas Novo, but the post I replied too said Nova and I hadn't time to check.With all due respect, an adapter that isn't flat is NOT well made, its so fundamental, and I wouldn't stand for a lens that was mounted so it focussed beyond infinity, so why an adapter, its only a glorified extension tube, and they have been around for a while Gerry Well, you seem to trust my old eyes more than I do. Link to post Share on other sites More sharing options...
gyoung Posted December 16, 2013 Share #3714 Posted December 16, 2013 If you focus a lens by scale, as I often do with very wide angle lenses, you need an accurate scale and a correct, hard infinity stop. These are some of the best points of Leica lenses versus any others I can think of, focus scales have become so compressed as to be virtually useless. Indeed with the 15 Heliar and the 25mm Skopar it is the only way on a film M camera. When I tried them on a Panasonic G1 EVIL camera it was very frustrating to focus on Live View with such short focal lengths, with my old eyes So the scale was still important. To lose that capability because they won't trouble to make the adapter to give correct registration would be most disappointing. And not to have the lens and camera mounts parrallel (within fine tolerances) is pretty pathetic, IMHO. I don't expect my cameras to have swing on the mount unless I put it there! Gerry Link to post Share on other sites More sharing options...
k-hawinkler Posted December 16, 2013 Share #3715 Posted December 16, 2013 If you focus a lens by scale, as I often do with very wide angle lenses, you need an accurate scale and a correct, hard infinity stop. These are some of the best points of Leica lenses versus any others I can think of, focus scales have become so compressed as to be virtually useless. Indeed with the 15 Heliar and the 25mm Skopar it is the only way on a film M camera. When I tried them on a Panasonic G1 EVIL camera it was very frustrating to focus on Live View with such short focal lengths, with my old eyes So the scale was still important.To lose that capability because they won't trouble to make the adapter to give correct registration would be most disappointing. And not to have the lens and camera mounts parrallel (within fine tolerances) is pretty pathetic, IMHO. I don't expect my cameras to have swing on the mount unless I put it there! Gerry Thanks. For your needs you probably want a correctly shimmed adapter. Link to post Share on other sites More sharing options...
tgm Posted December 16, 2013 Share #3716 Posted December 16, 2013 Have you seen this? LensRentals.com - Sony A7R: A Rising Tide Lifts All the Boats? I think it is interesting for all the folks who believe that the A7R will give superior image quality with Leica M lenses. Actually, it seems in the center yes, but in the corners no. Thomas Link to post Share on other sites More sharing options...
Mr_Jones Posted December 16, 2013 Share #3717 Posted December 16, 2013 It's very easy to see when you compare everyday shots from the two cameras. I guess empirical testing is reassuring. Link to post Share on other sites More sharing options...
Nick De Marco Posted December 17, 2013 Share #3718 Posted December 17, 2013 I just got the A7R this weekend My blog discusses my first impressions, with photos, of this lovely little camera... Rangefinder Chronicles: Sony A7R at the weekend One of my quirky favourites (that works), 35mm Summicron v1 with goggles on the A7R Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/214267-the-sony-a7-thread-merged/?do=findComment&comment=2488786'>More sharing options...
Jeff S Posted December 17, 2013 Share #3719 Posted December 17, 2013 Have you seen this? Yes, and posted here yesterday on the related thread. Jeff Link to post Share on other sites More sharing options...
Bill W Posted December 17, 2013 Share #3720 Posted December 17, 2013 Good to know, I was going to just stick with my crummy old M. Link to post Share on other sites More sharing options...
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