Timmyjoe Posted January 24, 2014 Share #1  Posted January 24, 2014 Advertisement (gone after registration) I just picked up a 90mm Elmarit-M and noticed something I had not seen before with the aperture blades.  When set at f2.8 (wide open) they are pretty much out of the way when you look through the lens.  When you stop the lens down half a stop, f2.8 and a half, the aperture looks like this:  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!  Very jagged.  When you stop the lens down a full stop, f4.0, the aperture smooths out somewhat like this:   And it's not until you stop the lens down another half stop, f4.0 and a half, that the aperture smooths completely out like I am used to seeing aperture blades.  For anyone who has this lens, is this normal for the lens, or does this one need to be serviced?  Thanks for any and all info on this. Link to post Share on other sites Simply register for free here – We are always happy to welcome new members!  Very jagged.  When you stop the lens down a full stop, f4.0, the aperture smooths out somewhat like this:   And it's not until you stop the lens down another half stop, f4.0 and a half, that the aperture smooths completely out like I am used to seeing aperture blades.  For anyone who has this lens, is this normal for the lens, or does this one need to be serviced?  Thanks for any and all info on this. ' data-webShareUrl='https://www.l-camera-forum.com/topic/220799-is-this-normal-for-90-elmarit-m/?do=findComment&comment=2517305'>More sharing options...
Advertisement Posted January 24, 2014 Posted January 24, 2014 Hi Timmyjoe, Take a look here Is this normal for 90 Elmarit-M. I'm sure you'll find what you were looking for!
CheshireCat Posted January 24, 2014 Share #2 Â Posted January 24, 2014 My Elmarit-M (11807) does exactly the same. Link to post Share on other sites More sharing options...
pop Posted January 24, 2014 Share #3 Â Posted January 24, 2014 So does mine. Link to post Share on other sites More sharing options...
Peter H Posted February 3, 2014 Share #4 Â Posted February 3, 2014 Mine too. Link to post Share on other sites More sharing options...
mikebidwell Posted February 3, 2014 Share #5  Posted February 3, 2014 I get a similar effect with my Leitz Tele-Elmarit M f:2.8/90mm  :D Best wishes  Mike Link to post Share on other sites More sharing options...
adan Posted February 3, 2014 Share #6  Posted February 3, 2014 It is fairly common across a wide range of Leica M lenses, especially pre-1990 lenses. Mostly due to the size constraints of fitting blades into a small lens (and also keeping the aperture action linear, so that the stops marked on the ring are spaced equally.)  90 Tele-Elmarit: http://kenrockwell.com/leica/images/90mm-f28-tele/D3S_5203-1200.jpg  90 Summicron from the 60s-70s: http://www.kenrockwell.com/leica/images/90mm-f2/silber/D3S_9780-1200.jpg  Some of the Schneider/Leica Super-Angulon 21mm lenses could only fit 4 blades, so the aperture was always a square. Link to post Share on other sites More sharing options...
2wk Posted February 3, 2014 Share #7 Â Posted February 3, 2014 Advertisement (gone after registration) Even the 50 Summilux APSH does this. The first time I saw it I thought my lens was a dud as well. Link to post Share on other sites More sharing options...
mmradman Posted February 3, 2014 Share #8  Posted February 3, 2014 Exactly my experience with my first Leica lens, after some initial anguish & head scratching I learned  Recently I revisited some old Pentax SMC-M lenses collecting dust and re-discovered same serrated star pattern. Link to post Share on other sites More sharing options...
UliWer Posted February 3, 2014 Share #9 Â Posted February 3, 2014 It is fairly common across a wide range of Leica M lenses, especially pre-1990 lenses. Mostly due to the size constraints of fitting blades into a small lens (and also keeping the aperture action linear, so that the stops marked on the ring are spaced equally.)Â .... Â Well, you might call your explanation an euphemism for limiting production costs. Did you ever look at the blades of an old f4/90mm Elmar? The most constraint 90mm lens as far as fitting blades into it, but - very round even between f-stops. With the first Elmarit they started to reduce the number of the blades, which resulted in odd shapes especially between f-stops. The late 3-lens version of the 90mm-Elmar -excellent as it is- also shows these odd shapes. Â Most famous example is the 50mm Summitar: the wartime and first post-war versions had round shape of blades, the later version had a hexagonal shape - same lens, same size of the housing, just cost-reduction. With the more expensive collapsible Summicron they came back to the round shape. Link to post Share on other sites More sharing options...
rramesh Posted February 4, 2014 Share #10 Â Posted February 4, 2014 And how it would it impact pictures? as I don't see anything wrong. Link to post Share on other sites More sharing options...
UliWer Posted February 4, 2014 Share #11 Â Posted February 4, 2014 Usually the shape of blades does not matter - though if you look at bright spots in the bokeh you might percieve a difference between a round shape of the lenses opening and other shapes with angled edges. Link to post Share on other sites More sharing options...
Paul J Posted February 4, 2014 Share #12  Posted February 4, 2014 It does impact the pictures.  I have the same thing on my Summilux 75 at mid apertures and it chops up the bokeh on certain things like trees. Personally I find it distracting in some cases, and it's something I always aware of with some busy OOF areas at these apertures.  It just depends on the what the subject is, but busy detailed bokeh, like trees, looses it's smoothness and become choppy when you get a star shaped aperture.  Sometimes it works because it looks painterly, it just depends on what you are shooting and if it suits the image. But it pays to take note of what apertures, give what shapes, so you can be aware of it when shooting.  I suspect the diminutive size of an M lens makes a round aperture harder to achieve, from an engineering perspective. This is one of the main reasons a lenses character will change through out an aperture range. It's actually one of the first things I look at when I get a new lens so I know what to expect.  f4 and 1.4 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/220799-is-this-normal-for-90-elmarit-m/?do=findComment&comment=2525370'>More sharing options...
CheshireCat Posted February 4, 2014 Share #13 Â Posted February 4, 2014 Curiously, my SEM 21 wide open does not retract all blades and the "mysterious" shape is visible. Link to post Share on other sites More sharing options...
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