Just purchased a Leica 90mm APO-summicron-M lens

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driggett

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First off I have to say I love this lens for it's compactness, it's absolute vivid color rendition. But I think I have a focusing problem. I shoot tball games last Sat. and everything was out of focus when I shot at f/2. I was being the 1st base coach when shooting the players as they batted. Wonderful expressions, timing and color but all out of focus! I then did a test and I have noticed that the rf is focusing on the subject but the lens is set a little in front. For instance the picture below. I focused on the snapple label but the natural word on the Styrofoam cup is in focus. I checked in the rangefinder and the natural was not in focus but the right hand circle of the snapple label was. I have done several tests shots like theses this morning and they all came out the same. The other lenses 50, 35,28,21,15 seem not to have this problem. Is it only this lens with this camera?

Also why when I use Epson's camera raw I have to apply about 1 stop of more exposure when I convert photos but I do not have to do this when use RawDevewloper or Adobe Raw. Has anybody seen this also?

Thanks,
Chris
 
Focussing accurately at f/2 with a 90mm lens is not possible on the R-D1 otherwise than by chance... or genius i'm afraid.
You'd need something like a 60mm RF effective baselength for this purpose when the R-D1's is only 38.2mm.
Best,
LCT
 
Thanks LCT.
So based on the rangefinder lengths or baselines what apertature should I be shooting at? also would a magnafier help or is it just not happening because of the base lenght?
Thanks,
Chris
 
According to the usual formula, f/ 3.5 should do it normally.
The widest aperture of 90mm lenses for Leica CL or Minolta CLE was f/4 due to the short baselength of their RFs as well.
Best,
LCT
 
Roughly, the widest apertures we can use accurately on the R-D1 are:

28mm: wider than f/ 1.0
35mm: wider than f/ 1.0
40mm: wider than f/ 1.0
50mm: f/ 1.0
75mm: f/ 2.4
80mm: f/ 2.8
90mm: f/ 3.5

Best,
LCT
 
Strange, Going by the tables on that page I shouldn't be able to use
my 135mm Elmar, but I can.....I admit I did get quite a few OOF
but percentage wise perhaps 15-20%...
Mike
 
Of course you'll get good results at the infinite at any aperture with your 135mm lens.
Otherwise, it will be difficult at wider apertures than f/8...
Which does not mean that it is impossible of course.
That pic has been shot at f/ 5.6 with an Elmar 135/4.0 for example.
Best,
LCT
 
BTW Cosina Voigtlander 75mm and 90mm lenses are opened at f/ 2.5 and 3.5 due to the short baselength of the Bessa's RF i guess.
Best,
LCT
 
See hear is a question. How does the Cosina Voightlander 90mm lens compare to the Leica 90mm f/2 shot at f/4? Is the quality of the color and sharpness the same. One thing I have noticed is that my Leica lenses blow the pants off of the CV lenses in terms of color and sharpness.
Thanks,
Chris
 
I was going to disagree with the postings here, because despite the physics involved, there is something about the R-D1's rangefinder (I have mentioned this before) that makes focusing more accurate, as images seem to pop into clarity rather than focus. Others have noted this too.

So I went of with my 90AA to prove my point. I took shots wide open at 1 meter, 2 meters, and 3 meters, focussed on the cookie box. The first 2 shots were pretty much right on, but the one at 3 meters was hard to get accurate focus the first time. Overall, there was more of a problem with camera shake than focus, though, at the closer range. I think that if the focus target had been larger, though, my 3 meter shot would have been easier.

If a 90AA does not focus right, it is likely to be RF adjustment rather than poor focusing, IMO. The R-D1's RF is a champ for focus, despite its short base, if all is set up right.

Ed
 
I haven't got focusing problems with most of my M lenses so far but the R-D1 is much less accurate than any of my 0.72x, 0.85x or 0.91x M bodies to be honest...
Best,
LCT
 
I have no trouble accurately focusing my LTM 85mm Sonnar at f/2 on the R-D1. The Sonnar goes down to 85cm, and I can nail the focus at this distance consistently. This seems to defy the laws of optics--short RF baselength, long-ish focal length--but it works fine nonetheless. :cool:

-Dave-
 
It's an awesome lens- I really like mine, and I like the "nearly macro" feature of close focusing it- I get much more on film close than with the 35mm.
 
Chris,
I suggest you check out if the front focus problem is not caused by a Cam compatibility problem. I can focus my Tele-Elmarit f/2.8 consistantly at full aperture (as long as I do it carefully), but my 35mm f/2 Cron front focuses as noted before.

Try the usual angled shots against a ruler or across a newspaper at full aperture preferably on a tripod. Repeat a few times (defocus and refocus each time) and if the front focus amount is consistant its probably the cam. If the sharpest point is more radom in each photo its down to the inability of the rangefinder base to achieve focus.
 
Jim,
I have tried those tests and the focus point is in front of the point I focused at consistently at about the same spot. I have no problems in focusing my other lenses. Is there a special adjustment for this lens to be made to the camera or lens itself?
Thanks,
Chris
 
Chris,
If its consistantly front focusing by the same amount then its almost certainly the compatibility between the Cam & the R-D1's Cam follower and it is a bit of a problem with no easy solution.

First I would try to check the lens on a Leica M body to see if the front focus problem occurs here as well. Should it be out by a similar amount a good repairer should be able to adjust the cam to work with both cameras, but it will probably be O.K., my 35mm Cron is fine on my M4.

If you only intend to use this lens on the R-D1 you could still have the lens cam shimed or reground to match the R-D1 BUT it then would probably not be accurate on other cameras and it would be unethical if you sold it on in future in this state. It might also be fairly expensive.

You could adjust the R-D1 rangefinder to give better focus with this lens but then the cameras rangefinder would not be accurate with your other lenses so this dosn't seem a good idea. One member here had already adjusted his R-D1 to match a front focus 35mm Cron like this before he realised the implications. So its a very limited solution.

If its not out by much and in most cases is covered by DOF you could live with it. This is what I do with my Cron remembering to back focus a little when in close at wide apertures. This of courses is easier with a 35mm lens than a 90mm so is probably not acceptable in your case.

Lastly and possibly the best solution if you purchased from a dealer is to try and exchange it for another example of the same lens with a different vintage (fairly big difference in serial numbers). The 35mm Crons are a bit problematic in this respect with all type 3 & 4 from Canada between 1975 & 1985 (and probably wider) I have seen having the problem. Later 35mm asph's seem O.K. but I can't afford the upgrade. Yours is the first focus problem I have heard of with the 90mm f/2 so you might be luckier.

Is your example Canadian (Midland, Ontario)? If so see if you can try a Wetzlar example.
 
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