My wides at F2

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Fraser

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Just did a quick sharpness test on my M9 with my wides,
28mm summicron
35mm summilux pre asph (at F2)
35mm Canon F2 Ltm

And the sharpest yes you guessed it the Canon:rolleyes:
 
did you focus bracket?

I would be surprised if the Canon was sharper than the 28 summicron. Can't speak to the pre-asph 35 lux, but the 28 cron has measurements that were simply impossible to achieve in the days when the Canon was designed and everything I've seen sample wise has confirmed that.
 
redisburning said:
did you focus bracket?

I would be surprised if the Canon was sharper than the 28 summicron. Can't speak to the pre-asph 35 lux, but the 28 cron has measurements that were simply impossible to achieve in the days when the Canon was designed and everything I've seen sample wise has confirmed that.
Click to expand...

Its a bit unfair for the 28 as it more of a crop and maybe not much in it between the cron and the Canon. I think probably the 28 is just a bit less contrasty and is smoother between tones (if you know what I mean). But what surprised me more was how good the canon was next to the summilux.
The only reason I bought the Canon was because it a good deal.
I maybe should bracket my focus maybe I was just luckier with the canon.
 
I sometimes compare lenses, and I always use a heavy tripod with a cable release, and I use a magnifying glass/loupe to assist with focusing. It is important to hold extraneous sources of variability to a minimum.
 
Fraser said:
Moral of the story don't start testing lenses. Focus of my 28mm is out by about 5cm at .8m.
Click to expand...

Yes, precision focusing in the range near minimum focus distance with a rangefinder camera is always suspect.

When I check lenses' resolving power (rare!), I photograph brick walls or newsprint at 5 to 10 foot distances, particularly for RF cameras. I only test lenses at sub-meter distances if it's a macro lens and an SLR or TTL electronic view camera.

More variability in apparent sharpness or acutance comes from hand-holding the camera than anything else, so I wouldn't bother testing without a sturdy tripod either.

G
 
Live view is your friend when you want to check the glass without the RF interfering.
Of course, a simple ruler test will give you an answer on whether your lens is calibrated or not.
 
Godfrey said:
Yes, precision focusing in the range near minimum focus distance with a rangefinder camera is always suspect.

When I check lenses' resolving power (rare!), I photograph brick walls or newsprint at 5 to 10 foot distances, particularly for RF cameras. I only test lenses at sub-meter distances if it's a macro lens and an SLR or TTL electronic view camera.

More variability in apparent sharpness or acutance comes from hand-holding the camera than anything else, so I wouldn't bother testing without a sturdy tripod either.

G
Click to expand...

I tried it again and seems the focus is ok once you get over 1m I dont think my eyes can focus anymore accurately, but seems the Canon is pretty good and for some reason I seem to have less trouble focusing it.
 
Fraser said:
I tried it again and seems the focus is ok once you get over 1m I dont think my eyes can focus anymore accurately, but seems the Canon is pretty good and for some reason I seem to have less trouble focusing it.
Click to expand...

Likely a quirk of the lens-rf cam interaction, but eh? Life's too short.

The Canon 35mm sounds like a very nice lens for not a lot of money. Always value in that ... :)

I tend to use RF cameras with an assumption of their constraints on focus accuracy in mind. TTL electronic and SLR cameras, where you can see the image formed by the lens, are what I use for critical focusing. The new M, with TTL electronic viewing (aka Live View), expands the Leica M's versatility in this regard.

Godfrey
 
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