Focusing Metaphysics

[archi4]

Advertisement (gone after registration)

Lars

My Summilux 50mm ASPH had back focus on my M9.

All my other lenses, including my older tele elmarit 90, focussed perfectly at all distances so I contacted Solms and although they wanted my M9 I said I would send the lens alone at my risk.

Yesterday the lens came back adjusted to "Leica standard" and it is really perfect at all distances. Believe me, I am extremely critical!

If it back focuses at all distances, it may only need shims. Was it coded and maybe the bayonet remounted incorrectly shimmed.

maurice

[jaapv]

Lars:

 

 

index.html

[pop]

Lars - you might find this focus test chart useful: Home.

 

Contrary to what the instructions say, I'd suggest

- to shoot the chart such that the chart's orientation matches the pictures orientation. This also gives a nice vertical to focus on

- and to mount the chart on a vertical surface and shoot from a sideways angle of 45°.

[tobey bilek]

All this is discouraging me from buying a digital M9.

[jaapv]

Because a lens misfocusses and CS is playing silly buggers? I don't see the connection to digital -unless you object to the fact that a sensor is more precise and shows up such failings more easily.

[christer]

If you are serious about checking focusing accuracy it is not sufficient to photograph a yard stick placed on a table as shown in a previous post. You need to use a device like the one pictured below.

 

The distance between the lines with the numbers on the device should be approx 1.4 times what you measure, cm or inches. You can then read off the misfocus directly in cm or inches.

 

The plane photographed should be at a 45° angle to an imaginary line between the lens and the focusing point (the "zero" line).

 

Put the camera on a tripod. You can sit or stand, but the viewfinder should be at eye level and at the same height as the test device. This facilitates accurate focusing.

 

Use a viewfinder magnifier if you have one. Avoid progressive eye glasses if you can. I have found the nail shown on the photo to be very helpful for focusing.

 

The sides of the device shown is approx 30x30x40cm. It can be used for distance up to 2 meters. (I wonder how people determine infinity out of focus. ;-)

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!

[jaapv]

Advertisement (gone after registration)

Very nice - but I think measuring is just trying to confirm. A lens, imo, should be sent in for calibration as soon as the photographer thinks it is misfocussing in normal, daily use. Measuring by whatever method will not take away that feeling.

[lars_bergquist]

Because a lens misfocusses and CS is playing silly buggers? I don't see the connection to digital -unless you object to the fact that a sensor is more precise and shows up such failings more easily.

I agree. That lens would have misfocused on a film M too, though the test image would have been a bit fuzzier.

 

To repeat, my M9 focuses damn well anything perfectly. It's just this single lens that misbehaves. And the correction is not terribly difficult either. it's just that Leica Customer Service has taken its inspiration from the Ministry of Silly Walks.

 

And thanks Jaap, I has just emailed Mr. van Manen.

 

The slightly fuzzy old man

[aesop]

...Lars, I salute your infinite patience. Will test my lenses this weekend - hopefully they will all be within tolerance.

[lars_bergquist]

...Lars, I salute your infinite patience. Will test my lenses this weekend - hopefully they will all be within tolerance.

 

Salute my infinite bloodymindedness instead.

 

BTW my email was answered at once, and Mr van Manen will have my custom.

 

The old man, focused but unbent

[lars_bergquist]

This may be the place to reiterate a very different misfocusing story:

 

When I got my M8 I sorely wanted a real wide angle lens for it. The WATE was not my cup of tea, the Super-Elmar did not exist, so I got myself a Carl Zeiss 18mm Distagon from Leicashop in Vienna. Focusing proved to be miles off. I returned the lens and the people in Vienna mailed me back and told me that they had tested the other Distagon they had, and that too was miles off! So they sent the lens (or probably the lenses) to Zeiss in Oberndorf, who adjusted the thing and sent it back to Leicashop, who returned it to me. The focus of this now well-travelled lens (Japan--Vienna--Stockholm--Vienna--Oberndorf--Vienna--Stockholm) was perfect. So I pulled the bayonet and had John Milich in Brooklyn mill it for coding. Carl Zeiss took full responsibility for their product, and their legendary name, even though Cosina made it! Wonderful lens. I would still prefer it to the Super-Elmar.

 

The old man from the Age of Service

[menos I M6]

I never came to that idea Lars - lifting the lens mount and have it posted to John Milich for coding ;-)

 

Is this the business of John Milich?

About the people at Product and Design metalwork company

 

How much does he charge these days for coding?

 

I am reluctant, sending lenses around the world, to have work done on them.

Does anybody know of a good Leica lens expert in China - Beijing, Shanghai, Hangzhou, Suzhou, Guangzhou?

 

I would love, to have my 90 Elmarit-M's aperture ring adjusted and maybe even the misfocussing 50 Lux ASPH dealt with in a timely fashion.

[lars_bergquist]

I never came to that idea Lars - lifting the lens mount and have it posted to John Milich for coding ;-)

 

Is this the business of John Milich?

That is one of the businesses of John Milich. But John does not code the bayonet, he just precision mills the recesses in the right places, so you can code it with black and white paint. John does also manufacture entire bayonets. I have not been in contact with him lately, but when we did business, his work was good and his service prompt and at a good price. A honest and competent worker.

 

There are not a lot of internal linkages and thingums in Leica M lenses, so removing the bayonet ring is not too difficult (though doing it voids the guaranty, of course). You need a precision-ground, fitting screwdriver and some acetone. Put a drop of acetone on each screw ten seconds before removing it, so that the goo that secures it is softened. Keep a small container ready to keep the infernal little screws in. NOTE: I am not responsible for what happens when you sneeze during the operation and run the screwdriver through the rear element

 

The old man from the Mechanical Age

[jaapv]

I never came to that idea Lars - lifting the lens mount and have it posted to John Milich for coding ;-)

 

Is this the business of John Milich?

About the people at Product and Design metalwork company

 

How much does he charge these days for coding?

 

I am reluctant, sending lenses around the world, to have work done on them.

Does anybody know of a good Leica lens expert in China - Beijing, Shanghai, Hangzhou, Suzhou, Guangzhou?

 

I would love, to have my 90 Elmarit-M's aperture ring adjusted and maybe even the misfocussing 50 Lux ASPH dealt with in a timely fashion.

 

It may well be that a Summilux 50 asph can only be serviced by Leica themselves. The floating element mechanism complicates matters and is made to extremely narrow tolerances.

[gyoung]

I find this all amazing, after all leica cracked lens registration 70 or more years ago with the 'standardised' mount, now we are expecred to pay all that money for cameras and lenses and they have to go back to the factory to be matched???? Maybe the absence of a 0 on the lens mount is significant again !

I sometimes wonder if the modern leica deserves our loyalty.

[jaapv]

Old lenses are made for film - film is imprecise compared to sensors. Old lenses have to be brought into the tolerances that are valid now - the old tolerances are too wide.

[scsambrook]

Old lenses are made for film - film is imprecise compared to sensors. Old lenses have to be brought into the tolerances that are valid now - the old tolerances are too wide.

 

But many of the problems mentioned in this forum are found in recently manufactured lenses whose tolerances ought to be valid for the digital sensor . . .

[jaapv]

You'll find the problems with new lenses are relatively few. Having said that I had to send in a new Summilux 50 asph two years ago...

[elgenper]

Old lenses are made for film - film is imprecise compared to sensors. Old lenses have to be brought into the tolerances that are valid now - the old tolerances are too wide.

 

While this is certainly true as a general principle, there are just too many indications that all is not well in this area. As I said, none of my three old, battered ´60es lenses have any focus problems at all on the M9. The only one that was off was a brand new, coded one, directly out of the box.

 

My recent Leica experience reminds me of when I had cars from the VAG group (Volkswagen, Audi): long delivery times, frequent manufacturing errors, long waiting for service, and a general attitude that one should be grateful to be allowed to buy such great cars...

 

Now, I drive Toyota. Delivered within a week, 10 years without any repairs.

 

If only Leica glass weren´t so d-mn GOOD.....

[Advertisement]

Hallo,

Look here: Interesting Leica gear

[wizard]

Now, I drive Toyota. Delivered within a week, 10 years without any repairs.

 

Oh, sure. Just curious, how many Toyota cars had to be recalled within the last year worldwide? If I remember correctly, that number was approaching or even exceeding 5 million. And now it is Lexus, too.

 

Andy