Q lens DOF scale widely inaccurate

[Surfheart]

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I tend to use my M and Fuji bodies with hyperfocal focusing.

On my M lens the infinity mark comes to a hard stop on the index line whereas on the Q the infinity mark keeps going left past the index line by about 2 stops.

The reason I'm just noticing this is because I've only just used my Q for some landscape and used hyperfocal at f8 (placing the infinity mark at f8 on the right side of the index line)

The images came out soft, at first I thought it was an issue with the lens.  

So doing some tests I found to use hyperfocal at f8 I need to place the infinity mark around the f4 mark on the right of the index line.

 

Is this anyone else's experience or is there an issue with my lens?

 

I find this disappointing, one of the attractions of the Q was a proper DOF scale on the lens, on my M lenses, hyperfocal is super accurate.

 

 

[jaapv]

 

 

   Why would you use hyperfocal when you can (auto) focus. It is a technique that one can use when proper focusing is difficult and on vintage simple cameras with flower,stick man,stick family and mountain pictograms. 

 BTW, I would would never call hyperfocal “super accurate” it is controlled misfocus, as DOF depends on subject distance, subject contrast and structure, print size and viewing distance. A scale can be nothing more than a limited approximation. 

However if you are lamenting the lack of a hard infinity stop on the camera I do see your point. 

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[HighlandK]

I agree that hyperfocal focussing involves a guesstimate. On my two Nikon PC-E lenses which are manual focus the infinity mark always stops beyond the symbol. I always understood this was to do with infrared focussing. Cannot speak for Leica M lenses.

[Surfheart]

16 hours ago, jaapv said:

Why would you use hyperfocal when you can (auto) focus. It is a technique that one can use when proper focusing is difficult and on vintage simple cameras with flower,stick man,stick family and mountain pictograms. 

 BTW, I would would never call hyperfocal “super accurate” it is controlled misfocus, as DOF depends on subject distance, subject contrast and structure, print size and viewing distance. A scale can be nothing more than a limited approximation. 

However if you are lamenting the lack of a hard infinity stop on the camera I do see your point. 

I'm terrible at estimating distance and I found that since starting to use Leica cameras with the DOF scale on the lens I really enjoy zone and hyperfocal focusing using the lens scale.

Compared to my M lenses and the only other lens I have a scale on, a Zeiss 80mm Hasselblad lens, the scale on the Q is inaccurate.  My testing has shown that I need to compensate by two stops on the scale to achieve sufficient hyperfocal focus.

Now that I am aware of this I can still use the scale however it's disappointing that the scale is incorrect.

[jaapv]

Errr... You don't have to estimate distance, you paid a lot of money for the M to have a rangefinder, in fact that is the essence of the system, and the Q has both autofocus and focus aids in an excellent EVF.

The DOF scale on any lens, including Leica, is quite inaccurate, as is  dates back to thick-emulsion film and small 6x9 cm prints; on digital sensors and larger prints or screen viewing you need to deduct at least one and for critical work two stops from the actual aperture value.

[Daedalus2000]

16 hours ago, jaapv said:

Errr... You don't have to estimate distance, you paid a lot of money for the M to have a rangefinder, in fact that is the essence of the system, and the Q has both autofocus and focus aids in an excellent EVF.

The DOF scale on any lens, including Leica, is quite inaccurate, as is  dates back to thick-emulsion film and small 6x9 cm prints; on digital sensors and larger prints or screen viewing you need to deduct at least one and for critical work two stops from the actual aperture value.

He did not ask for advise if he should use hyperfocal focusing, that was not his issue. He asked why the markings are two stops off, which is an important issue. He also said that his Leica M lenses are very accurate, so your second point is incorrect..

Instead of discussing the issue he raised you are diverting the discussion on something that he did not ask any advise for.

To the OP thanks for making us aware of it, I will check it with the Q2 when I get a chance to play with it.

Edited March 18, 2019 by Daedalus2000

[jaapv]

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My answer explains exactly why DOF markings  in general are inaccurate. Read it.