Zone focusing

[benedict297]

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Hi, done a few readings on the web about focus zoning, but still don't quite get it.. I understand that if I select a certain aperture, based on the meter reading, anything within a certain meter will be in range. But where do I need to set focus ring? In order to just shoot anything within a certain range without having to re-focus?

 

Thanks

[gjames9142]

It becomes apparent if you look at the engraving on the focus ring. f11 at ten feet will get you by on a wide angle. Useful for quick-reflex street photography. But any Leica can be quickly focused if you practice a bit.

[LucisPictor]

Depending on aperture and focal length (in practical terms) an area in front of and behind the focus plane is "sharp enough" to be considered "sharp".

 

You can use the engravings on the lens barrel to see that:

 

Example: 50mm lens, f/8

 

The engravings show something like this:

 

..oo...15.....5.....3....2.....1.6

|...|...|...|...|...|...|...|...|

..8...4..|..4...8.....16.....22

 

In this case everyrthing between 5m distance and infinity will be acceptably sharp.

[Paul J]

I always add a stop with zone focusing though. If the scale reads f5.6 then I will select f8 as I find "acceptable" not so acceptable at times.

[Jeff S]

More in this article.

 

If you have an M8, then read the section on DOF markings on the M8 in this LuLa article.

 

But understand that focus is optimized at one place; the rest is 'acceptably sharp,' and that depends on various factors, especially in the eyes of the beholder.

 

Jeff

[Orient XI]

Remember that, except at distances <2.5m, there is more depth behind the point of focus than in front of it. A rough rule is to focus about two-thirds of the distance into the zone of focus.

[LucisPictor]

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I always add a stop with zone focusing though. If the scale reads f5.6 then I will select f8 as I find "acceptable" not so acceptable at times.

 

That is especially true when shooting digitally.

[algrove]

OP-Are you OK with these replies to your initial question?

[jaapv]

But - the operating words are "acceptably sharp" This varies with the type of subject (lots of detail or bold shapes), the contrast of the subject (a misty scene needs less sharpness than a sunny subject) and personal level of acceptance - but most importantly enlargement. A 6x4 print can look tack sharp from foreground to horizon, when you blow it up to 60x40 the plane of focus will be blindingly obvious.

For general photography it is safe to assume that the only sharp plane in the image will be the one you focussed on. Zone focus can be useful in hectic reportage and fast street photography, or if you want differently placed objects equally acceptably sharp, but for the rest it should be avoided.

[benedict297]

OP-Are you OK with these replies to your initial question?

 

Yes, so far, theres a few things which I am still confused about but I can read more on the web for that.. thanks for your reply. I went out to brick lane in London and once I get a laptop I shall post some pics so you guys and see and maybe give me more pointers.

 

Thanks

[lct]

That is especially true when shooting digitally.

Nor for me i must say. I just follow the engravings of my lenses and it does work generally. See an example here: http://tinyurl.com/q5nnlu8 (M240, Elmar 50/2.8 v2, f/8). Not the same with crop cams like the M8 though.

[250swb]

For landscape 'zone focusing' or just 'using the DOF scale' is a standard technique, but it tends to require the lens to be stopped down to f/11 or f/16 to make everything equally sharp with no discernible fall off.

 

The problems with zone focusing for 'street' photography come with the wider apertures generally used to keep shutter speed up, maybe f/5.6 or f/8. This is where I think Jaap's comments come in. It isn't a get out of jail card, it is an emergency position. I think for street photography it is better to decide what the important thing in the picture is, and focus on that, rather than risk the main event being less sharp than the litter bin in the foreground.

 

Steve

[jaapv]

Just realize that the "zone of sharpness" is an optical illusion caused by the inablility of the eye and brain of the viewer to resolve the existing unsharpness.

 

As such there are more factors that influence the phenonema.

 

For instance the amount of light the print is viewed under - like moving to a bright spot to read small print.

 

Or the interest we have in the photograph: micro-movements of the eye will scan the image allowing the brain to interpolate more detail. Thus less apparent DOF in an interesting photo.

 

A common misconception is that the "sharp zone"is an on-off effect. It is not. When details get further removed from the plane of focus they gradually get more blurry - until they reach the point that we start to notice the blurriness, which then gradually increases.

 

What is the sense of all these esoteric concepts? Not too much, forget about them, but let it leave an idea in your mind that zone focussing is the amount of unsharpness that you will accept in the final print. Just how much or how little that will be can only be learnt through experience.

And remember: an interesting photograph with some technical flaws may well still be a great photograph, but a boring image that is technically perfect wil always remain a boring image.

[Jeff S]

 

But understand that focus is optimized at one place; the rest is 'acceptably sharp,' and that depends on various factors, especially in the eyes of the beholder.

 

 

 

Consistent with Jaap's conclusion, generalized intentionally, and best determined by actual practice and printing IMO.

 

Jeff