zone focusing-please explain...

Hi,

 

I've seen 'zone focusing' mentioned here a few times. Could someone please

explain what it is, exactly/

I'm guessing you select a depth of field of x feet using the distance gauge and

aperture. Are there any tricks to it, or is it as simple as that/

cheers

It really is as simple as that, James.

 

I use it all the time with a 35mm lens on an old Leica. I set the aperture to f8, place the infinity index against the '8' on the distant side of the depth of field mark and vary the exposure using the shutter speed as required. Given a sufficiently steady hand, everything from 2 metres to infinity is acceptably sharp. I use the same technique with a 50mm some of the time but for any longer lens than that, the process becomes progressively less rewarding.

 

Note the 'acceptably' though. The lenses we use for general photography only have a single plane of sharpness, so, in using depth of field, we're trading off convenience against some small loss of overall sharpness. The main subject may or may not be perfectly in focus but we're balancing that with an image that meets our needs in terms of apparent sharpness and speed of use.<div></div>

Yes, it's that simple, and I've been using it when appropriate for over 40 years. However, it may not produce the intended results, especially if you are used to using wide open apertures to create photos which really highlight the subject and relegate everything else into the foreground or background. Also, often, your lens has a sweet spot, aperture-wise, at which the lens shows off its best performance. Unless you're using that sweet spot, you should expect some degree of fall-off. Those are the tradeoffs I've most noticed over the years. BTW, the old Brownie cameras, which millions of people used to generate several generations of snapshots relied on zone focus, as they did not provide a means to focus the lens...a true point 'n shoot.

Some possibly helpful pictures, illustrating lens markings, etc., are <a href=http://www.dofmaster.com/hyperfocal.html>found on this page</a>, if you scroll down.

Zone focusing is a little more iffy for me since I often work from a zone from 1 foot to 6 feet.

The depth of field is much less proportionally. My zone focusing, because I often shoot very

fast, is often prayer; as in please let that one be in focus. My priority is in getting the timing

right than in technical details. I lose a few great shots this way but get most of them.

Don't forget the other use for this: it can be a very effective way to catch ultra-fast moving

subjects or others that would be difficult to capture with autofocus or manual focus.

 

For example, let's say I knew a subject was going to bolt through a door in a few

moments. Instead of switching to autofocus and hoping my system is fast enough, or my

manual focus chops are up to the task, I would note about where the subject would be,

manually focus on that and then let my additional depth-of-focus give me margin for

error. The door opens, I start firing away, and the subject should be in focus throughout

my pre-planned shooting zone....

 

Of course, using a wide angle lens in bright daylight also and setting up for zone focus

often gives us a sort of "infinite" focus -- we can walk the streets knowing everything from

a meter out to infinity should be acceptably sharp and then can concentrate on framing,

concentration and timing rather than focus....

Thanks everyone,

 

my question has been well and truly answered-and some. I've just got to pop my new 24mm on and go downtown for some practice...

I shoot in very busy streets where everything happens so fast there is hardly time to react and frame let alone focus.

 

I set the focus to 8ft which at f/8 gets me everything between 6.5ft to 10ft in focus with my 50mm. I don't understand why people set the lens to hyperfocal - it's just wasting dof.

"I don't understand why people set the lens to hyperfocal - it's just wasting dof."

 

it's only a waste if you don't want the background sharp. with even a moderate wide angle

lens like a 35 you get a lot at f/11 - 5.5ft to infinity. at f/16 it's even more - about 3.5

feet to infinity. and with a wider lens it's even further. i use hyperfocal when it's the

entire scene that i want. if i just want one piece of it or if things are not happenning so

quickly, i just focus on what i want. for me, presetting my focus and exposure is all about

being able to turn that part of my brain off so that i can just react.

Why not buy Ansel Adams's book on the Zone System? Its cheap, fun to read and can be easily found.

The zone system and zone focusing are two different things.

That is definitely true.

Here you go: Its NOT digital, ISBN 0-8212-0716-4 (It doesn't matter). Good reading, very high quality enameled paper. Even smells very good like an expensive book.

http://www.bookfinder.com/dir/i/Camera_and_Lens-The_Creative_Approach_Studio,_Laboratory,_and_Operation/0821207164/

James,

 

Visit <a href="www.trenholm.org/hmmerk">this website by Harold M. Merklinger</a> and click on the 'about the ins and outs of focus' link. This will provide you with all the information you are looking for (and more).

 

regards,

Juergen

Sorry, link doesn't work, its www.trenholm.org/hmmerk and click on the 'about the ins and outs of focus' link.

thanks guys, actually just discovered DOF preview function on my camera...it's certainly helped me understand apertures. Zone system I'm familiar with, but really need to revisit it, thanks. My goal is to think more and shoot less. Exposure is definitely something I can improve on, especially as I'd like to try a little velvia, which is not cheap in New Zealand.