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Old Apr 11, 2003, 7:52 PM   #1
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Default Hyperfocal and Zone Focusing using digicams..how?

I've learned some advanced and very useful techniques using the Depth of Field Scale of the lens of my Canon AE-1 in photography class. Hyperfocal focusing allows you to obtain the maximum DOF for any selected F-stop and Zone Focusing is a method for predeterming a range of sharp focus for the photograph using the DOF scale. These two important techniques allow you greater or total creative control.

Most if not all older manual focus lens have distance and DOF scales to allow you to use both techniques. Digital cameras and newer AF lens do not have such scales. How then would one use Hyperfocal and Zone Focusing using Digital cameras and newer AF lens?

This photography class is really great.
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Old Apr 12, 2003, 7:29 AM   #2
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I know what you mean, I too used to use the DOF scales. However, I have learned to do without them with experience.

I have long given up drawing parrallels with my 35mm days.

How do you spell parallels
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Old Apr 12, 2003, 8:48 AM   #3
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There are 2 things that I do to try to approximate the hyperfocal distance. First, using the actual focal length of the lens (not the "35mm equivalent," you can look up the DOF and hyperfocal distances for several apertures and distances using a downloadable shareware program called Fcalc. If you do a Google search you'll find it. Write down a couple of settings that you're likely to use.

I shoot a lot of panos. What I usually do is to use as small an aperture as I can depending on whether I am hand-holding or using a tripod. I then focus on something about 1/3 of the way into the scene, in a landscape shot, and this usually gives satisfactory results.

If I'm shooting something much closer, I simply try to use the widest focal length and smallest aperture, and shoot 3 frames. One focused on something about 1/3 into the distance, one about 1/2, and one focused on the main subject itself.

Even though I use a DSLR now, my lenses do not have easily readable scales, but I do have the button that lets me preview DOF.
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Old Apr 12, 2003, 9:56 AM   #4
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Quote:
Digital cameras and newer AF lens do not have such scales.
jkirk who takes his Fuji 602 apart might add to this. My impression of the manual focus ring on a 602 is there's no manual connection at all. The focus ring continuously rotates and might have some sort of opto position sensor. When the cam first powers, the focus position is set, and the ring just rotates relative to the start position to drive the focus motor. So it would be impossible to put and synchronise distance markings on it. That's why the tip to find infinity, has been to rotate until the focus motor just stops, then turn it back a bit - hit and miss really!

What others have asked for, is if focus is electronic, put distance and DOF in the viewfinder display. This shows differences between fly-by-wire prosumer, and dslr cams. Actual distance range might be a challenge to get accurate, as is tracking focus with zoom, which most digicam lenses don't do well.
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Old Apr 14, 2003, 10:13 AM   #5
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The problem with defining DOF or Hyperfocal Distance is the implied value of the Circle of Confussion. There is only one distance where everything is in focus: the DOF defines the distance range that is close enough. I recall that "standard" for picking the size of the circle of confussion is an 8x10" print viewed at arm's length.

Different folks will have different ideas about how good that has to be. Beyond the personal issues, there is a big difference when shooting for the web vs. shooting for 16x20" prints.

It is very much analogous to the perpetual question, "How large a print can I make with my xMpixel camera?". As it is impossible to give one answer that will be right for everyone, it is also impossible to define the hyperfocal distance that will be right for everyone.
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Old Apr 15, 2003, 12:39 PM   #6
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Aw, there you go again with the laws of physics and light.

I never used the depth of field scale on my AE-1 that much but I sure miss doin' my own focusing through the viewfinder...it's a little more hit and miss with the autofocus and digicam.
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Old Apr 15, 2003, 4:14 PM   #7
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Quote:
Originally Posted by rych26
Aw, there you go again with the laws of physics and light.
Then I assume you want a homeopathic camera capable of producing a 500 Mpixel image using a single photon? In 16 bit color with an infinite DOF.

There is an excellent explaination of DOF at http://www.photo.net/learn/optics/dofdigital/
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Old Apr 15, 2003, 10:08 PM   #8
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Quote:
Then I assume you want a homeopathic camera capable of producing a 500 Mpixel image using a single photon? In 16 bit color with an infinite DOF.
Naw...I'd still be lacking the good vision and instinct that I crave to come up with the shot. :roll:
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Old May 19, 2003, 8:42 PM   #9
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I just found a great site on hyperfocal and digital cameras I wanted to share:
http://dfleming.ameranet.com/

There are even hyperfocal calculators for Java, Windows, and Palm.
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Old May 20, 2003, 3:23 PM   #10
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Hey, that's very interesting to play with the settings. Should be built in the cam so it comes up in the EVF. But don't you need a rangefinder? My EXIF only says 'distant view'.

The trouble with AF is you don't get feedback on my 602 of the distance measure - do you get this readout on other digicams? Perhaps if distance were included, we'd really be worrying about what the camera had decided to take as its focus point. Thanks Mike.
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