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Old Apr 7, 2007, 10:24 PM   #1
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infinity focus

whats the opinion here of it? I suppose those single-use 35mm cameras have infinity focus as there is no focusing mechanism.

Set to it, the camera doesnt focus, thereby using less battery power. But is it worth it? Are the pics focused and properly exposed?

I really do hate to pre-focus and hold the shutter button half-way and wait for the subject to be where I want it. Also, if using f/8, it takes longer to focus, thus the moment is gone by the time you take the pic.

Also, center vs. multipoint focusing. Most pics taken using center focus are out of focus. Whats it used for anyway? I see no point in MF in P&S cameras as well. It time consuming and tedious.
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Old Apr 8, 2007, 1:02 AM   #2
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romphotog wrote:
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infinity focus

whats the opinion here of it? I suppose those single-use 35mm cameras have infinity focus as there is no focusing mechanism.

Set to it, the camera doesnt focus, thereby using less battery power. But is it worth it? Are the pics focused and properly exposed?

I really do hate to pre-focus and hold the shutter button half-way and wait for the subject to be where I want it. Also, if using f/8, it takes longer to focus, thus the moment is gone by the time you take the pic.

Also, center vs. multipoint focusing. Most pics taken using center focus are out of focus. Whats it used for anyway? I see no point in MF in P&S cameras as well. It time consuming and tedious.
Infinity focus has it's place. Many digital cameras give you the choice of setting one or more "my modes" to make getting to certain settings easier and faster. One such mode I have on my camera is infinity focus, the widest focal length which, in the case of my camera is 28mm wide angle, aperture priority and f5.6. Those factors all give me the ability to utilize the camera in a snap shot type mode with little delay between shots, and none at all due to the camera trying to focus.I also have a second "my mode" of the same settings with one exception. I set the focus to 10 feet to makecapturing closer images faster.

You say using center point focusingis not as accurate as multi-point focusing systems. That would only be because you don't use it correctly. Most multi-point focusing systems will lock onto the closest object, which may or may not be the actual subject you are shooting. I like using center point focusing because I want to be the one deciding what the camera's going to focus on. I'll press the shutter release half-way down to lock focus, recompose to how I want the image to look, and shoot. I agree there are times when multipoint or expanded field AFmay bebetter... mainly in low light conditions where you may or may not point the camera at something with enough contrast to allow your camera to focus correctly

Depending on the focal length used, infinity is more or less useful. To get the most use of it, you really need to be usinga wider focal length since depth of field shrinks as you zoom to longer focal lengths. By the time you get to the maximum telephoto setting of your camera, the only thing that will be in focus may only be something atinfinity, or at least something a long way away.

Manual focus on small digicams with toggle switches and on what are sometimes grainy, low resolution electronic viewfinders is often a useless feature. On that I will heartily agree. Being able to set infinity focus is the main advantage and, to be honest, on the more advanced models Ithink thereshould bea button or option to reassign a button on the camera to simply press and the lens would eitherset itselfto infinity or lock itself to the currently focused on distance so you don't have to focus and then wait with the release pressed down halfway....that is a pain..
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Old Apr 8, 2007, 10:16 AM   #3
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Greg Chappell wrote:
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or lock itself to the currently focused on distance so you don't have to focus and then wait with the release pressed down halfway....that is a pain..
that feature is on a few cameras, such as the Kodak P850.
I have used it several times, and _always_ get out of focus shots.
It simply did not lock focus on the subject.

If you have the time, MF might do the trick.
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Old Apr 8, 2007, 7:54 PM   #4
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On Kodak cameras the Infinity focus function, whether accessed as a seperate button or from the mode dial does one thing and one thing only. It focuses the lens at infinity regardless of focal length. The purpose of this function is for caseswere the scene has near objects and far objects and the far objects are the most important. It avoid the auto-focus from focusing on the near objects at the expense of the more important distant object. You MIGHT encounter such a situation when using natural framing.

Infinity focus is different from hyperfocal focus. Hyperfocal focus is focusing the lens at that distancecloser than infinity where, atthe selectedaperture distant (infinity) objects are still within the depth of field.

I have no idea what other brands of cameras do with that function if they have it.
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