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Old Feb 10, 2007, 3:51 PM   #11
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Marinjo wrote:
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Thanks for help! But I need some more explanationabout AiAF. When the AiAF locks with several green squares, does this meen that these objects are in the same plane (distance) from the camera and so all be in focus (as well as other objects in the same distance),orcan they be in different planes? In a small 2 dimensional LCD screen it is difficult to realize to which objects the green squares are locked! Sometimes one single green square covers another object that is by side, but can be in a different distance. And what favour one can get from this AiAF information? How to use it? What if I see that the green squares are clearly locked to objects within different distances?

Great thanks, Badeye!
I think that Badeye explained AiAF quite well. The more green frames the better. It doesn't imply that the entire area covered by green rectangles has exactly the same distance. However, it implies that the green area is at least within DOF at wide open
aperture. Thus your observation that the green area covers different distances is correvt. In reality the DOF covers even a much wider area.
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Old Feb 11, 2007, 4:17 AM   #12
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Thanks, kassandro. That meens, that I must watchif the object, which I wish to be in focus, is in the range covered by these numerous AiAF squares, right? If this object is not directly covered by a green square, then it may be rather unconvenient to tell wether it is in focus. Possibly though it is more convenient to use the center focusmeasuring mode?!
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Old Feb 11, 2007, 10:28 AM   #13
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Exactly. if you use the center or flexizone focus system you have complete control over where the focus is and is all detailed in the user manual. However, remember that if the subject is far away, and the square is larger than it, you may find that the AF system has actually locked onto something slightly next to or behind what you were hoping to get into focus. This is why it is sometimes useful to point the camera at something that is in the same lighting conditions and the same distance away, but will be completely covered by the square. Then you simply press the shutter button down halfway and hold it there to lock the settings, and move the camera back to compose the scene. Finally you finish pressing the shutter button down all the way to take the picture. This method ensures that the focus and exposure are measured for the right distance and lighting that you want instead of what the camera decides.
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Old Feb 11, 2007, 3:39 PM   #14
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kassandro wrote:
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Show us a picture which exhibits your IQ problem. Here is a full resolution picture from my A710 IS:

That is about the best you can get from a tiny 1/2.5" sensor.
Image sensor: I have to buy a new camera because I dropped my A710. Before I dropped it, I got alot of blurred images whenever I was zoomed all the way out to 210mm optical or whenever I went past that with the digital zoom. No matter what, most of my pictures came out blurry whenever it was zoomed out. Can somebody tell me what's the point of the image stabiilizer if the majority of the pictures (when zoomed out)come out blurry? It didn't seem to help any. Maybe they need to put a dual image stabilizer in there because the single, solitary one didn't seem to do much on my camera.:-?

Anyway, now I'm looking at the A640. The A640has 10 megapixels whereas the A710 has 7. Best of all, the A640 has a 1/1.8" (7.18 x 5.32 mm) size image sensor. The A710 has a 1/2.5 " size sensor.

I'm not sure if any of this will make any difference in the long run. I can't see going back to the A710 all because of an image stabilizer that didn't seem to do anything, anyway. I had plenty of pictures that came out blurry whenever I was zoomed out with the A710, plenty. :sad:

I'd rather have the A640's bigger image sensor and more pixels for 11x17 print outs. If I have to give up the image stabilizer, so be it. I'm not here to bash the A710, I'm here to learn from others. Any of your thoughts on this would be appreciated, especially if I'm in error. :-)




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Old Feb 11, 2007, 3:43 PM   #15
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Could you post some examples of these blurry pics, and what kind of shutter speeds where you getting at full zoom in the blurry pics?
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Old Feb 11, 2007, 4:06 PM   #16
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Sintares wrote:
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Could you post some examples of these blurry pics, and what kind of shutter speeds where you getting at full zoom in the blurry pics?
I'd be happy to post some of those blurrypics up, and in fact I'm glad you suggested that. Maybe I'll learn something from this excercise. Maybe it was something I did wrong with the camera. Anyway, first I have to make a cup of coffee, so I'll be back in45 minutes (maybe less)with those blurry pictures that I was talking about, allshot while zoomed out.

Until then, here is one that was shot with the A710, though not zoomed out.


















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Old Feb 11, 2007, 4:12 PM   #17
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RanchDressing, just so that we can make sure we are talking about the same thing, what do you mean by zoomed in/out? Usually zoomed in means that someting far away is made to appear larger while zoomed out means that objects remain more or less their true size, or smaller.

From what you described I think that you were talking about problems when you were zoomed in (larger objects) is this correct?
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Old Feb 11, 2007, 4:21 PM   #18
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Badeye wrote:
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RanchDressing, just so that we can make sure we are talking about the same thing, what do you mean by zoomed in/out? Usually zoomed in means that someting far away is made to appear larger while zoomed out means that objects remain more or less their true size, or smaller.

From what you described I think that you were talking about problems when you were zoomed in (larger objects) is this correct?

Sorry, you're right, I made a mistake, a bad one. :homey:



I should have said "zoomed in." Maybe I'll go back and edit all of my posts so I don't confuse anyone. And I will be back to post all of those blurry pics that were made while zoomed in at 210mm on up. Until then, here's one that was indeed zoomed in with the digital zoom. Sorry, I don't remember the exact focal length, but it was zoomed in big time. I was far away from the 3 yellow steel poles that are about 3 feet tall and 2 or 3 inches in diameter. In the backround is the Pacific Ocean. What I wanted to do was see how sharp those yellow poles would come out.
























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Old Feb 11, 2007, 5:04 PM   #19
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With all these shots, I was:

>Using the Canon A710 IS.

>Leaning up against a sturdy light pole to helpsteady myself as much as possible.

>I shot them all in auto mode.

>They were all shot as a matter of excercise in order to learn more about the zoom capabilities of the new A710 that I had just purchased a few weeks earlier.

>All the shots were all zoomed in. I was using either the digital or the opticalzoom in these photos. Sorry, I can't remember the focal length.

>While leaning against the lightpole, I concentrated on keeping my body as still as possible.

If you have any advice, information or criticism about any of this, please postit herein this thread.




























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Old Feb 11, 2007, 5:21 PM   #20
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With all these shots, I was:

>Using the Canon A710 IS.

>Most were shot leaning up against a sturdy light pole to helpsteady myself as much as possible.

>I shot them all in auto mode.

>They were all shot as a matter of excercise in order to learn more about the zoom capabilities of the new A710 that I had just purchased a few weeks earlier.

>All the shots were all zoomed in. I was using either the digital or the opticalzoom in these photos. Sorry, I can't remember the focal length.

>While leaning against the lightpole, I concentrated on keeping my body as still as possible.

If you have any advice, information or criticism about any of this, please postit herein this thread.









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