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  1. Member wingspar's Avatar
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    This subject is not covered in the manual at all. Only still image focusing is talked about in the manual. I do not use the video cam for still images.

    While recording video, I may want to hold an object close to the camera for a closeup. When I do this, most of the time, the object is totally out of focus, while everything in the background is in focus. Same if I am taping someone who is standing too close to the camera, they will be out of focus while the background is in focus. (Camera is on tripod)

    How does the auto focus of this camera work?

    There is no focus sensor in the viewfinder as there is with still cameras. Where is the camera focusing?

    Does the focus distance change depending on whether you are shooting wide angle or zoomed in, even just a little?
    Gary
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  2. Most cameras and camcorders have differet auto focus "modes". You can set them to preferentially focus on what's in the middle of the frame, a balance of the entire frame, or something in between. Check your manual.

    Another problem you may be having: the minimum focusing distance may be too far for close up work. Ie, there is a minimum distance at which the camera can focus. Any closer than that will never be in focus. That distance will vary depending on other parameters like whether you are at full zoom, full wide angle, and the current aperture setting.
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  3. aBigMeanie aedipuss's Avatar
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    it's got manual focus for shots where auto won't cut it. up near the front press the "focus" button and control focus with the wheel next to it.
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  4. Member wingspar's Avatar
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    Originally Posted by jagabo View Post
    Most cameras and camcorders have differet auto focus "modes". You can set them to preferentially focus on what's in the middle of the frame, a balance of the entire frame, or something in between. Check your manual.
    If there was anything in the manual, I wouldnít have to start a thread like this. There is zero on auto focusing while video taping, but there is for still photos. Go figure. Makes no sense to my why they would not cover the video focusing in the manual on a video camera.

    Originally Posted by jagabo View Post
    Another problem you may be having: the minimum focusing distance may be too far for close up work. Ie, there is a minimum distance at which the camera can focus. Any closer than that will never be in focus. That distance will vary depending on other parameters like whether you are at full zoom, full wide angle, and the current aperture setting.
    That is the exact information that needs to be in the manual. Itís starting to look like the only way I will find an answer to my question is to tape at different focal lengths at several fixed distances.

    Originally Posted by aedipuss View Post
    it's got manual focus for shots where auto won't cut it. up near the front press the "focus" button and control focus with the wheel next to it.
    That wonít work when there is no one behind the camera. I need auto focus to work by itself while on a tripod with no one behind the camera.
    Gary
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  5. BuskerAlley.com zoobie's Avatar
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    try setting the camera across the room and to full zoom
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    Have you played around with "Instant AF" and "Normal AF" - any difference?
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  7. Member wingspar's Avatar
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    Originally Posted by NoBuddy View Post
    Have you played around with "Instant AF" and "Normal AF" - any difference?
    Iíve never messed with I-AF and AF. I messed around with it for a few minutes in the house this morning, but the results were worthless. Couldnít seem to focus on objects 5 feet away in AF.

    Later in the day I got out, with the camera set to the default (came that way) to I-AF, and did some tests at different distances and different focal lengths. No problems. Focus seemed fine. Iím wondering if the auto focus has a hard time in low light situations. DOF seems really shallow. Unfortunately, I didnít think about trying AF out there. Had other things on my mind.

    As a sports photographer, shooting tight has been ingrained into me for years, itís hard to get away from that. Maybe I just need to shoot at the widest angle, and set the camera closer. I donít know. Sure wish the manual talked about this. Also be nice if you could see the focus point in the LCD screen like you can when shooting with a dSLR, and be able to move the focus point around. That would sure be nice. Guess Iíll just have to set a time to experiment and see what I come up with. Maybe I could use the manual to start a fire with...
    Gary
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  8. aBigMeanie aedipuss's Avatar
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    AF works through the lens and is rather slow and hunts around frequently. i-AF works off a small sensor on the front of the camera body, and i don't think it functions like a SLR focus.
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  9. Autofocus (based on the image data) always has a hard time in low light situations. It needs high contrast, sharp edges to focus.

    As aedipuss suggested, instant autofocus uses a separate sensor, and probably an infra red lamp on the camera.
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  10. Member 2Bdecided's Avatar
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    IME I-AF snaps things into focus quickly, even when zoomed in, even in low light. The HV20 is certainly one of the batter camcorders I've used for auto focusing.

    Depends on your definition of low light I suppose. On my HV20, the image is getting grainy long before the I-AF fails. The HV20 doesn't really work at all well in really low light!

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  11. Member wingspar's Avatar
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    Originally Posted by aedipuss View Post
    AF works through the lens and is rather slow and hunts around frequently. i-AF works off a small sensor on the front of the camera body, and i don't think it functions like a SLR focus.
    After reading your post, I got the manual out, and in the front of the manual is a diagram showing the I-AF sensor on the front of the camera. To the left of the lens looking at the camera. To the right of the lens if you are behind the camera. I would never have guessed it was anything but thru the lens. No way to move the focus point, thatís for sure. How does the camera decide what to focus on then? Closest priority?

    Originally Posted by jagabo View Post
    Autofocus (based on the image data) always has a hard time in low light situations. It needs high contrast, sharp edges to focus.
    Originally Posted by 2Bdecided View Post
    IME I-AF snaps things into focus quickly, even when zoomed in, even in low light. The HV20 is certainly one of the batter camcorders I've used for auto focusing.

    Depends on your definition of low light I suppose. On my HV20, the image is getting grainy long before the I-AF fails. The HV20 doesn't really work at all well in really low light!
    Low light in this case is around 4:45 in the afternoon, well after the sun set, but not really dark yet. If I held an object in front of the camera, it would just be a blur, but when I did it in daylight, it was in focus. I was beginning to think that it was a low light situation as far as the focus went. Even on cloudy overcast days with plenty of light, I get this problem. Also, the camera seems to have a very shallow DOF for things within 10 feet of the camera, which will end up with part of the subject in focus, and part out of focus. I saw this in bright sunlight yesterday.

    This is an HV30, but operation is probably the same as the HV20.

    I think if this was a $20,000 pro camcorder, Iíd find it easier to operate. I can take any dSLR, and be at home instantly, but hand me a point and shoot, and Iíll be tearing my hair out trying to figure out how to do some things.
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  12. Originally Posted by wingspar View Post
    Low light in this case is around 4:45 in the afternoon, well after the sun set, but not really dark yet. If I held an object in front of the camera, it would just be a blur, but when I did it in daylight, it was in focus. I was beginning to think that it was a low light situation as far as the focus went. Even on cloudy overcast days with plenty of light, I get this problem.
    That doesn't sound normal.
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  13. aBigMeanie aedipuss's Avatar
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    do you have anything on the front of the cam that might block the i-AF sensor? lens hood? lens adapter? the 20k pro cam would only be easier in manual focus because of the more familiar focus ring. the little wheel takes practice and getting used to.
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  14. Member 2Bdecided's Avatar
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    Originally Posted by wingspar View Post
    I can take any dSLR, and be at home instantly
    If you're used to SLRs, it's bizarre that you think an HV30 has a shallow depth of focus! You only get anything approaching typical SLR DOF effects when you zoom in on a somewhat distant object.

    Low light in this case is around 4:45 in the afternoon
    that's not really meaningful on an international forum!!!!

    well after the sun set, but not really dark yet.
    in which case I wouldn't expect an HV30 to work well at all. Or any consumer camcorder. They don't work without light.

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  15. Member wingspar's Avatar
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    Originally Posted by aedipuss View Post
    do you have anything on the front of the cam that might block the i-AF sensor? lens hood? lens adapter?
    No. Do lens hoods and lens adapters tend to block the focus sensor? I am considering a hood and wide angle lens, but if they block the focus sensor in anyway, I see no reason to waste my money on them

    Originally Posted by 2Bdecided View Post
    If you're used to SLRs, it's bizarre that you think an HV30 has a shallow depth of focus! You only get anything approaching typical SLR DOF effects when you zoom in on a somewhat distant object.
    I did two videos with me in front of the camera at an angle with my hands extended. In one of the videos, my hands were out of focus, but I was in focus. In the next video, my hands were in focus, and I was out of focus. Itís something I donít see till I see the video on the computer monitor at home, and it makes the video useless.

    Originally Posted by 2Bdecided View Post
    in which case I wouldn't expect an HV30 to work well at all. Or any consumer camcorder. They don't work without light.
    I didnít think it was That dark, but I guess it was.
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  16. aBigMeanie aedipuss's Avatar
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    most hoods and adapters will block the i-AF sensor. looking from the front of the cam it's on the left side of the body next to the lens under the aux light/flash.
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  17. Member wingspar's Avatar
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    I now know where the sensor is. So adapters block the I-AF sensor? What good are the adapters then?

    The hood I was thinking about is the Fotodiox 43mm Square Hood.
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  18. aBigMeanie aedipuss's Avatar
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    i wouldn't use a hood if you plan on shooting sports or any vids with movement. without the i-AF sensor working perfectly the cam defaults to AF and it then does a poor job on action scenes.
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  19. Member wingspar's Avatar
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    Ok. Iíll have to re-evaluate a hood, but I see the price of the hood has gone from $17.95 last year to $7.95 now. Still, if it interferes with the I-AF sensor, Iíll pass on the hood.

    Thanks for the help. Iíve learned a lot about my cam in this thread, and if I ever buy another cam, it will have to I-AF thru the lens.
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  20. Member wingspar's Avatar
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    Duplicate Post.
    Last edited by wingspar; 13th Jan 2011 at 13:02. Reason: Site is deathly slow, causing me to post twice not knowing if the first one posted.
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