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Thread: New image

  1. #21
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    OK. Took four more pictures. All at aperature priorty, auto ISO. Used auto ISO just so I could get an idea what ISO the camera would select. Here are links to two of the photos. Both are untouched. The first is standard exposure, F4.0 ISO 100 at 70mm The second is the same but with the exposure bumped +1.0 There was not quite as much sun when I was shooting today. The 1.0 exposure bump definetely looks better. I thought it may be a bit over exposed but if I use auto tone in light room it actually increases the exposure more. Focus was on pine in center of shot. Clarity and lack of noise at that pine seem to be pretty good. The woods behind are pushing toward the outer edge of focus. Will go back tomorrow and shoot same shots at 200mm. Will also try with exposure bumped 1.0 and ISO forced at 100 to see what kind of shutter speeds I get.

    First Image: https://picasaweb.google.com/lh/phot...eat=directlink

    Second Image: https://picasaweb.google.com/lh/phot...eat=directlink

  2. #22
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    Bill You may have thought you were focusing on the pine, but if you look very close it appears the camera actually focused on the little tree branch in front of the pine. It was probably the closest thing and is front of the tree and the AF locked on to it.

    Snow is tough even for those who have been taking pictures a while.

  3. #23
    Senior Member clemmb's Avatar
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    Quote Originally Posted by NorthWoods Bill View Post
    Will also try with exposure bumped 1.0 and ISO forced at 100 to see what kind of shutter speeds I get.
    Also try ISO 200. Without IS the rule of thumb with a FF camera is shutter = focal length. At 200mm you will like a shutter of 1/200 or faster. I think the rule of thumb goes with crop factor. Your Rebel 1.6 crop factor will need 1/320. Someone correct me if I am wrong. Of course if your lens has IS then you can possibly go somewhere around 1/60 or 1/80.
    Mark

  4. #24
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    Quote Originally Posted by HDNitehawk View Post
    Bill You may have thought you were focusing on the pine, but if you look very close it appears the camera actually focused on the little tree branch in front of the pine. It was probably the closest thing and is front of the tree and the AF locked on to it.

    Snow is tough even for those who have been taking pictures a while.
    I am not sure I can see the difference. The branch looks a touch clearer then the line, is that why you would say that? _

  5. #25
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    Clemmb,

    It is an image stabilized lens. 70-200 F4 L IS USM

  6. #26
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    Quote Originally Posted by NorthWoods Bill View Post
    I am not sure I can see the difference. The branch looks a touch clearer then the line, is that why you would say that? _
    Looking again this morning on a larger monitor, I am not sure if it focused on the little tree. But I do know with the lens you are using that the tree you are aiming at should be sharper than it is.

    Your shutter speed was slow and it is possible you still have some camera shake as well. That said you were in AV mode, aperture priority and it is probably a good learning experience for aperture. You noticed that the woods behind were out of focus, this is because of the narrow depth of field at F/4. If you were at F/8 they would have been a bit more in focus but not really in focus well. This is the nature of lenses and the longer they get the tighter the depth of field is. When a lens gets wider the more area that will be in focus. The closer your subject the depth of field gets narrower, and as you move farther from the subject it gets deeper. If you want to experiment with this you can go here:http://www.dofmaster.com/dofjs.html
    Last edited by HDNitehawk; 02-15-2012 at 12:22 PM.

  7. #27
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    HDNitehawk,
    So if I am thinking of this correctly the only way to have increased shutter speed would have also been to increase my ISO thereby adding more potential noise, correct? So maybe I should have bumped the ISO to 200 which would have still likely resulted in acceptable noise but increased my shutter speed? I took a look at the DOF calculator (actually also have one on my phone) and acording to the online one I should have had 46' in front of the tree and 179' behind it in acceptable focus.

  8. #28
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    Bill; yes you are right you needed to raise your ISO, it is always a fight to get the speed you want and the aperture you want, then keep the ISO at a fair number. I wouldn’t worry about noise until you get past ISO800. Even at ISO1600 for the most part you should be ok but I try and avoid it if I can. With the picture you just took, I wouldn’t worry about noise much at all because of all the white snow.

    So you were about 60’ from the tree? I am still thinking camera shake. Raise your ISO to get more speed and it would have helped.

  9. #29
    Senior Member clemmb's Avatar
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    Quote Originally Posted by HDNitehawk View Post
    Bill You may have thought you were focusing on the pine, but if you look very close it appears the camera actually focused on the little tree branch in front of the pine..
    It also looks to me that your focus was on the little tree in the forground. In DPP you can see which focus point was used.
    On a 1.6 crop camera I am very comfortable with ISO up to 400. 800 is getting a little noisy but I can deal with it. Much above that it is just too noisy to me.
    Mark

  10. #30
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    Regarding Noise: Actually more in the 100 to 125' foot range. At 125', 70mm, F4 to DOF calculator shows 78' near limit, 304' far limit. When I zoom in on the pine needles of the tree in the original raw image they are not as clear as I would like them, they look just a tiny bit pixelated, maybe? I took that to be noise but now I am thinking it is lack of sharpness in the image. I have looked at a zoomed picture of a painted wall before and saw the dots caused by noise, I took what I was seeing on the tree to be the same but now I am thinking I was wrong. I will take some more shots this afternoon.

    Regarding focus: Would I have been better off limiting the AF on the camera to one point so I have complete control over what it is focusing on?

    I cant thank everyone enough for being tolerant of newbie questions and willing to take the time to help.

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