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  1. #1
    Join Date
    Jul 2005
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    51

    megapixel vs zoom

    I am looking into getting a new digital camera. I can not afford a SLR. I notice you either get one with a high megapixel and a smaller optical zoom or one with a good zoom, but lower megapixels. Like I seen one with a 12 megapixels, but only a 5X optical zoom, but than another that had a 7.1 megapixels with a 12X optical zoom. Both were by the same company and about the same price. So which overall is better? I take a lot of sports pictures of my daughters. I want the clearest pictures, but also like to zoom in. I was thinking that maybe I should go with the higher megapixel than I can always crop or blow up the picture later. Any ideas on which way to go?

  2. #2
    Join Date
    Mar 2007
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    Bay Area, California
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    All megapixels mean is the higher the number if MP the larger your able to print. Its not a matter of image quality. If your not looking for huge prints then pay the MP no mind and focus on cameras that have more optical zoom. what cameras are you looking at? 7.1MP and 12x zoom sound pretty good. With 7.1MP you could get great sized prints if you wanted.
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  3. #3
    Join Date
    Mar 2007
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    2,132
    By huge, he means greater than 8x10.

    6mp is plenty for 8x10. It is simply the size of the image. Think pixels...mega means million. It is simply length x width.
    Nikon D300 | Tamron 17-50mm f/2.8 | Nikkor AF-S 70-300mm VR | Nikkor AF 35mm f/2 D | SB-600 | Lowepro Voyager C | Lowepro Slingshot 300 AW

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  4. #4
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    Jul 2005
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    51
    I just started looking, but the Kodak Z 712 IS has the 7.1 megapixels with the 12x optical zoom and also has an optical image stabilizer for about $300.00. I never used a digital camera from Kodak before. I now have an Olympus C-770. That has a 10x zoom with 4 megapixels, but no IS and a lot of my pictures become blurry, especially indoor and sports. I am not always the steadiest and in most situations a tripod is hard to use. I always thought the more pixels the better the quality of the pictures. Thanks for clearing that up for me. I would probably never get bigger than an 8x10. I am more concerned about the quality and clarity of the pictures.

  5. #5
    Join Date
    Mar 2007
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    2,132

    Lightbulb

    For that same price, I'd recommend you take a look at Canon's offering...

    http://www.dcresource.com/reviews/ca...il.php?cam=845

    http://www.newegg.com/Product/Produc...82E16830120043


    Nikon D300 | Tamron 17-50mm f/2.8 | Nikkor AF-S 70-300mm VR | Nikkor AF 35mm f/2 D | SB-600 | Lowepro Voyager C | Lowepro Slingshot 300 AW

    For Sale:
    Nikkor AF 35mm f/2 D - Like New (FX compatible)

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    Nikkor AF-S 17-55 f/2.8
    Nikkor AF-S 70-200 f/4 VRII
    Tokina AF 11-16 f/2.8
    SB-900 (2)
    Umbrellas
    New Tripod

  6. #6
    Join Date
    Apr 2006
    Location
    Exeter, UK
    Posts
    883
    Ken, there are 3 possible reasons for some of your pictures to be blurry. The first is if the camera hasn't focussed properly - most cameras take a little longer to automatically focus at full zoom, particularly if there's less light. You can help get round this by either pre-focussing, half pressing the shutter button for a second or two before you actually take the shot, or by selecting the continuous focus mode if the camera has one.

    The other forms of blur tend to occur when shooting in low light because the shutter has to open for a longer time to let enough light in for a correct exposure. This can lead to two related problems: the first, known as camera shake, is because it's impossible to hold the camera perfectly steady, especially in the excitement of sports action. (A general rule is that you need a shutter speed of at least 1/the effective focal length of the lens, so at 50mm equivalent, you need 1/50s or faster, but at 300mm you need at least 1/300s. This is only a rough guide, and varies between people and how excited they are - you can get better with practice). Image stabilisation can be very helpful with this problem, often allowing you to use speeds 2 - 3 stops (4 - 8 times) slower.

    The other problem is known as motion blur, and is a result of the subject moving while the shutter is open. For a fast moving sports player, you might need a shutter speed of at least 1/500s to avoid this, and motorsport can need to be even faster (though sometimes, a bit of motion blur can be quite artistic, giving a feel of speed to the picture). However, IS is no help here, you have to have the fast shutter speed, and if the light is low, the only way to get that is to boost the ISO sensitivity, which in many cameras leads to noise - speccles of "wrong" colour over the picture. Some cameras, particularly the Fuji S6000, have less noise at high ISO than others (partly due to having fewer (6M) pixels. Faster shutter speeds also help with camera shake, as described above.

    So have a look back at your pictures. If it looks as though the problem is camera shake (all the picture is blurry, possibly with streaks in one direction) then get a camera with IS - the Canon S3 or S5 would be good, maybe the Kodak Z712 (though I don't know much about that) or perhaps even the Panasonic FZ8. However, if the bluriness
    seems to be motion blur (just the moving parts, e.g. the sports players are blurry, but the background is sharp) then the Fuji S6000 might be a better camera for you.

    If parts of the picture are blurry, and parts sharp, but it doesn't seem related to what's moving, then that could be a focussing problem, and you should try prefocussing or use continuous autofocus.

    Oh, and more megapixels never make up for more zoom - you would need 4x as many pixels to crop to the same resolution as a 2x increase in focal length, which would make each pixel 1/4 the area, so noise would be a problem at 2 stops lower ISO (actually probably worse than this in practice).

  7. #7
    Join Date
    Jul 2005
    Posts
    51
    Quote Originally Posted by AlexMonro View Post
    Ken, there are 3 possible reasons for some of your pictures to be blurry. The first is if the camera hasn't focussed properly - most cameras take a little longer to automatically focus at full zoom, particularly if there's less light. You can help get round this by either pre-focussing, half pressing the shutter button for a second or two before you actually take the shot, or by selecting the continuous focus mode if the camera has one.

    The other forms of blur tend to occur when shooting in low light because the shutter has to open for a longer time to let enough light in for a correct exposure. This can lead to two related problems: the first, known as camera shake, is because it's impossible to hold the camera perfectly steady, especially in the excitement of sports action. (A general rule is that you need a shutter speed of at least 1/the effective focal length of the lens, so at 50mm equivalent, you need 1/50s or faster, but at 300mm you need at least 1/300s. This is only a rough guide, and varies between people and how excited they are - you can get better with practice). Image stabilisation can be very helpful with this problem, often allowing you to use speeds 2 - 3 stops (4 - 8 times) slower.

    The other problem is known as motion blur, and is a result of the subject moving while the shutter is open. For a fast moving sports player, you might need a shutter speed of at least 1/500s to avoid this, and motorsport can need to be even faster (though sometimes, a bit of motion blur can be quite artistic, giving a feel of speed to the picture). However, IS is no help here, you have to have the fast shutter speed, and if the light is low, the only way to get that is to boost the ISO sensitivity, which in many cameras leads to noise - speccles of "wrong" colour over the picture. Some cameras, particularly the Fuji S6000, have less noise at high ISO than others (partly due to having fewer (6M) pixels. Faster shutter speeds also help with camera shake, as described above.

    So have a look back at your pictures. If it looks as though the problem is camera shake (all the picture is blurry, possibly with streaks in one direction) then get a camera with IS - the Canon S3 or S5 would be good, maybe the Kodak Z712 (though I don't know much about that) or perhaps even the Panasonic FZ8. However, if the bluriness
    seems to be motion blur (just the moving parts, e.g. the sports players are blurry, but the background is sharp) then the Fuji S6000 might be a better camera for you.

    If parts of the picture are blurry, and parts sharp, but it doesn't seem related to what's moving, then that could be a focussing problem, and you should try prefocussing or use continuous autofocus.

    Oh, and more megapixels never make up for more zoom - you would need 4x as many pixels to crop to the same resolution as a 2x increase in focal length, which would make each pixel 1/4 the area, so noise would be a problem at 2 stops lower ISO (actually probably worse than this in practice).
    I went through some of my sport shots I noticed the players are more blurry with streaks sometimes in one direction, but basically the whole picture is not sharp. these were pictures of my daughter playing basketball in a gym.

    I also had anther question. You mentioned with the Fuji S6000 the pictures had less noise with the higher ISO, partly dues to the lower megapixels (6mp). So is it that the lower the mp the camera has the less noise you will usually get when using a higher ISO?

  8. #8
    Join Date
    Jul 2004
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    4,173
    Quote Originally Posted by ken212 View Post
    You mentioned with the Fuji S6000 the pictures had less noise with the higher ISO, partly dues to the lower megapixels (6mp). So is it that the lower the mp the camera has the less noise you will usually get when using a higher ISO?
    The Fuji cameras have a sensor that is much better at high ISO then other cameras. It's not really related to the number of MP.

  9. #9
    Join Date
    Apr 2006
    Location
    Exeter, UK
    Posts
    883
    Well, I did say partly! The physical size of each photodiode site is important, which depends on the size of the sensor and the number of pixels. Other considerations are the design of the camera electronics and the image processing (though excessive noise reduction image processing can lead to smearing of detail, as seen on some newer Panasonics).

    The Fuji S6000 has fewer pixels, (6 instead of 8 or 10), a larger sensor (1/1.7" instead of 1/1.8" or 1/2.5"), and Fuji's unique octagonal sensor layout. So it's not surprising it has the best noise performance of any ultrazoom.

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