Repost of No Blurry Photos Tutorial

Discussion in 'Photography 101' started by Tim, Nov 5, 2006.

  1. Tim

    Tim Administrator Staff Member

    TUTORIAL - No Blurry Photos
    First let me preface this topic by saying that there are three reasons for blurry photos - and the term "blurry photo" is usually used to mean one of the three reasons. a bit inaccurate, but "blurry photo" is often used by novices as a catch-all term.

    1. Improper focus - The focusing mechanism did not fully engage or engaged in error. Rare, but it does happen. Remember a camera is a machine or tool and is not always 100 % perfect.

    2. Camera shake - This is due to the shutter speed being too slow for the photographer to hold the camera. This usually happens at lower shutter speeds (less than 1/60 sec) but if the person is very unsteady it can creep up into higher speeds.

    3. Motion blur - The subject of the photo is moving too fast for the camera to stop the motor. Again, usually happens at lower shutter speeds but can happen at higher speed if the subject is moving very fast or is fairly close to the camera.

    To reduce the chances of getting a "blurry photo" -

    Focus
    Make sure the focus is locked in and you get your confirmation, whether it's a beep, or a light on the camera, or something in the viewfinder. Don't jump the gun and hold the camera steady.

    Use proper photography technique
    Hold the camera with two hands, using your right hand to hold the camera and press the shutter and use your left hand to hold the camera under the lens barrel if possible. This might be tough for point and shoot cameras in which case use your left hand on the bottom of the camera. NEVER HOLD THE CAMERA BY BOTH SIDES because you won't be able to hold it steady.

    Shutter speed
    To enure a sharp image, you need to make sure your shutter is fast enough to eliminate the chance of blur. A rule of thumb for shutter speed is 1/x sec, where x is the focal length. (ie. If your lens is at 135mm, you need to be 1/135sec or faster to ensure a sharp image, slightly faster is your hands are not steady, or lower if your have very steady hands).

    Remember to take into account the "crop factor". You need to know what the crop factor on your camera is and increase the shutter speed accordingly. Unless you are using a film camera or a full frame digital camera (of which there a many fewer) there will be a crop factor, also known as a focal length multiplier. in short, it increases the focal length equivalent to something higher than the actual focal length. for example, my Canon 20d has a 1.6x crop factor, meaning that a photo at 100mm has a focal length equivalent of 160mm. This is due to the fact that a 35mm film slide is 1.6 times bigger than the sensor on my camera. There are many different crop factors for all of the different cameras, some are 1.3x, 1.6x, and I had an old point and shoot that was 4.7x. I tell people all the time...KNOW YOUR EQUIPMENT! To find out what the crop factor is, try Googling the make and model of your camera with the words "crop factor" added into the search.

    To reduce the chance of motion blur (moving subject is blurry, everything else is sharp) you need to increase the shutter speed. I can't tell all of you how to do this with your particular cameras, but there are two ways to do this as long as you can adjust settings on the camera... 1. Raise the ISO (aka film speed); the higher the ISO, the faster the shutter. 2. Lower the aperture (aka f-number); the lower the f-number the faster the shutter.

    There are tradeoffs to either way of doing this...lowering the f-number will decrease the depth of field and raising the ISO will increase the noise or graininess in the image. Depth of field (DOF) refers to the amount of the photo that will be in acceptable focus; portraits where the face is in focus but the background is blurry have shallow DOF and landscape shots were everything is in focus have high DOF. Generally speaking, the "sharpest" f-number for any lens is somewhere is middle of the range. I almost always use between f8 and f11 in outdoor, bright light unless I specifically want a different depth of field.
     

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