Can someone explain Canons Metering modes to me
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Evaluative is the clever one (Nikon's matrix). It takes dozens of readings from all over the image. In that way, it not only knows what the average scene brightness is, it knows the values of the brightest and darkest tones, it knows where they are, and it knows how large an area they occupy.
It's also linked to the AF system so it knows where the main subject is (if you're on auto AF select) and how far away it is. It then interrogates this data and applies adjustments when necessary, for example if there's a large area of bright tone at the top, and a distant AF setting, chances are that's sky in landscape so it will down-weight the sky to prevent under exposure.
Evaluative will almost always get you close, if not exactly right. Good default mode.
Spot is also handy, if you know what you're doing and want to reference a particular area. Only use strictly in manual, or the exposure will be all over the place like a rabbit in a field of wet turnips.
Partial is a bigger spot - not sure what that's useful for.
Centre-weighted reads the whole image with an emphasis on the middle. In practise it's similar to evaluative, but without the smart thinking bit, so you always know where you are and the camera is less likely to do something unexpected. Sometimes favourite for more consistent E-TTL flash exposure, which can get very complicated and throw the camera's little evaluative brain into doing something silly.
At the end of the day, all metering methods are calculated guesswork. If you want the most accurate exposure, check the LCD and learn to read the histogram with blinkies enabled (highlight alert). That shows an actual recorded image, so cannot be wrong. Tweak and adjust from there.
It's also linked to the AF system so it knows where the main subject is (if you're on auto AF select) and how far away it is. It then interrogates this data and applies adjustments when necessary, for example if there's a large area of bright tone at the top, and a distant AF setting, chances are that's sky in landscape so it will down-weight the sky to prevent under exposure.
Evaluative will almost always get you close, if not exactly right. Good default mode.
Spot is also handy, if you know what you're doing and want to reference a particular area. Only use strictly in manual, or the exposure will be all over the place like a rabbit in a field of wet turnips.
Partial is a bigger spot - not sure what that's useful for.
Centre-weighted reads the whole image with an emphasis on the middle. In practise it's similar to evaluative, but without the smart thinking bit, so you always know where you are and the camera is less likely to do something unexpected. Sometimes favourite for more consistent E-TTL flash exposure, which can get very complicated and throw the camera's little evaluative brain into doing something silly.
At the end of the day, all metering methods are calculated guesswork. If you want the most accurate exposure, check the LCD and learn to read the histogram with blinkies enabled (highlight alert). That shows an actual recorded image, so cannot be wrong. Tweak and adjust from there.
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It's when the histogram has flashing red bits for those areas that are completely blown. Some of these are okay (for specular highlights) but if a lot is shown then you need to adjust your exposure downwards to reduce them, this may result in blocked up shadow areas so is not always ideal.
You should not bother with the blown areas when you have a scene with a large dynamic range and your subject is in the shadow areas, then you should expose to ensure that your subject is correctly exposed and ignore the other areas or take steps to reduce the dynamic range with the use of a graduated ND filter or take multiple images and use some form of exposure blending.
Thanks I will have a read of my manual, I do look at the Histogram to see what is happening, would be handy to see the blown bits.
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Highlight alert, aka blinkies, page 133
They flash white/black (red in some post processing software).TBH, they are my main guide to good exposure, as they are for a lot of folks. Evaluative mode always gets close, chimp the LCD and see what the blinkies are up to, adjust if necessary, shoot.
The trick is to understand the blinking bits, when to worry about them, how to tweak, and when to leave them. Guaranteed optimum exposure
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Evaluative would be the best to stick to initially, it is the most likely to give consistent results whilst you get to grip with things.
Once you have a grasp of what altering the other stuff (aperture / shutter speed / ISO) has on your images, then you can start looking at using the other metering modes.
Personally I am either using Matrix (Evaluative) or Spot.
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forget the manual it shows you were things are but not how to use them
its like the book that comes with your car, it shows were things are but not how to fix it or even how to learn to drive
magic lantern guides are good as are the digital field guides
have a look here its a good site
ive highlighted a few books for you
i can personally recomend the davd busch guides, but they are big and thick but well worth it
i now prefer his books over the others
http://www.bookdepository.co.uk/search?searchTerm=canon+eos+500d&search=search
its like the book that comes with your car, it shows were things are but not how to fix it or even how to learn to drive
magic lantern guides are good as are the digital field guides
have a look here its a good site
ive highlighted a few books for you
i can personally recomend the davd busch guides, but they are big and thick but well worth it
i now prefer his books over the others
http://www.bookdepository.co.uk/search?searchTerm=canon+eos+500d&search=search
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