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For those of you who are new to the whole camera scene, or perhaps you're just new to the digital scene, this article may help you find what you seek. A lot of this will fit other brands of cameras, but this one will be geared toward Canon gear as I shoot Canon gear and deal with Canon SLR (Single Lens Reflex) gear exclusively.
For those of you who have no idea what you're jumping into, you're starting in the right place: learning about cameras and educating yourself to make an informed decision. SLRs are cameras that allow you to see exactly what you are going to take a picture of. Have you taken a picture with a point and shoot and found that it didn't come out quite the way you wanted? This is because the viewfinder is offset from the lens. Of course, digital cameras now have the feature to preview what you're going to take a picture of and have solved this problem for the digital P&S cameras.
Digital vs. Film
The film cameras are a great place to start, they're cheap, however, you will need to deal with buying and developing film. I held out for as long as I could with film cameras (probably about 2 years too long) before I tried out my friends Canon 10D and immediately knew I *had to have* a digital camera. Instant gratification was worth abandoning my loyalty to film. This is the true beauty of a digital camera. If you take a picture you don't like, you can immediately try again. Granted you may not get the chance again, but at least you won't have to wait an hour waiting for the results to come back.
Lens Compatibility:
For the film photographer going to digital, you're in luck. Your film lenses (assuming you're shooting EOS lenses) will fit the digital cameras!
There are Canon lenses designated, EF-S (S for short back focus), are built specifically for the Digital Rebel/Rebel XT, 20D and 30D cameras.
All standard lenses (non-EF-S) fit all cameras.
Maximum aperture size, cost and quality are all directly proportional. As the maximum aperture gets bigger, the cost and quality of the lens goes up.
Camera Basics:
If you've gotten this far, you're realizing that you are either completely confused or you're reading because it's sinking in. I hope you are one of the latter. Taking pictures involves 3 different variables: aperture, shutter speed and ISO.
Aperture:
"Why would I want a large maximum aperture?" you ask? This is what allows light to get into your camera. The larger the aperture, the more light can get in, the faster the shutter speed, the more likely you will be able to get a picture without blur. A larger aperture allows you to take pictures of the subject and have things in the back and foreground blurred. This is normally used for taking portraits. A smaller aperture allows more things in the back and foreground to be in focus for use in scenery and landscapes. Aperture is indirectly proportional to the numerical number assigned. The number assigned is called an F-stop. A small numerical F-stop designates a large aperture. Changing the aperture from F2.8 to F4.0 would be decreasing the aperture by one stop (or reducing the light entering by one half). Each stop for aperture is either multiplied or divided by 1.4 from the last. F2.8 x 1.4 = F4.0 Examples: F2.8 (large), F5.6, F11(small).
Shutter Speed:
The shutter speed determines how long you expose the film/sensor to light. The longer you expose, the more light information can be stored (up to a point). This is usually measured in fractions of a second. The rule of thumb is a lens at a particular focal length, let's say 80mm, will need a shutter speed of the inverse of that number, in this case 1/80th of a second to avoid camera shake. The faster the shutter speed, the more likely the picture you take will stop the motion that is occuring. You would want fast shutter speeds to be able take a clear picture of a person running. Moving the shutter speed from 1/60th to 1/30th doubles the exposure time. This would be called increasing the shutter speed by one stop (or doubling the amount of light let in). Examples: 1/60th, 1/90th, 1/500th.
ISO:
The ISO determines how sensitive the media is to light. This goes back to film where film had an ISO rating. The higher the ISO rating, the more sensitive the film was to light. A digital sensor actually does not change how sensitive it is to light but it does take the information it gathers and amplifies or extrapolates the information to compensate for the ISO setting. The higher the ISO number, the more noisy or "grainy" your pictures will look. Many modern cameras are able to reduce the amount of noise you see, however, the lower the ISO setting the better. Changing the ISO from 100 to 200 would be increasing the ISO by one stop (or reducing the "sensitivity" by half). Examples: 100, 400, 800
So how do they all work together? Each has it's own advantage as I've mentioned in each section. Each can be used for exposure compensation. To keep the same exposure, you can change each of these to compensate for the other depending on the desired outcome of the picture. If your settings are 1/500th and F2.8 and you want to go to a slower shutter speed, you could go to 1/250th and F4.0 or 1/125th and F5.6, etc. As mentioned before one stop will either double or half whatever your previous setting is. Two stops will give you 4 times or one quarter. There are also 1/2 stops and 1/3 stops depending on how your camera is set up.
Lenses are important. Get a good lens and you'll keep it forever. Get a good camera and you will leave it for the next greatest camera that comes out. If you have money to spend, spend a little more on the lens and get an average camera, not the other way around.
SLRs will get you so many different choices that many people would rather stick with a point and shoot. They definitely have their niche in portable and convienent picture taking, however, SLRs give you the chance to really maximize the creative side of picture taking and bring a whole new dimension.
If you are looking for good lenses for relatively cheap, please check out my other buying guide.
If this article has helped you, please click "Yes" below.
For those of you who have no idea what you're jumping into, you're starting in the right place: learning about cameras and educating yourself to make an informed decision. SLRs are cameras that allow you to see exactly what you are going to take a picture of. Have you taken a picture with a point and shoot and found that it didn't come out quite the way you wanted? This is because the viewfinder is offset from the lens. Of course, digital cameras now have the feature to preview what you're going to take a picture of and have solved this problem for the digital P&S cameras.
Digital vs. Film
The film cameras are a great place to start, they're cheap, however, you will need to deal with buying and developing film. I held out for as long as I could with film cameras (probably about 2 years too long) before I tried out my friends Canon 10D and immediately knew I *had to have* a digital camera. Instant gratification was worth abandoning my loyalty to film. This is the true beauty of a digital camera. If you take a picture you don't like, you can immediately try again. Granted you may not get the chance again, but at least you won't have to wait an hour waiting for the results to come back.
Lens Compatibility:
For the film photographer going to digital, you're in luck. Your film lenses (assuming you're shooting EOS lenses) will fit the digital cameras!
There are Canon lenses designated, EF-S (S for short back focus), are built specifically for the Digital Rebel/Rebel XT, 20D and 30D cameras.
All standard lenses (non-EF-S) fit all cameras.
Maximum aperture size, cost and quality are all directly proportional. As the maximum aperture gets bigger, the cost and quality of the lens goes up.
Camera Basics:
If you've gotten this far, you're realizing that you are either completely confused or you're reading because it's sinking in. I hope you are one of the latter. Taking pictures involves 3 different variables: aperture, shutter speed and ISO.
Aperture:
"Why would I want a large maximum aperture?" you ask? This is what allows light to get into your camera. The larger the aperture, the more light can get in, the faster the shutter speed, the more likely you will be able to get a picture without blur. A larger aperture allows you to take pictures of the subject and have things in the back and foreground blurred. This is normally used for taking portraits. A smaller aperture allows more things in the back and foreground to be in focus for use in scenery and landscapes. Aperture is indirectly proportional to the numerical number assigned. The number assigned is called an F-stop. A small numerical F-stop designates a large aperture. Changing the aperture from F2.8 to F4.0 would be decreasing the aperture by one stop (or reducing the light entering by one half). Each stop for aperture is either multiplied or divided by 1.4 from the last. F2.8 x 1.4 = F4.0 Examples: F2.8 (large), F5.6, F11(small).
Shutter Speed:
The shutter speed determines how long you expose the film/sensor to light. The longer you expose, the more light information can be stored (up to a point). This is usually measured in fractions of a second. The rule of thumb is a lens at a particular focal length, let's say 80mm, will need a shutter speed of the inverse of that number, in this case 1/80th of a second to avoid camera shake. The faster the shutter speed, the more likely the picture you take will stop the motion that is occuring. You would want fast shutter speeds to be able take a clear picture of a person running. Moving the shutter speed from 1/60th to 1/30th doubles the exposure time. This would be called increasing the shutter speed by one stop (or doubling the amount of light let in). Examples: 1/60th, 1/90th, 1/500th.
ISO:
The ISO determines how sensitive the media is to light. This goes back to film where film had an ISO rating. The higher the ISO rating, the more sensitive the film was to light. A digital sensor actually does not change how sensitive it is to light but it does take the information it gathers and amplifies or extrapolates the information to compensate for the ISO setting. The higher the ISO number, the more noisy or "grainy" your pictures will look. Many modern cameras are able to reduce the amount of noise you see, however, the lower the ISO setting the better. Changing the ISO from 100 to 200 would be increasing the ISO by one stop (or reducing the "sensitivity" by half). Examples: 100, 400, 800
So how do they all work together? Each has it's own advantage as I've mentioned in each section. Each can be used for exposure compensation. To keep the same exposure, you can change each of these to compensate for the other depending on the desired outcome of the picture. If your settings are 1/500th and F2.8 and you want to go to a slower shutter speed, you could go to 1/250th and F4.0 or 1/125th and F5.6, etc. As mentioned before one stop will either double or half whatever your previous setting is. Two stops will give you 4 times or one quarter. There are also 1/2 stops and 1/3 stops depending on how your camera is set up.
Lenses are important. Get a good lens and you'll keep it forever. Get a good camera and you will leave it for the next greatest camera that comes out. If you have money to spend, spend a little more on the lens and get an average camera, not the other way around.
SLRs will get you so many different choices that many people would rather stick with a point and shoot. They definitely have their niche in portable and convienent picture taking, however, SLRs give you the chance to really maximize the creative side of picture taking and bring a whole new dimension.
If you are looking for good lenses for relatively cheap, please check out my other buying guide.
If this article has helped you, please click "Yes" below.
Guide created: 01/02/07 (updated 02/14/09)
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