drzenitram wrote in post #15407680
Alllllright Colby, where do we begin?!
For starters, I have to say that you've got some reading to do! The world of photography is vast and there's so much to learn that you'll never stop learning, but a good place to start is by understanding that photography is all about light. Your "
shutter speed", "
f stop(or aperture)", and "
ISO" are the trifecta that need to become second nature to you.
Forgive me if I'm telling you what you already know, but it's always good just to have a refresher.
Start by shooting in M(manual), Av(Aperture Priority), or Tv(Shutter Priority) to give you more control of your camera.
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Shutter speed-This is how long the sensor is exposed to the light coming in through your lens.
-The longer your sensor is exposed to the light, the more light it takes in(1 second<more light> vs 1/10 second<less light>

.
-Faster shutter speeds freeze movement, including camera shake(from hand movements, the mirror slapping down inside the camera, wind blowing, etc.).
-Slower shutter speeds do not freeze movement, and can result in blurry shots(and also artistic representations such as smooth water and star trails).
-Unless using a tripod or a lens with Image Stabilization(also known as IS, OS, VC, Optical Stabilization, Vibration Compensation), shutter speed should be at least 1/<focal length> to avoid camera shake. For example, if shooting with your lens set @ 200mm, use at least 1/200th shutter speed or faster, such as 1/400 or 1/1000. If shooting with your lens set to 50mm use at least 1/50 shutter speed. If shooting on a crop body(like your t2i), multiply this times the crop factor(1.6) so a 200mm lens should be shot at a minimum of 1/320 to avoid camera shake.
-Image Stabilization/OS/VC allows for a reduction in that recommended shutter speed. 2 stops of IS means that you can take that 1/320 @ 200mm and cut it in half 2 times. One stop of IS would be down to 1/160, 2 stops lowers that to 1/80th.
*Recommended shutter speeds:
*-Still objects: 1/focal length+ or IS reduced shutter speed
*-Portraits: 1/60+ for a mostly still subject
*-Sports: 1/640+ for running sports, 1/1000+ for cars/airplanes
*-Wildlife: 1/200+
*-Landscapes: Depends!
Since you want to be shooting action, you should aim for a fast shutter speed. My guess is that you were shooting at too slow a shutter speed and that resulted in blurry photos because your subject was moving too fast for the shutter speed you used.
In order to get a faster shutter speed, you can do one of three things:
1. Get more light!(Use a flash, shoot during daylight, turn on more lights)
2. Lower your
fstop(aka widen your aperture), which lets in more light because of the wider opening, if shooting at f5.6, lower your fstop to f4(which is called wide open). The reason some lenses are so expensive is because they allow for very wide apertures like f1.4(prime lenses) or f2.8(zoom lenses). Every 3 "clicks" of your aperture value is 1 stop, they go as follows(the bold are "full stops"):
1.0 1.1 1.2
1.4 1.6 1.8
2 2.2 2.5
2.8 3.2 3.5
4 4.5 5.0
5.6 6.3 7.1
8 9 10
11 13 14
16 18 20
22. One full stop widening of aperture is equal to letting in twice as much light. The change from f5.6 to f4 would allow your shutter speed to go from 1/30 to 1/60th. Usually lenses are sharper when they are "stopped down"(which means that the aperture is set narrower than "wide open"), so, while for artistic purposes you may frequently want to use lenses wide open, it's usually best to revert to #1(more light).
3. Raise your
ISO(Sensitivity of the sensor to light... sort of). If your ISO is at 100, ISO 200 will let in twice as much light(and double your shutter speed from say... 1/30 to 1/60.) From ISO 100 to ISO 1600 you would let in 16 times more light. Your shutter speed would go, for example, from 1/30 to 1/500. However, increasing ISO will introduce some noise into your photos. Sometimes this is unavoidable, but if possible it's always best to revert to #1(more light).
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For the Christmas light photos, you may want to try lowering the exposure(Ev).
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In order to blur out the bars at the zoo, you'll need to be fairly close to the bars and your subject will need to be a good distance away from the bars. You'll want to use a longer focal length(like 200mm) and a wide aperture(like f4). This will make a narrow "depth of field" that you can focus on your subject and will not include the bars.
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To take a photo of the moon I would definitely recommend using a tripod! Try different settings on your camera to see what you like, but I would recommend first trying something like ISO 100, f4, 10 second shutter speed, 200mm. Go from there!
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The focus ring is very useful. On the 70-200 f4 L you have full time manual focusing. That means that even when the lens is set to autofocus, you can still change the focus even after the autofocus has selected a target. This is useful in situations like taking pictures at the zoo where you may be trying to focus on an animal, but your camera chooses to focus on the bars or chain in front of the animal. You can then adjust the focus manually using the focus ring and still get your picture. You can also use the focus ring when the lens is set to Manual Focus.
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The 70-200 f4 L is a very capable lens, and can deliver some really incredible photos. The T2i is also a great camera, it has canon's highest quality crop(1.6) sensor, the same one used in their 7D, and can create beautiful images.
With a little practice shooting, and a bit of reading, you'll be making beautiful photos of your own in no time.
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I hope this answered some of your questions and didn't confuse you too much. Welcome to the forums, and Merry Christmas!