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Old Oct 17, 2006, 6:39 AM   #11
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romphotog wrote:
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Thus the confusion arises.
If shooting in the dark, why increase the shutter speed 4x?
Logic tells you to keep shooting at 1/30 to let more light in, not less.

Why increase ISO at all(and increase noise), when you could increase
exposure compensation instead; or use f/2.0 or f/2.8?

Ifyou are shooting moving subjects in the dark you _might_ use ISO400/800 in burst mode.
How about using a strong flash instead?


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If shooting in the dark, why increase the shutter speed 4x?
Logic tells you to keep shooting at 1/30 to let more light in, not less.
If your subject is moving - say a kid playing basketball, 1/30 is too slow of a shutter speed. That is why you want a faster shutter speed.

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Why increase ISO at all(and increase noise), when you could increase
exposure compensation instead; or use f/2.0 or f/2.8?
Exposure compensation is not magic - If you use it, the camera must change apertue or shutter speed. If your aperture is already as wide as it can go, if you want to use EC, you must do so in AV mode so the camera can change the shutter speed. As mentioned above there are times when you don't want a slow shutter speed - moving subject or just camera shake. So, the answer is - you bump up the ISO so you still get a proper exposure and the shutter speed you want.

Quote:
Ifyou are shooting moving subjects in the dark you _might_ use ISO400/800 in burst mode.
It's a bit more complicated. Typically moving subjects in low light will require ISO 1600 or 3200. And, they often require a 2.0 lens. And, depending on the movement, the use of AI-Servo mode. Then there's the question of one focus point or multiple. Again, a little more to it than just ISO 400/800 and burst mode.
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Old Oct 17, 2006, 1:14 PM   #12
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Though since the OP does not have a dslr, just a digicam, that does not have a f2 lens and does not have ISO 3200 then the discussion is a little pointless.
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Old Oct 17, 2006, 2:32 PM   #13
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Sintares wrote:
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Though since the OP does not have a dslr, just a digicam, that does not have a f2 lens and does not have ISO 3200 then the discussion is a little pointless.
Actually I disagree.

One aspect of the question is: why should I use a higher ISO. Even if the OP only has ISO 800, the points remain the same - you increase ISO so you can still keep a faster shutter speed.

As for what aperture and ISO values are required if you want to photograph moving subjects - the discussion is still on point. it brings home the fact that a digicam just may not be capable of meeting your needs. You get to a point where there is nothing more YOU as the photographer can do - you've reached the limits of your equipment.

So I disagree that it is pointless.
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Old Oct 18, 2006, 10:06 AM   #14
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romphotog wrote:
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Why increase ISO at all(and increase noise), when you could increase
exposure compensation instead; or use f/2.0 or f/2.8?
In addition to the points made by JohnG, you may want to read my response to a thread you started on August 15th.

http://www.stevesforums.com/forums/v...amp;forum_id=2

Exposure compensation is not designed to let you control shutter speeds. It's designed to make your images darker or brighter than the camera would normally take them.

That's why your images were coming out underexposed or overexposed when you used it.

Exposure Compensation is not a substitute for ISO speed settings.

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Old Oct 20, 2006, 7:23 AM   #15
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>>> Why not use a strong flash instead?

Excellent, that is, the best, idea for action shots in low light.

If you have one.

>>> Exposure compensation is not a substitute for ISO

Correct.

You use exposure compensation when the overall scene is light but you want to emphasize a dark subject, or if the overall scene is dark but you want to emphasize a light subject.

ISO, when adjustable, is always a choice you can make because higher ISO (for both film and digital cameras) generally means more grainy pictures.


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Old Oct 28, 2006, 8:07 PM   #16
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> about 2 seconds to close, what is that for?

Night-time fireworks and city lights, basically. Most cameras use this notation:

4" = four seconds
2" = 2 seconds
1" = 1 second

Below one second, it probably says "250" for 1/250 of a second and so forth.

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Old Feb 5, 2007, 4:34 AM   #17
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Hello, don't feel bad. I still call it ASA.:idea:
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Old Feb 23, 2007, 3:24 AM   #18
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kshapero wrote:
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Hello, don't feel bad. I still call it ASA.:idea:
It all depends on if you want to be American or International :roll:..... the numbers equate.

ISO=International Standards Org.
ASA=American Standards Assoc.

Or as a manufacturer just label things just one way worldwide.... why ISO has likely won out.
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Old Feb 23, 2007, 3:31 AM   #19
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JohnG wrote:
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the points remain the same - you increase ISO so you can still keep a faster shutter speed.
OR to gain more Depth of Field. (higher f/ )
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Old Feb 25, 2007, 5:39 PM   #20
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Hayward wrote:
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kshapero wrote:
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Hello, don't feel bad. I still call it ASA.:idea:
It all depends on if you want to be American or International :roll:..... the numbers equate.
Isn't ASA the old fashioned way of refering to the speed? At least for those of us here in the US.


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