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03-06-2010, 08:28 AM   #1
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A few small questions

Fussing about in AP. Lens at f/2 in bright sunlight with K20.

Took shot. Picture actually taken at f/4 1/4000 sec according to EXIF.
Assume shutter not able to control all the light at f/2 so it automatically closed down aperture as well. Right? Assume this is a default taken by camera to protect sensor perhaps.

Assume it does the same in SP?

Another one: does camera control shutter and aperture in discrete steps or is it more or less continuously variable?

Just wondering

Last edited by wildman; 03-06-2010 at 09:00 AM.
03-06-2010, 08:36 AM   #2
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Sorry, what is AP and SP?
03-06-2010, 08:44 AM   #3
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AP=Aperture priority
SP= Shutter priority

Sorry about that...
03-06-2010, 08:50 AM   #4
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Av = Aperture priority
Tv = Shutter priority

If you are shooting Av, you control the aperture and the camera controls the shutter speed to shoot it exposed "correctly". If you stop it down, the shutter time will decrease. The iso will stay fixed at whatever setting you have selected, unless you have a range and it set to automatic iso. If that is the case, the aperture have selected stays fixed, the shutter speed and iso work together to shoot at the optimum speed and sensitivity to give you the "correct" exposure.

Tv works the same, only switch shutter speed with aperture. Other variables work accordingly.

If you want to control aperture and shutter speed in a fixed iso setting...try TAv or just shoot in Manual and you control everything... the green button works well to establish a good baseline.

If you are shooting Av and the selected shutter speed is letting in too much light, you can use exposure compensation to tweak that, granted you want to stay in Av mode.


Last edited by Jasvox; 03-07-2010 at 01:05 AM.
03-06-2010, 09:52 AM   #5
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Av = Aperture priority
Tv = Shutter priority
Sv = ISO priority

just to be more complete..
03-06-2010, 10:04 AM   #6
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In the "Custom Setting" menu, item 10 (Auto EV Compensation) must be set to "off" to avoid camera overtaking an exposure setting that can't give a correctly exposed picture.
03-06-2010, 10:08 AM   #7
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QuoteOriginally posted by jan rinze Quote
Av = Aperture priority
Tv = Shutter priority
Sv = ISO priority

just to be more complete..
This is actually it.
03-06-2010, 12:52 PM   #8
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flyer's explained it - if you don't want the camera to take over when there's too much light hitting the sensor with the current settings on a semi-automatic mode, then switch that menu option off.

A nifty feature to keep on IMO...

03-07-2010, 04:38 PM   #9
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OK. Thanks that clears it up.

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