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Old Aug 30, 2004, 1:20 PM   #1
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OK, so I've been getting fantastic results shooting candids with the AV setting, flash on, f8, ISO 100. I've had BAD results using the full auto option.

I'd like to understand fully why the AV-flash combo works so well. Anyone? :roll:

Thanks.



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Old Aug 30, 2004, 3:35 PM   #2
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Well, need to know a little more. You are in AV mode, and shooting flash. Do you have your custom function #3set to automatically use 1/200 sec shutter speed every shotor is the camera selecting shutter speeds to correctly account for ambient light?

I can tell you part of the reason is in full auto (at least indoors), the camera selects an f-stop of around f4, meaning depth of field is going to bemore shallowthan when you have your aperture set to f8 in AV mode, so your pictures should be sharper over a bigger area in AV mode.

Do you let the camera select the focus point in full auto and in AV? If you select the focus point in AV and allow the camera to make the selection in full auto the camera could be selecting an incorrect point to focus on when in full auto.

Get back with us regarding the points I've asked about above.
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Old Aug 30, 2004, 5:01 PM   #3
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Here's the EXIF from a great exposure outside, late afternoon. Does shed some light?

Shooting Mode
Aperture-Priority AE
Tv(Shutter Speed)
1/200
Av(Aperture Value)
8.0
Metering Mode
Evaluative
Exposure Compensation
0
ISO Speed
100
Lens
28.0 - 200.0mm
Focal Length
48.0mm
Image Size
2048x3072
Image Quality
Fine
Flash
On
Flash Type
Built-In Flash
Flash Exposure Compensation
0
Red-eye Reduction
Off
Shutter curtain sync
1st-curtain sync
White Balance
Auto
AF Mode
One-Shot AF
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Old Aug 30, 2004, 5:38 PM   #4
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OK, it does look like you have the custom function #3set to make the shutter speed 1/200 sec.The only thing the data does not show is if you have the AF set to allow the camera to pick the focus point or if you manual selectedone certain point to use, such as the middle point. If the camera is selecting the focus point in full auto, there's always the chance it will lock onto something and focus on it instead of what you want to be focusing on. That would cause some out of focus images.

F8will give you much better depth of focus. In full auto the camera selects f4, meaning a fairly shallow depth of field. You areusing f8 in AV mode plus the 1/200 sec shutter speed, whichis faster than the 1/60 the camera selects in full auto, so motion is frozen better. All of thatis contributing to what you're seeing.
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Old Sep 1, 2004, 10:39 AM   #5
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Greg,

Sorry I didn't reply sooner. Thanks for the input. I sort of understand it better now. I think I do have the focus set on the middle square. Mostly my inquiry was about the exposure not necessarily the focus and/or the depth of field.

I guess I will just have to do some tests. Thanks again.
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Old Sep 1, 2004, 11:18 AM   #6
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Alex, recognize that in AV mode, the camera exposes for available light and the flash will act as fill flash. Experiment using M mode and your flash. Try settings of 1/125 and f/8 (disregard the camera's meter telling you that you're underexposed) and let the flash control the light. I think you'll find the results a bit more to your expectations and experimenting with the settings will give you the pleasing results you're looking for. I would also recommend that you either bounce the flash or use a diffuser to prevent the harsh shadows of direct flash.
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