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Old Apr 5, 2007, 4:43 PM   #21
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Sintares wrote:

Basics (very)

A correct exposure requires enough light to hit the sensor, and the camera controls this in two basic ways.

The width of the opening that lets light in ( the aperture ) and the amount of time the light is let in for ( the shutter speed )

Here is the shutter speeds your camera has

• P / A / S (Program/Aperture/Shutter modes): 4 sec to 1/4000 sec
• Manual: 30 sec to 1/4000 sec
• Bulb: up to 30 sec

If the screen shows 4" it means 4 sec, if it shows a number without the " , then its 1/number , eg 250 would mean 1/250s

Why use a fast shutter ?

To prevent handshake blur, or to freeze movement, the faster the movement, ice hockey , bike racing etc , the faster the shutter needed.

Why use a slow shutter?

Sometimes you don't have a choice in low light when flash is forbidden, and you have set the aperture the widest you can and the ISO to the highest you want to risk.

Other times you want a slower speed to show blur, ie sports shots sometimes look more interesting if you show a little motion blur. Or you could want to create the "foamy" look of a waterfall or waves hitting rocks.

Why would you ever use anything other than wide open aperture?

( nb , wide aperture = small f number eg f2.8, narrow aperture = large f number eg f11 )

Digicam lens are typically sharpest in the centre of the aperture range.

Also the widest aperture lets in the most light but gives you the shallowest depth of field.

Depth of field is the region in front of and behind the subject you are focusing on where it is acceptably in focus.

A shallow depth of field in good when you want to draw attention to a subject with everything else in front and behind out of focus eg a portrait or a cool picture of a flower where the flower is pin sharp and everything else is reduced to a creamy blur.

A deep depth of field is good when you want a lot of the image to be in focus, for example your friends a few metres in front of you and the pyramids a few hundred metres behind them !

Digicams always struggle on theshallow depth of field part as their sensors are so small compared to dslrs and thus have a really deep depth of field, though your fuji has a much bigger sensor thanmany digicams,so will not have the same amount of difficulty , though it still cannot match a dslr.

A good book such as mentioned above would be a great idea, to introduce you to the basics of photography.
Please use "the area of the orifice" not width to describe the `ole
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Old Apr 5, 2007, 4:55 PM   #22
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Can't resist a tongue in cheek reply to Hayward (I'm a Brit) - ISO is an International Standard rather than just a one country standard! Maybe the US will also go metric one day (and drive on the RIGHT, i.e., left side of the road) .

Yes, I know that we Brits still use miles like you do - but yours are longer aren't they?
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