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Old Oct 13, 2006, 4:55 PM   #1
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Can you Guy's and Gal's explain ISO to us Novice users...
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Old Oct 13, 2006, 6:21 PM   #2
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ISO is the sensitivity to light.

Basically the signal from the sensor is gained up when the ISO setting is increased.

Typically this means you can shoot in lower light without using a flash and use a higher shutter speed than you otherwise could with the lower sensitivity.

The problem increasing ISO gives, is all the noise, errors etc is also increased making the picture quality drop, ie think of listening to a faint AM radio station, turn up the volumn also turns up the hiss and static ..

Doubling the ISO will make the camera twice as responsive to light, eg if ISO 100 is giving you a shutter speed of 1/30sec, then increasing to ISO 200 would let you use 1/60s and ISO 400, 1/120s etc etc

With the Fuji 9500 you can easily use ISO 400, ISO 800 at small prints or with careful noise reduction and probably forget ISO 1600 !

So , if you can get away with it use the lowest ISO you can while still having a fast enough shutter speed to freeze motion and prevent hand shake ruining the picture, while if the shutter speed is too low then increase the ISO to compensate, but not too high or the picture will look really bad, though you can use noise reduction programs to "smooth" out or remove some noise , though that can also remove some fine details ..

The f=6.2-66.7 is the actual focal length of the lens.

Due to the small sensor it gives the field of view (in 35mm film terms) of a lens with the focal length of 28-300mm.
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Old Oct 14, 2006, 6:05 AM   #3
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So how do you adjust shutter speed on the s9500??
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Old Oct 14, 2006, 7:28 AM   #4
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Set the mode dial to S (shutter priority) use the command dial to change the shutter speed.

Another interesting mode is P Programmed Auto.

Turning the command dial changes both aperture and shutter speed in various combinations so that they equal the same exposure as the camera has metered for, this allows you to try out quickly the various combinations knowing that the end result will still be a good exposure and it only shows viable combinations.
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Old Oct 14, 2006, 6:03 PM   #5
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So whats the faster shutter speed and real slow shutter speed for??

I adjusted the shutter speed to its lowest and it took about4 seconds to close, whats this for??

Thanks for your reply!!
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Old Oct 14, 2006, 6:15 PM   #6
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On the "S" Shutter Priority. Why does it say "Using comand dial" what does the 1-4000 mean?? It also goes below that?? For Instance 2,5",3" down to 4".

Sorry if i'm a pain, but, i'm intrested in learning whatever i can,for some great shoots when i go to " Vennice" In November

I'm :?
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Old Oct 14, 2006, 6:51 PM   #7
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May I suggest a book to you? It is the "Complete Digital Photography" 3rd edition by Ben Long. It is a very in depth book on all aspects of digital photography and was very helpfull to me. Good Luck!!!!
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Old Oct 14, 2006, 9:53 PM   #8
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Ok.

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.

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Old Oct 15, 2006, 10:48 AM   #9
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Thanks guys for all your input!!!

Cheers!!!
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Old Oct 16, 2006, 6:57 PM   #10
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"Doubling the ISO will make the camera twice as responsive to light, eg if ISO 100 is giving you a shutter speed of 1/30sec, then increasing to ISO 200 would let you use 1/60s and ISO 400, 1/120s etc etc "

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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