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16 Aug 2012 8:48PM
Everyone is talking about this ISO. I dont know what it does, could someone please explain it in laymen terms, for me please. What does it do to interact with other functions? Exposure and f numbers?
Thanks in advance. Grin

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robthecamman 6 1.7k United Kingdom
16 Aug 2012 8:57PM
wat ever camera youv got read the manual
min 7 522 United Kingdom
16 Aug 2012 9:11PM
Hi Mark

this might help

Jestertheclown 9 7.7k 252 England
16 Aug 2012 9:32PM
MrGoatsmilk 9 1.5k England
16 Aug 2012 9:42PM
The way I see ISO in my minds eye so to speak is...

I think of it like a music amplifiers volume control which amplifies the music but also amplifies the background noise ( hiss in the case of music, noise in the case of a camera).

The ISO is by how much the sensor signal is amplified much like the volume control, so it amplifies the signal so that it's more sensitive to light but also amplifies the noise.

That's just how I imagine it, hope it makes sense or helps a little at least.

MrGoatsmilk 9 1.5k England
16 Aug 2012 9:44PM

Quote:Wat ever camera youv got read the manual

The manual does not always help much like text books don't always help when studying, sometimes it is better understood by seeing it from anothers view. We can all learn from a bit of discussion in the forums.
puertouk 6 1.1k 17 United Kingdom
17 Aug 2012 9:50AM
ISO was used for film and has carried on into digital. ISO gives the photographer a way of taking images which effects the shutter speed and aperture. The higher the ISO, the higher the shutter speed or the smaller the f number you can use. Using high ISO's will cause grain in your images. There is a lot of information on the web which will go more indepth on ISO, but hopefully you will grasp the basics in what I've said.
User_Removed 14 3.3k 4 United Kingdom
17 Aug 2012 10:01AM

Quote:Everyone is talking about this ISO

A lot of reviews compare cameras at high ISO. It's a weak point for many models and can be an important point for some purchasers.

A typical example is a wedding photographer in a dimly lit church who wants hand-held pictures of the ceremony without using flash. If he's already at the maximum aperture and shutter speed he can get away with and the images are still too dark he has to turn up the ISO. Some cameras produce really noisy images when you do that. The likes of the 5D MK II handle it well (and that's one reason they are very popular with wedding photographers).
User_Removed 8 4.6k 1 Scotland
17 Aug 2012 11:39AM
You may find it helpful to think of it this way:

The shutter speed (a very inaccurate term that really means the duration the shutter is open) and the aperture of the iris diaphragm are, when taken together, the two camera settings that control the amount of light reaching the sensor of a digital camera (just as they controlled the amount of light reaching the film of a film camera).

What we had in film photography was film of differing levels of sensitivity to the light reaching it. A number of different scales were used (ASA, BS, etc) but basically, a "fast" film was capable of producing a well-exposed image with less light than a "slow" film.

With digital cameras, the function with a similar purpose is the degree of amplification applied to the digital signal which the sensor produces when exposed to light. We control that degree of amplification by adjusting the "ISO" setting of the camera. (Many pundits and not a few camera manufacturers incorrectly suggest that the ISO setting alters the "sensitivity" of the sensor. This is not correct but it is a useful way of thinking about it.)

As has been mentioned above, increasing the signal amplification also increases "noise" but each new generation of digital camera tends to have become more efficient at filtering out the worst of this noise, with the result that we can now usefully employ higher ISO settings than even a few years ago. The practical result of this improvement is that we can now obtain better quality images in low light from a given exposure.

Another often-misquoted factoid is that exposure is governed by three factors - shutter speed, aperture and ISO. This is incorrect. Exposure (i.e. the amount of light reaching the sensor) is only controlled by shutter speed and aperture. ISO controls what the processing engine of the camera then does with the digital signal produced by the sensor as a result of the exposure to light.

Sometimes making the subject more complicated can make it simpler to understand.
tomcat 12 6.4k 15 United Kingdom
17 Aug 2012 7:36PM

Quote: ISO controls what the processing engine of the camera then does with the digital signal produced by the sensor as a result of the exposure to light.

A real good explanationTongue

17 Aug 2012 11:13PM
I bought my camera from a Hong kong dealer. Saving over 300 quid on the best british deal. IE no vat. Unfortunately the manual is in Japanese.
Jestertheclown 9 7.7k 252 England
18 Aug 2012 12:21AM

Quote:Unfortunately the manual is in Japanese.

You don't say what your camera is but there are downloadable Pdf. copies of manuals, in English, for just about any one on the net.
ginz04 14 281 20 United Kingdom
2 Sep 2012 4:55PM
Hi ya simply put the ISO is the cameras sensitivity to light on a very bright day you might be able to use Iso 100 but when it's dark or going dark you may have to increase the Iso to 1000 or more hope this helps
Cephus Plus
13 2.4k England
2 Sep 2012 7:38PM

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