ISO is the measurement of the camera's sensor/film sensitivity to light. It is one of the 3 ways to create a well exposed image (The other two being Aperture and Shutter Speed). Typically, a higher ISO for a correctly exposed image will result in the image being more noisy/grainy.
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What is “ISO” on a digital camera?
What is "ISO" in general, and how is the scale defined?
How does the ISO scale for film speed differ from ISO sensitivity as used in digital cameras?
Is lower ISO always better?
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How is ISO implemented in digital cameras?
If I change the ISO settings on my camera, obviously the gain of the system is increased, amplifying the signal from the sensor. What's not clear to me is where the amplification takes place. I see ...
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Is high ISO useful for photography?
I started photography sometime back, and always wondered when is high ISO handy in photography? Also can it be used to get any special effect in pictures?
My camera has Max ISO of 800 but I see some ...
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What does “expanded ISO” mean?
The ISO specification for the Canon EOS 7D reads as follows:
High ISO
For handheld shooting in low light, the EOS 7D offers ISO
speeds of up to 6400. Expandable to
ISO 12800, for low light ...
18
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What is exposure compensation?
What does exposure compensation do?
If I take a photo with a given shutter speed, aperature, and ISO, and then take the same shot with +1EV or -1EV, what is actually happening?
Is this just a gain ...
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What megapixel value is equivalent to which ISO film?
Is there some kind of equivalency table or formula that expresses what kind of pixels you need in a digital camera to have roughly the same quality as a particular ISO graded film? What other ...
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What is the quantative relation between flash guide number and ISO?
I found that formula on the Internet:
Guide Number = (Shooting Distance * Aperture) รท ISO Sensitivity
Is it correct? If it is could someone please explain why ISO is related to guide number in this ...
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How can I reduce the noise present when taking pictures without lowering my ISO?
I know that high ISOs tend to produce more noise, and some cameras' software can handle that noise better than others, but are there any other settings or conditions tha affect visible noise?
I'm ...
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1answer
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Is in-camera high-ISO noise reduction worthwhile?
I shoot in RAW and post-process in Aperture where needed.
Does the in-camera noise-reduction do anything that I can't do in Aperture or other post-processing software? It seems to add a bit of time ...
16
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4answers
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What is ISO and how does it affect my photos
What is the ISO setting on my camera? What does it represent? What should I be aware of with regards to ISO when taking photographs
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Why can't the ISO level on most digital cameras be set below 80?
Why is it that the ISO level on most digital cameras doesn't seem to go lower than ISO 80?
I understand (vaguely) that the sensors adjust the gain in order to achieve the equivalent of a high ISO ...
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What are the advantages and disadvantages of using auto ISO on a DSLR?
What are the advantages and disadvantages of using auto ISO on a DSLR?
Using manual ISO obviously gives you more control, but auto ISO may mean that you get "the shot" under quickly changing ...
19
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Should higher ISOs really be preferred (all other things being equal)?
My understanding of the ISO setting on digital cameras is that, unlike film-cameras, changing the ISO does not evoke any physical change in the camera. Rather, it simply tells the camera to multiply ...
6
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Does noise in images depend upon “Megapixels” or “ISO”?
I have a question about image quality. Does noise in an image is depends upon "Megapixels" or on "ISO"?
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3answers
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Where do ISO numbers come from?
I understand how an ISO number affects the film sensitivity or a digital image, but I'm curious where did the numbers come from? How come we talk about ISO 100, 200, 400, and so on instead of ISO 1, ...
5
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Why isn't expanded ISO settings (L / ISO50) enabled on Canon DSLR's by default?
It bothers me a bit when I have to hunt through menus to find the 'enable expanded ISO settings' setting in my 5D mkIII.
I'd like to know why the low ISO's are disabled however and if there is any ...
4
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4answers
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Are there any situations in which it makes sense to raise the ISO in bright daylight?
Are there any situations in which it makes sense to raise the ISO in bright day light?
For example, this pic has been taken in bright day light with ISO 3200, f18, 1/1250: ...
3
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2answers
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Assuming a perfect sensor, what is the physical limit of ISO/pixel area?
Assuming that camera manufacturers can eventually make the perfect sensor that introduces no electrical noise to the signal, at what point (measured in ISO/area of a pixel) will shot noise be so ...
13
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What are the pros/cons of the high-ISO noise reduction feature on D90?
So my D90 offers "High-ISO Noise Reduction". Sounds like a good thing, but obviously there must be a cost of some kind. The settings are "Off", "Low", "Normal", and "High", and the default is ...
9
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4answers
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Why is sensor sensitivity called “ISO”?
I was curious to know how the term "ISO" was coined for referring the image sensor's sensitivity. Is there any reason or circumstance that contributed for terming "ISO"?
Also, does ISO has a literal ...
13
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2answers
566 views
Capturing vapour or faint steam
I was trying to capture a scene that was in a dark area with a bright background. There was faint steam that I wanted to be the focus of the picture. I tried first by having a very large aperture and ...
11
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2answers
493 views
What exactly is “base ISO” and how do I find what is base ISO on my camera?
If I understood correctly, base ISO is in full stop steps from the lowest possible ISO setting on my camera. For example if the lowest setting on my camera is ISO 100, than the following table would ...
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Why shoot a daylight outdoor photo at high iso? [duplicate]
Possible Duplicate:
Are there any situations in which it makes sense to raise the ISO in bright daylight?
I was looking at this image (from From Reuters blog ...
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1answer
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Why does the camera default to ISO 400 in auto ISO mode with flash?
I've observed this behaviour on my Canon 550D, and I was wondering why it didn't use a lower or even variable ISO. I'm not sure if this is a camera/brand specific setting.
Is there any particular ...
16
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5answers
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What is the difference between digital high ISO noise and film grain?
What is the difference between digital high ISO noise and film grain? Why does one "eat detail" and the other does not?
12
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2answers
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Why is the amount of photos that fit on one card dependent on ISO?
I have a Canon 550D with a 16GB SD card. I noticed that, when in P-mode, if I choose an ISO of 100 I can shoot 595 raw files on an empty card. If I choose an ISO of 200 this is 590. And if I choose ...
12
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1answer
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What factors determine the lowest ISO for a camera?
With the introduction of the Nikon D7000, one of its advantages over the D90 is that its lowest "true" ISO is 100 instead of 200. What does this mean though, what had to change in the the ...
10
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4answers
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How does flexible ISO make shooting digital different from film?
I was thinking at the differences between SLR and DLSR (in Manual mode). In both cases you can change aperture and shutter speed as it suits you.
But with SLR you are stuck with the ISO of the film ...
9
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0answers
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What does expanded ISO mean?
Especially with regards to image quality.
I am particularly interested in when you expand to a lower ISO, say 50 rather than 100. Generally the standard high ISO is too noisy, with the expanded ISO ...
9
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3answers
471 views
Is it possible to use a lower ISO instead of ND filters?
I've seen in the CHDK page, that you can change the ISO values, and put lower ones. Now lets suppouse I want to shoot a waterfall in day, and also I want a long exposure time (10 sec. i.e.).
I know I ...
6
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4answers
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Should I prefer raising ISO or lowering the shutter speed in a low light condition?
Example:
1. A "still" object/scene.
2. Night time.
3. The only light source you have is: a tubelight on a wall.
Provided, you want sharpness all around so you won't maximize the aperture.
Flash ...
3
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7answers
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Can ISO vary on different cameras?
We all know that [ISO] + [shutter speed] + [aperture] = a great picture.
Now, let's take two different (very!) cameras: Nikon D3100 vs Nikon D800 and set them on Aperture priority.
Settings for the ...
