Questions tagged [iso]

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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129
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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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What is the relationship between ISO, aperture, and shutter speed?

I know digital cameras have ISO options, and that ISO is the camera's sensitivity to light, but if you set higher ISO then you can get a noisy image. I also know there are two other camera options, ...
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Is it really better to shoot at full-stop ISOs?

The second half of this answer says Notice that I only shot full-stop ISO which is important with Canon DSLRs because the gain to obtain the 1/3 stops in between is applied in software by the ...
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7answers
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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 it better to shoot with a higher ISO, or use lower ISO and raise the exposure in post-processing?

Suppose there are two photos taken in the following scenario: Scenario 1 - Photo taken using ISO of 3200. Scenario 2 - Photo taken using ISO of 100. Both photos are taken in a medium light scenario....
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8answers
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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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10answers
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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 ...
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6answers
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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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Why would using higher ISO and faster shutter speed yield more noise than using lower ISO and slower shutter speed?

I'm trying to see how this answer correlates with practice. That answer basically says I need to let enough light into the camera and then use the highest ISO value and I'll get the lowest noise then. ...
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2answers
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Is analog gain really actually power-of-two only?

Context I'm using a Nikon D5200, which features extra ISO values between powers of two, that the Nikon D60 did not offer. D60 offers 100, 200, 400, 800, 1600 (1-stop interval). D5200 offers two ...
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8answers
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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 ...
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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) ÷ 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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If I want to shoot darker shots, is it better to increase the lighting and then darken in post to retain clarity?

I'm just getting started - in my last shoot, I was using a 6D with a 50mm/1.4. In low light, the pictures looked fantastic on the viewfinder but on the computer screen, appeared extremely grainy. For ...
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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 ...
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7answers
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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 ...
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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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4answers
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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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3answers
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What is the highest acceptable ISO to use for weddings with Canon 7D? [closed]

I recently had my first wedding shoot(yippie!). For a person like me who usually shoot still life and landscape, weddings is a whole new world. I am used to shooting at low ISO's (800 or less) but the ...
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8answers
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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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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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4answers
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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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5answers
812 views

For night photography with lots of unexposed areas, should I go with high iso and low exposure, or low iso and high exposure?

I have been doing so much research on iso, and for awhile I've been going with the theory that low iso= less noise, so I've been shooting at iso 100 and then adjusting my flashlights and increasing ...
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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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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 ...
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3answers
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Dealing with exposure time during sports photography

I am very new to photography and trying to improve my skills (I don't even know if I have creativity required for photography). I captured some shots of sports. The link to my album (just 6 pics) is ...
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6answers
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Are there general rules for selecting the correct shutter speed and ISO in manual mode?

I have purchased my first DSLR (a Canon 500D) and have been playing around quite a lot within the aperture priority mode, with auto shutter speed and ISO. Anyways as I would like to become a better ...
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7answers
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Can someone give a simple explanation of ISO?

Can someone please explain to me what ISO means in the camera settings? In an answer to a question about taking pictures at a dance party, I was told to use ISO 1600. What does that number really ...
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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, ...
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5answers
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Should I use low-end expanded ISO?

My Pentax K-5 comes with a "regular" low ISO setting of 100, but if you enable "expanded ISO" you can set it as low as 80 (plus go up to an absurd 51200!). I know that in general to reduce noise, ...
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2answers
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How to get bright concert photos?

I've been starting to shoot some live music recently and have been doing an okay job and see an improvement with each time I shoot. However recently I was shooting and all of my photos have come out ...
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3answers
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Can we always talk about noise difference between crop and full frame?

Let's say we have two systems: 1) full-frame camera, 80 mm lens at f/2.2 2) APS-C camera, 50 mm lens at f/1.4 The subject is the same, as well as the camera position, focus distance, shutter speed ...
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1answer
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Film ISO and Push/Pull Processing

I am looking to start shooting film and have been having a look a different 35mm film. What confuses me is film that can be shot at different ISOs/exposure bias. For example Kodak says that Portra 800 ...
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How can I see the photo settings like f-stop, ISO etc. of a image?

I am new to photography and enjoying shooting with my Nikon D3200 camera. Once I take a photo, is there any tool by Nikon or a third party which can give me info like F-stop, ISO, Shutter speed, etc? ...
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7answers
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Why is there an ISO setting when shooting raw?

Raw files are supposed to contain mostly unprocessed data from the sensor. What's the point of having an ISO setting if it doesn't affect the amount of photons counted, but only provides amplification?...
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4answers
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What is the relationship between film speed and the ISO setting on my film camera?

What is the relationship between the speed number of the film you put into your film camera and the ISO adjustable setting on the camera itself? Do you put them on the same number or do you adjust ...
6
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2answers
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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 ...
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4answers
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What is the best order to set exposure parameters (ISO, aperture, shutter)? [duplicate]

Let's say that you're in a very controlled environment, there is no hurry to get the shot, and you're shooting manual. In order to correctly expose the photo, what order should you alter the ISO (if ...
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4answers
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How far to push ISO with Tmax 400 film?

I have a 400 ISO film (Kodak TMax). If I want to push the ISO on my FM2, what is the best setting? Is it ISO 1600, 800 or something else. I notice that pushing to 1600 is very common. Why is that ?
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1answer
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Is there a formula to calculate ISO according to Shutter speed? [duplicate]

Note: This is not a duplicate of "Exposure Triangle things". This is more related to Camera's auto settings i.e. Aperture and human's manual settings i.e. Shutter and ISO and their co-relation. I am ...
6
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1answer
587 views

When is high ISO noise not noticeable?

I noticed that sometimes when taking pictures with my D5100, they come out with very little visible noise with ISO 800 and up, for example this picture. It was taken at ISO 1600 if I remember ...
6
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1answer
440 views

Why is Adaptive Dynamic Range incompatible with ISO Expansion?

[EDIT: The original main question here was "What is Highlight Tone Priority?" It turns out that Highlight Tone Priority, Active D-Lighting, D+, and Adaptive Dynamic Range all mean the same thing, so ...
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4answers
554 views

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: http://1x.com/#!/forum/...
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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 ...
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2answers
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What is DX film encoding?

What is "DX encoding" of roll film, such as 135 format film used in 35mm cameras? How does it work? When was it introduced? Is there anything else I need to know about using DX encoded film in a ...
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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 ...
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4answers
288 views

How to take photo of water splash without photo getting dark? [duplicate]

I just got my beginner DSLR (Nikon D3300) and tried to take a photo of a water splash. I read about aperture, ISO and shutter speed and I know if I set high shutter speed I need to set low aperture ...
31
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4answers
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Is it true that the best images from all digital cameras can be obtained at ISO 200?

Recently a very professional photographer who shoots stunning pictures told me that the best images can be obtained from digital cameras at ISO 200. He also stated that this is what all the ...
38
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6answers
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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?
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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 ...
28
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10answers
4k views

Why use higher ISO when using a tripod and the object is static?

Sometimes when I see a photo such as this one, I wonder why the photographer chose such a high ISO (640), despite using a tripod with a static subject. As far as I know, a lower ISO means less noise, ...