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33 votes

Is it true that "only photographers care about noise"?

I do expect work has been done on noise perception to build perceptual models to compress images and compare image quality. However, I am unaware of any studies that compare photographer vs non-...
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32 votes

Why would using higher ISO and faster shutter speed yield more noise than using lower ISO and slower shutter speed?

So I first shoot with ISO 1600 and shutter speed set to 1/125 second and then I shoot with ISO 3200 and shutter speed set to 1/250 second. The amount of light should be identical and indeed both shots ...
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32 votes

Multiple copies of the same exposure, but randomizing the noise?

To achieve what you're thinking of you would have to know what the noise was. If you knew what the noise was then you could just remove that to get clean images.
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28 votes
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Signal to Noise Ratio over the years

This data was iffy then — not really enough data points, and the trendline is dubious: Source: a very timely xkcd That said, the company DxOMark does measurements of camera sensors all the time, ...
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26 votes
Accepted

How can I reduce noise at ISO 100 in photos taken in the twilight?

This is a perfect example of "expose to the right" — that is, even though you want the final result to be low key (largely dark), take the initial exposure as bright as you can (without blowing out ...
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26 votes
Accepted

Why is the North America Nebula so hard to see on this astrophoto?

Your exposures are very different. Ignore the quantity of images that you captured for a moment... and just compare the the single exposure settings (for reasons I'll describe in a moment). Top: 13 ...
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  • 3,567
22 votes

Why do my photos appear grainy when taken at the widest aperture?

Looking at your samples, the answer seems clear to me: that's not grainy, that is, actually, out of focus. Here's a 1:1 crop of your wide-open image: It seems pretty apparent that the wooden sign is ...
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  • 140k
22 votes

Can I use a single RAW file with stacking to reduce noise?

Can I get the same result by coping a raw ( same exposure ) file many times and stacking to reduce noise as I would if I used many separate exposures? No. If you stack copies of the same image, you'...
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21 votes
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Why is there the illusion of detail in photographic noise?

While there may be truth to the principle that noise adds the illusion of detail, in this example I think you are misinterpreting what you are looking at. If I remove all the noise in its lower ...
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  • 13.2k
21 votes

What texture is used in this photo?

That's a 'halftone pattern'. Halftones are a method of creating color separations for offset printing printing presses. This image was probably scanned from an offset printed piece. Offset printing ...
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19 votes

Multiple copies of the same exposure, but randomizing the noise?

Image stacking works to reduce noise because the noise is random — or at least, ideally so — while the stars are (famously) constant. That means that (once you've corrected for rotation) the stars ...
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18 votes

Is it true that "only photographers care about noise"?

Based on my informal study of my customer preferences and anecdotal evidences, I found that some laypersons do notice noise. 'Noise' is not a familiar term to most non-photographers but I heard my ...
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15 votes

Do mirrorless cameras have more sensor noise because they are constantly exposed to light?

DSLR camera sensors are only exposed to light when the picture is taken, so the sensor presumably produces less noise than if it was always exposed to the light. I find support for this in the way ...
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14 votes

Is it true that "only photographers care about noise"?

I don't think you'll find that this topic has been studied to the degree that you're looking. You may have some luck in finding a study on perception based on some tangible knowledge or background - ...
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  • 20.3k
14 votes

Why does my ISO 1600 picture have a grainy background?

It's called "photon shot noise." For a given intensity of light there is also a given amount of noise; and the noise component is equal to √(photons/time/area). So, with more light intensity/...
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14 votes

Why does my ISO 1600 picture have a grainy background?

why is it grainy in the background You chose to limit the amount of light collected by the sensor to the point Poisson distribution noise has a noticeable effect. Instead of shooting at ISO 1600, f/6....
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13 votes

Do different lenses affect noise level?

In short, no. See What is noise in a digital photograph? for a fairly comprehensive overview of what does. The main aspect of a lens which might cause increased noise is if you are shooting at a ...
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13 votes
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Why do RAW images in Darktable have a lot of noise?

Michael is right. More precisely: The RAW image contains two images: the embedded JPEG preview, which has your camera's processing applied including noise reduction, and the RAW data. When you open ...
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13 votes

Can I use a single RAW file with stacking to reduce noise?

You cannot. Removing noise via photo stacking works on the principle that the noise in your images is random, and appears in different places of the image between exposures. When you stack multiple ...
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13 votes
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How to avoid the grainy background in sunset picture?

As to the trees being unsharp: It is very difficult to tell, but I think that the autofocus decided to get the house, not the trees in focus. It really is best to specify a certain AF point (p. 61 in ...
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  • 6,307
12 votes

Why are my low light photos noisy /blurry, but Alien is perfect?

Why are my low light photos noisy/blurry, but Alien is perfect? There's a world of difference between creating a dark image and creating an image in the dark! The scenes in a Ridley Scott sci-fi ...
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  • 31.2k
11 votes

Is it true that "only photographers care about noise"?

Many non-photographers will appreciate a sharp, lifelike image, with a high degree of detail visible. Non-photographers may not always be able to distinguish all the different reasons why a ...
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9 votes

Why are my sports team pictures fuzzy?

I do not think your photos are fuzzy,I think they are noisy. You will get the best quality image by shooting as close to the 'native' ISO as possible. For most modern dSLRS that is typically ISO 100 ...
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  • 14.3k
9 votes
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Strange pattern in picture

These are demosaicing artefacts introduced when converting the image from the bayer array that the sensor records into an image with complete colour information for each pixel. In an effort to ...
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  • 621
9 votes

Multiple copies of the same exposure, but randomizing the noise?

What you're asking about is generally called star-eating. From an algorithm point of view, in an astrophotograph, how can software determine what is signal (that is, stars) vs. what is noise? A ...
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  • 31k
9 votes

Is it true that "only photographers care about noise"?

Beauty is in the eyes of the beholder. It used to be popular to shoot Kodak Royal Pan X film rated at 'ASA' 1200 (That was fast back in the day.) and "soup" it in Dektol (Kodak D-72 paper developer) ...
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  • 5,405
8 votes

Is analog gain really actually power-of-two only?

It all depends on the specific camera model and the design of the sensor and the firmware installed. Many Nikon cameras with sensors made by Sony amplify the base signals by 1/3 stop intervals. Other ...
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  • 168k
8 votes

Why is there the illusion of detail in photographic noise?

Noise is random, it causes gray values to fluctuate from one pixel to the next. This is then random information present at the smallest scale in the picture. If you remove it, then it gives the ...
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