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33

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-photographer perception of noise in digital images. I also did not see any in the first several pages of results of a Google Scholar search. only photographers ...


18

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 customers say words like, 'dots', 'roughness', 'pixellation' etc. Those who noticed it disliked it and told me that they hoped that I will ensure that the the ...


14

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 - but what exactly that background/perception mix is...well, who knows? My wife is in school for her PsyD and has access to more reports than I could ever hope ...


11

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 photograph lacks detail (e.g. poor focus or limited depth of field, or camera shake, or lens distortion, or noise, or over-saturation, or limited pixel count). However, ...


9

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) to get "popcorn" sized grain with practically no enlargement. The noisy grain-pattern was what we were after as aesthetic expression. We'd try the same thing ...


7

They don't. You're interpreting the raw data wrong. According to the PiCamera documentation, the Pi's 10-bit raw data is encoded as 5 bytes in the following manner: The Pi's Bayer array is BGGR. So the first four bytes contain the most significant bits (bits 10–3) of the blue, green1, green2, and red sensels, respectively. The fifth byte of data packs the ...


5

This is a known issue with the Nikon 18-200 ƒ/3.5–5.6 VR lens. Some people have reported a simple workaround, some others report the workaround doesn't work. The Problem Apparently the VR mechanism inside the lens emits some infrared radiation, enough that it can be picked up in some cases, especially in long-exposure photography. Although, 30 seconds at ...


5

What kind of lighting are you using? I think that is where a lot of potential for improvement lies. With textured subjects, the angle(s) of your light source(s) with regard to the camera's optical axis can make a significant difference in contrast and the amount of detail you can see. Using flash will also allow you to "kill the ambient" and freeze any ...


5

There will be minimal difference; particularly for macro type photography where the aperture generally has to be stopped down in order to achieve a usable depth of field. The D610 has a pixel size of 5.95um and the D810 has a pixel size of 4.87um. In order to resolve all visible light wavelengths to that size requires a (theoretical) perfect lens used at f/...


4

I think what matters is not who is looking at the picture, but what the picture is about. If we are talking about photojournalism, or about a photo of a special instant - something hard to shoot - then noise is not going to be important. That doesn't mean that it is not going to be noticed, everyone can see the grains. It's just that the subject is so strong ...


3

Some links for you : Software : Try Deep Sky Stacker. It's freeware and designed for astrography. The site has some useful tips on technique and method as well, so read those even if you don't use the software. General purpose software : I do use Darktable for general photography processing, but it's not designed for astrography. For very tough RAW ...


3

Why my RAW is noisier than Jpeg? Because the JPEG created by your camera included the noise reduction contained in the camera's raw processing engine. When you work with the raw file in another application, none of the in-camera processing used to create the JPEG is used by your external raw processing application. It uses its own noise reduction algorithms ...


3

Blue skies are typically noisy with any camera, and at any ISO. It is due to the RGB filtration of the individual photosites/pixels. With the common Bayer filter array 50% of the photosites are filtered to a green centric wavelength, and 25% are filtered to blue and red centric wavelengths (each). So when you photograph a blue sky only 25% of the ...


3

There is no way I can imagine that the same jpg can one day be 'clean' & another day be 'grainy', then the next back to 'clean', unless it is being viewed by an app that is failing to correctly load it, or is re-interpreting at load. The file itself is either good or it is broken. Broken files don't demonstrate 'grain' they either show large blocks of ...


3

Your premise is wrong and lies already in the definition of noise. if it would affect all sensor sites equally, it wouldn't be noise but only an offset. Noise means that some more-or-less random value is added to the signal, different for each sensor site. That's what makes it so hard to remove. see What is noise in a digital photograph? for an explanation ...


2

I was wondering: how is it possible for a smaller sensor to perform better in low-light, if it is capturing much less light than the bigger sensor? Short answer: We don't know that it is capturing much less light than the bigger sensor. Longer answer: Smaller sensors capture less light than larger sensor when certain assumptions are made: Both cameras ...


2

I believe ISO 2000 is a bit high. I'd experiment with lower ISO, like 800. This is a good article explaining ISO in astrophoto. Also, 2.5 secs per picture is a bit low for an object like that. That's why you only get the bright core, but no arms. Can you expose more time, like 15 secs or more? Taking more frames will help you to increase signal-to-noise ...


2

Given that sensor noise affects all sensor sites equally/randomly, why does the raw unprocessed Bayer data have such prominent vertical stripes? As @scottbb already explained the RAW format layout and why this creates the striped (in the chat session), you should know now that these are just low level "noisy bits" from four sensor sites (BGGR) combined into ...


1

Hot pixels are normal for long exposures. Additionally, the sensor and electronics get warm and this increases the noise level. The noise level is random, but the hot pixels are not and can be fixed in-camera Your camera has a feature called Long Exposure Noise Reduction. If you turn it on, the camera will take two exposures. The first will be a normal ...


1

The sound is normal. The flash is rapidly firing at super low power so you can see what the effect of the full flash will be. I never use the feature myself.


1

Since you're in digital, there are a lot of things you can do that aren't possible in film without a ton of work. One of the biggest is being able to easily edit photos together. It's only a little more work taking the pics. If the there's too little light or too much or both together, take composite shots. On this shot, I'd take the image of everything ...


1

"I was wondering: how is it possible for a smaller sensor to perform better in low-light, if it is capturing much less light than the bigger sensor?" It really isn't possible; unless there is a significant difference in the technology in use (i..e CCD/CMOS/BIS sensors). In this case both sensors are of the same design, but possibly different generations... ...


1

In the general case, if you find that the images as taken by the camera are too light or too dark, you can use exposure compensation. If you shoot subjects that are very different from their background (crows are rather typical) you can use center-weighted or spot metering to make the camera set the exposure for the subject and not the whole image.


1

Regardless of what mode you use, it's helpful to know how aperture, shutter speed, and ISO relate to each other to keep exposure constant. Open the aperture (smaller F-number) ⇒ more light reaches the sensor ⇒ increased exposure. Increase shutter speed ⇒ shorter exposure time ⇒ less light ⇒ decreased exposure. Increase ISO ⇒ increased sensitivity ⇒ ...


1

If you reduce the brightness of the raw image you processed yourself to match the jpeg image processed by the camera, the noise will probably be very similar. Another way of looking at it is that if you increase the brightness of the camera produced jpeg image to match the brightness of the raw file you processed, it will show just as much noise as the raw ...


1

On your RAW image after noise reduction applied, there is still too much color (or chromatic) noise. You have basically 2 main kind of noise: luminance noise and color noise (also named chromatic noise). (more details about the 2 kind of noise here). I am not familiar with ACDSee but according to their website, you can indeed fine tune both noise reductions (...


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