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'...
  • 31.2k
21 votes
Accepted

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 ...
  • 13.2k
15 votes
Accepted

Why doesn't noise reduction have any effect in Rawtherapee?

You can only preview noise reduction in RT when you zoom image to 100%, even in latest version. Many other tools have same limitations for previewing, they are marked with small "1:1" label near ...
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 ...
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 ...
  • 3,508
6 votes

Will stacking more images produce more detail in this galaxy photo?

Stacking more images reduces noise to signal ratio, but don't add resolution or details. In order to enhance resolution, my advice is to use a prime lense, instead of a zoom one. Even if it has less ...
  • 1,211
5 votes

Does any software do denoising on Raw files before demosaicing?

Except for dark frame subtraction, which helps get rid of (non-random) pattern noise,no noise reduction is done at the pre-demosaiced level. There are simply too many variables that come between the ...
  • 2,331
5 votes
Accepted

Why does frame stacking alter colours?

Based on the color swapping in the result, I would guess the blue values are being summed into the red result and vice versa. I've made sillier mistakes...
5 votes
Accepted

Does any software do denoising on Raw files before demosaicing?

darktable has a "raw denoise" module that does noise reduction before the demosaic step. In practice, it is rarely better than the other modules that work on the demosaiced image. Most noise ...
  • 1,623
5 votes

What ISO to minimise noise for long exposures with a tripod mounted DLSR?

Generally, the best performance is on your camera's native ISO. This is usually ISO 100, but not always - some Fuji cameras use ISO 200 (go figure..). Check your manual. For decently lit subjects (...
  • 5,900
5 votes

Will stacking more images produce more detail in this galaxy photo?

In my limited experience (back when Astrostack was the hot item, and using video captured at 640x480 with a webcam -- call it 1998 or so), stacking more frames will decrease the appearance of noise by ...
  • 6,319
5 votes

Will stacking more images produce more detail in this galaxy photo?

Yes, but No. Your question is will it produce more detail, and yes stacking more images will reduce noise which will let you see more detail. And at least as important, you are taking calibration ...
  • 81
4 votes

Does any software do denoising on Raw files before demosaicing?

Demosaicing and noise reduction should be done simultaneously. It's best to use the DCRaw program to extract the raw pixel data and then to tackle the problem of reconstructing the image from first ...
  • 3,508
4 votes
Accepted

In RawTherapee noise removal, why does noise apparently come back if I zoom out?

Noise reduction is very computationally expensive process. When you zoomed in it only processes a small part of the image, but when you zoomed out the algorithm would have to process the whole file ...
  • 550
4 votes

How do I stack two photos in Photoshop to reduce noise?

You can also use an median blending (create image stack and apply the "Median" stack mode) File > Scripts > Load Files into Stack Select all layers and use Edit > Auto Align to align them (if ...
  • 32.9k
4 votes

How to best filter away high ISO noise in Gimp?

Adding some info to Akram's answer. You could use try some of the filters from G'mic (a "plugin pack" for the Gimp which has a lot more filters than just noise removal ones). Here's its website and ...
4 votes

Why doesn't noise reduction have any effect in Rawtherapee?

Many previews in image editing applications are just that - previews. To get an exact view of what many effects and settings applied to an image will look like you should export the image with the ...
  • 169k
4 votes

Are there Lightroom plugins for noise reduction which work on RAW data?

It sounds like you want to use an alternate noise reduction algorithm integrated into Lightroom's RAW conversion, as an alternate for or addition to the built-in noise reduction. I don't think there ...
  • 140k
4 votes
Accepted

Can a DSLR take a better photo (less blurry and less noisy) of artworks than a Point and Shoot Camera (Nikon B500)?

There's an old saying about photography: Gear doesn't matter. While true, it is only part of the fuller truth: Gear doesn't matter... until it does. What that means is that better gear won't make ...
  • 169k
4 votes
Accepted

Is Sensor Noise Consistent Between Cameras of the Same Model?

Even the same exact camera will not demonstrate the same "exact" noise characteristics on successive shots. But techniques such as "dark frame subtraction" or other noise reduction processes that ...
  • 169k
4 votes

Very noisy image, looks like stars

Some cameras have a 'long exposure noise reduction' setting which should eliminate hot pixels and reduce digital noise. Two exposures are taken in immediate succession, the first with the shutter open ...
  • 101
4 votes

Issues with dark frame subtraction: Dark frames adding "noise" and changing image color/tint

You misunderstand the purpose of dark-frame-subtraction. While it is a technique used to reduce noise, it only reduces noise that is consistently output from the sensor. Any read noise due to the ...
  • 101k
4 votes

While using Long exposure noise reduction, is it okay if i move the camera after taking the shot, when the camera is doing the noise reduction?

The camera shutter is closed then, during the extra noise processing to examine the dark space. So moving the camera then will not affect the picture, the shutter is closed, and the Viewfinder is ...
  • 12.5k
3 votes

How do I most efficiently reduce noise on images from my Olympus TG-3?

One thing to note is that if you're zooming to "maximum detail" (i.e. 100% crop or 1-to-1 size) on both images, that's not a fair comparison. The Olympus has more pixels, so you're effectively zooming ...
  • 19.9k
3 votes
Accepted

Improving My Night Photography Shot with Post-Processing

Try about ISO 200 @ f/8 for 30 seconds and work from there. That's three stops slower ISO and 4 stops (and change) slower aperture, so that is seven stops slower than what you used. Since some of your ...
  • 169k
3 votes

How do I remove noise in the sky portion of my photo?

Some of the below repeats parts of other answers. Apologies for that... The higher the ISO, and the longer the shutterspeed, the more noise you're going to get. Some cameras are better than others....
  • 266
3 votes

Image Stacking for noise reduction using MATLAB

Image stacking is a process by which you can reduce noise, but it doesn't work by adding the images together additively, but rather averaging them. The reason that stacking works is that signal from ...
  • 34.4k
3 votes

What is optimum setting for capture in night from moving objects, when diaphragm is fixed?

You cannot beat physics. You have three variables to play with to adjust exposure: Aperture, time, and ISO (which, i'll assume, you mean with "gain"). Since your aperture is fixed, you can only ...
  • 6,800
3 votes

What is optimum setting for capture in night from moving objects, when diaphragm is fixed?

Actually, there are four things you can modify - in addition to shutter speed, ISO and aperture, as mentioned in the other answers, you can also modify the lighting (assuming your subjects are ...
  • 2,903

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