Tag Archives: Noise reduction

Noise Reduction using Neat Image

I took the following photo using a Nikon 1 V2, 1″ sensor camera, at ISO 800. This is a big enlargement of a tiny section of a photo of a Titan II rocket launcher (from underneath). This was a very dark location, in the basement of the Evergreen Aviation Museum building.

I processed this image using Neat Image 8, the latest version of the Neat Image noise reduction software. You can see the remarkable improvement from the original, at left, to the noise reduced version, at right.

Voila_Capture 2016-08-29_07-47-05_PM

Today’s noise reduction software enables even small sensor cameras to produce remarkable results in low light.

Noise reduction is built in to Adobe Camera RAW, Photoshop, and Lightroom, RAW Therapee, Affinity Photo, and nearly all image editing software today.

3rd party tools are available in the Google NIK Collection (Dfine2 tool), and the Noise Ninja “community edition” or commercial edition.

Each noise reduction software applies its own methods for noise reduction. You may find that some programs work better on some types of photos than others. I have used Neat Image 7 for a long time and just began using Neat Image 8. For most photos, I just use Lightroom and a combination of “Masking” and Noise Reduction. But for tougher photos or those where I want the best result, I generally turn to Neat Image.

Original Image, after Neat Image processing, and then re-compressed using Mac Preview to 55% to keep the size under 2 MB for upload (in other words, this is a moderate lossy compression version).

DSC_3936_filtered1

Panasonic Lumix GH-2 Firmware 1.1 update just released

Joint update service for Four Thirds lenses | Digital Camera | Digital AV | Consumer Products | Support | Panasonic Global.

Notably, the new firmware adds

  • Improved noise reduction for low light usage
  • Powered zoom lens features to work with the new X-Series lenses
  • 25p mode for PAL cameras
  • 30p mode for NTSC cameras
  • Improvements to auto focus
  • Improvements to burst mode

The better online discussion as to what the new firmware provides is likely to be here.

Noise reduction – I shot a test clip before and after, using 1080/24p video mode at ISO 2500. There is a noticeable improvement but noise is certainly visible – just guessing but it seems it could be as much as 40% to 50% less noise. It is possible that the noise improvement is better at ISO 3200; I believe 2500 is the highest the native image sensor goes to in video mode and 3200 is done through software signal processing. I think. I have not looked at the noise in terms of still images.

HBR – I previously wrote that I wasn’t sure what was happening here. My mistake. On PAL cameras, this is a new 25p mode and on NTSC cameras this is a new 30p mode. My mistake was that I had inadvertently rendered my new 30p video as a 24p mp4 file, which meant some frame blending had occurred. To correct what I wrote previously, the new HBR/1080/30p looks great!

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Reducing image noise in the Canon XH A1

English: Canon Xh-A1 HDV camcorder
English: Canon Xh-A1 HDV camcorder (Photo credit: Wikipedia)

The Canon XH A1 is not very old, but it is tape-based, which today seems quaint and dated!

However, the camera shoots excellent images and its 20x zoom lens remains amazing.  Even at 1440×1080 HDV, it shoots sharper and lower noise images than most of the consumer 1920×1080 camcorders.

But when comparing to my Lumix GH-2 in daylight, the XH-A1 has some image noise that resembles film graininess. Some people actually like that – I do not. I like clean and smooth images and prefer clean over sharp.

Some tips that I have discovered may be helpful to others.

If you shoot using the default camera options, the camera applies no noise reduction strategies “out of the box”. Not surprisingly, there will be some image noise.  While each scene is going to be different, I have found that by configuring the custom presets with some noise reduction options, I get very clean imagery.

I am using the following as a starting point:

  • SHP set to -3
  • Sky Detail to set to smooth/soft
  • NR2 set to “Low”.
  • Coring set to +9

Noise reduction can be improved a bit more by setting NR2 to its medium setting, or reducing the sharpness setting a bit more. These modest changes make a very large and noticeable reduction in noise. The NR1 noise reduction option only works on imagery that is not moving or barely moving, otherwise you get “ghost trails” in the video.

You can also manually set the lowest gain setting to -3db (instead of 0 db). For DSLR shooters, the video gain setting on a video camera is the same idea as setting the ISO level. More gain is the same as higher ISO, which also implies, more noise.

I remain unconvinced that the -3db setting makes any difference in noise. It does buy an addition 2x neutral density equivalent, which can be useful in broad daylight.

For maximum sharpness, I have found (as have others) that the sharpest images occur at an aperture of around f/4.0 plus or minus.

I shoot virtually everything in manual modes, usually shutter priority Tv mode, which means I adjust the neutral density filter settings and the shutter speed to get close to around f/4.0. Much above f/5.6 and sharpness starts to degrade.  You can manually set the aperture to f/9.5 and the camera’s automatic features will go as high as f/22! Images at those aperture settings produce garbage! Incredibly soft, grainy and ugly looking – don’t do that! This is the cause of widely reported and unexplained “grainy” footage captured with the XH A1 – using far too high an f-stop for the lens and sensor. The solution is to use ND filters and shutter speed to keep the f-stop in a low range.

Using these tips you can produce some very clean and very sharp video on the XH A1. I recently did some shooting using both the XH A1 and the Lumix GH-2. If you tweak your XH A1 well, it is very difficult to tell the difference between the XH A1 and the GH-2, unless you have a gigantic HDTV. The XH-A1 shoots at 1440×1080 while the GH-2 can shoot at 1920×1080/24p and /30p, or also 1280×720/60p.

  • 1080/24p is 49,766,600 pixels per second.
  • 720/60p is 55,296,000 pixels per second.

Because of how our eyes process images over time, the higher resolution image might not appear as high to our eyes. Weird, huh?

Finally, if you have noisy images already on tape that you would like to clean up, get Neat Video (http://neatvideo.com). This product is fantastic. On my quad core processor, it can take nearly one hour to clean up a minute or two of HD video, but the results are stunning. (I think they just released a new version that may drop the time to 20 to 30 minutes per minute of HD video on my configuration but I have not installed the update yet.)

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