Below are some of the most frequently asked and answered questions about Neat Image. Please feel free to ask questions regarding Neat Image by e-mail or in the Neat Image community forum.

General questions

• What is the difference between Demo, Home and Pro editions?
• Should I uninstall Demo prior to installing Home / Pro edition?
• Should I uninstall the older version of Neat Image prior to installing a newer one?
• I think I have found a bug. How can I submit a bug report?

Filtration-related questions

• Why do I receive some crystal-like artifacts in the filtered image?
• Filtered image looks 'plastic'. Why?
• What is frequency?
• The filtration process is not very fast, is this normal?
• How to filter only the color noise (not the brightness noise)?
• What is YCrCb?
• Is processing via Neat Image best done before or after any other processing (i.e. tonal/color correction)?
  
  

The Demo edition of Neat Image has some of the functionality disabled. In particular, it does not save images in TIFF format and does not copy output image to the clipboard (the Demo edition only saves images in JPEG with fixed quality). Non-Demo editions do not have those limitations. Please see Feature map for more details.

That is not necessary. The Home / Pro edition can be installed over the Demo edition.

Usually that is not necessary. A newer version can be installed over the older one; it will replace the old version.

Please use the online bug report form; please fill it out to let us know all the details necessary to reproduce the problem.

See more information about known bugs and bug fixes.

Presence of many residual noise elements is usually a consequence of using a poorly built noise profile or a profile built for another device and/or device mode.

The crystal-like artifacts (usually these are the residual JPEG compression artifacts) look like thin lines in the filtered image. They can be easily eliminated by increasing the high frequency noise level in the filter settings (available in Advanced mode).

The reason is that too much filtration was applied. Let Neat Image keep some noise to produce natural-looking results. Adjust the noise reduction amounts; for example, reduce the noise reduction amount in the luminance (Y) channel to 50-70%.

Also, make sure the device noise profile does match the input image. Using an incorrectly chosen or poorly built profile can both produce plastic-looking results and leave residual artifacts (see the previous question).

The term (spatial) frequency is used in Neat Image to denote image elements (both important details and noise) of certain size.

High frequency corresponds to image elements of smallest size. Medium frequency corresponds to elements of medium size. Low frequency corresponds to image elements of (relatively) large size.

For reference, see the noise samples of different frequencies
in the Noise Filter Settings tab of the Filtration Task Editor.

This is normal, because the filtration algorithm is quite complex. We are working on further optimization to provide better performance.

Set the value of the luminance (Y) channel noise reduction amount (in the Filter Settings box) to 0%. That will disable filtration in the luminance channel and Neat Image will only filter the color noise.

YCrCb is the name of a family of color spaces widely used in digital imaging, television, image compression (e.g., the JPEG compression stores color images in this space), etc.

In 'YCrCb', 'Y' corresponds to the luminance channel, 'Cr' - to the Cr chrominance channel covering the red to blue-green range, 'Cb' - to the Cb chrominance channel covering the blue to yellow range. Because this space enables easy separation of the luminance and chrominance information, it is very suitable to conduct noise reduction.

Such operations as tonal/color correction are quite conservative from the standpoint of noise, i.e., they do not significantly change the noise characteristics of the image. Therefore, filtering before or after is about the same as long as the noise profile is built and applied at the same stage of image processing. For example, do not use a device noise profile built with an unprocessed (with the color correction not yet applied) image to filter a processed image.

Some digital cameras apply some color correction internally. Other cameras allow access to unprocessed RAW data. Neat Image is a generic filter, which can be applied in both cases. The only requirement is to build and use a noise profile in the same point of the post-processing workflow.

On the other hand, image sharpening applied to a noisy image makes it much noisier. It is best to apply Neat Image filtration before sharpening. However, the sharpening and noise filters of Neat Image itself can be used together because Neat Image's sharpening is applied AFTER its noise filtration.

If you are not sure, try to use Neat Image as close to the source of the input image as possible.