Neat Image user guide / Device noise profiles
When you have a set of profiles for your camera or scanner, you can directly use these profiles to process images in Neat Image. Usually there is only one profile that is most suitable to process a given input image. Therefore it is very important to select the right profile, which would provide good match between profile and image. All profiles in a set have been built for different device modes of the imaging device. To make a perfect match between a profile and image, the device mode of a profile should be the same or very close to the device mode used to capture the image.
There are two ways to select a device noise profile that matches the input image:
When you select and open a profile in either way, Neat Image shows the degree of match between the profile and input image. This degree is shown by the Profile match indicator in the bottom of the Filtration Job Editor window. The match degree is calculated on the basis of the image and profile metadata (the EXIF data fields). If the profile’s device mode is exactly the same as device mode used to capture the image then the match is 100%. There is always 100% match between an image and profile built using this very image. If the device modes of profile and image are very close then the match degree is close to 100%. The more different the device modes of profile and image are, the smaller the match degree is. Use the match degree as an indication of match accuracy. If the match degree is low then it is likely that building a new profile (using the current image or the Calibration Target shot in current device mode) would produce better noise reduction results.
Obviously it is preferable to build a new noise profile for each new image, because such a profile would perfectly match the noise of that image. Nevertheless, any noise profile can, with some degree of accuracy, be used to process other images captured by the same device working in the same or similar mode. This is less accurate than building a profile for each image but saves time because building a new profile usually takes more time than re-using a ready-made one. This is especially important if one profile is re-used many times, for example to process a series of images produced in one device mode.
When using pre-built profiles, you may also want to pay attention to the Profile quality indicator in the bottom of the Filtration Job Editor window. A properly-built and fine-tuned profile will show a high value in this indicator. If the profile quality is high (for example, higher than 75%) then you can be sure that the noise profile itself is accurate.
Both Profile quality and match indicators have to show high values for the noise reduction with this profile to be accurate.