i have been examing the resolution charts on dpreview for olympus e1 &e20 and comparing with canon eos-10d and find , that after ni filtration , the resolution the same but a difference due to sharpening artifacts (both color and luminence ) lead to a false conclusion . ni cannot i think reduce sharpening artifacts , and suggest this coul be an area for improvement in ni .
tom
sharpening artifacts
thanks for your reply , on the same topic
in http://www.normankoren.com/Tutorials/Chromatic.html norman koren says
I'm excited because my image editing program, Picture Window Pro 3.1, has a new feature that allows me to easily eliminate color fringing. There was nothing I could do about it in the traditional darkroom.
Color fringing is caused by lateral chromatic aberration, one of the two types of chromatic aberration in lenses, both of which arise from dispersion in glass: the variation in its ability to bend light (its index of refraction) with wavelength (color). Longitudinal chromatic aberration is the change of the lens's point of focus for different wavelengths. Lateral chromatic aberration is the change in a lens's magnification for different wavelengths, resulting in color fringing. It tends to be worst in highly asymmetric lenses, particularly in retrofocus ultrawides (<24mm in the 35mm format), where the rear element may be further from the film than the focal length, and in true telephotos (>200mm in the 35mm format), which may be shorter than the focal length. The two types of chromatic aberration are described in Quality Criteria of Lenses by Schneider Optics. Paul vanWalree has an excellent in-depth discussion. His terminology is a little different: he uses transverse chromatic aberration (TCA) instead of lateral.
Blur All/Chrominance Only
This setting applies only to the Noise Reduction Phase—it determines how blurring is performed. Normally, the red, green and blue channels are all blurred equally. Optionally, the image can be split into two parts: a brightness component and a pair or color components collectively referred to as chrominance.
By blurring just the chrominance, its brightness variation remain untouched while just the color information is blurred. This type of blurring can be helpful for reducing color noise in digital camera images.
see picture window pro ' using the advanced sharpen transformation .
ni could implement this by extending the sliders in the ' sharpening settings ' box y , ca & cb to be blur to the left and sharpen to the right .
tom
in http://www.normankoren.com/Tutorials/Chromatic.html norman koren says
I'm excited because my image editing program, Picture Window Pro 3.1, has a new feature that allows me to easily eliminate color fringing. There was nothing I could do about it in the traditional darkroom.
Color fringing is caused by lateral chromatic aberration, one of the two types of chromatic aberration in lenses, both of which arise from dispersion in glass: the variation in its ability to bend light (its index of refraction) with wavelength (color). Longitudinal chromatic aberration is the change of the lens's point of focus for different wavelengths. Lateral chromatic aberration is the change in a lens's magnification for different wavelengths, resulting in color fringing. It tends to be worst in highly asymmetric lenses, particularly in retrofocus ultrawides (<24mm in the 35mm format), where the rear element may be further from the film than the focal length, and in true telephotos (>200mm in the 35mm format), which may be shorter than the focal length. The two types of chromatic aberration are described in Quality Criteria of Lenses by Schneider Optics. Paul vanWalree has an excellent in-depth discussion. His terminology is a little different: he uses transverse chromatic aberration (TCA) instead of lateral.
Blur All/Chrominance Only
This setting applies only to the Noise Reduction Phase—it determines how blurring is performed. Normally, the red, green and blue channels are all blurred equally. Optionally, the image can be split into two parts: a brightness component and a pair or color components collectively referred to as chrominance.
By blurring just the chrominance, its brightness variation remain untouched while just the color information is blurred. This type of blurring can be helpful for reducing color noise in digital camera images.
see picture window pro ' using the advanced sharpen transformation .
ni could implement this by extending the sliders in the ' sharpening settings ' box y , ca & cb to be blur to the left and sharpen to the right .
tom
