SNS-HDR and Raw Chromatic Aberration
Posted: Thu Jul 12, 2012 6:05 pm
Sebastian...
Starting with program v1.4.22.1 for Lite/Home/Pro, noise reduction was introduced utilizing DCoffin's "dcraw.exe -n <num>" [set threshold for wavelet denoising]... [ref: http://www.sns-hdr.com/forum/viewtopic.php?f=7&t=352]
...Please consider doing the same for Chromatic Aberration correction in the 'dcraw' Raw conversion as well... ...i.e., "dcraw.exe -C <r b>" ["Enlarge the raw red and blue layers by given factors, typically 0.999 to 1.001, to correct chromatic aberration."]
The following illustration has two duplicate 295x295 pixel 1:1 image area crops of a single Canon EOS-350D CR2 file "dcraw" converted to tiff... ...the only difference in the "dcraw" conversion options is "-C" as shown. The conversion tiffs were then tone-mapped using SNS-HDR Lite with a Default preset...
This may be a challenge to implement because of the generation of 1-3 pixel wide image dimension edge artifacts which may confuse multiple image alignment and de-ghosting algorithms.
More sophicated CA correction methods have been suggested but when CA is corrected before "image merge" and "tone-mapping" of the SNS-HDR auto-workflow... ...the product is much improved...
...especially for those of us that work with nature landscapes and moderate quality zoom lenses.
Thank you for the consideration...
Starting with program v1.4.22.1 for Lite/Home/Pro, noise reduction was introduced utilizing DCoffin's "dcraw.exe -n <num>" [set threshold for wavelet denoising]... [ref: http://www.sns-hdr.com/forum/viewtopic.php?f=7&t=352]
...Please consider doing the same for Chromatic Aberration correction in the 'dcraw' Raw conversion as well... ...i.e., "dcraw.exe -C <r b>" ["Enlarge the raw red and blue layers by given factors, typically 0.999 to 1.001, to correct chromatic aberration."]
The following illustration has two duplicate 295x295 pixel 1:1 image area crops of a single Canon EOS-350D CR2 file "dcraw" converted to tiff... ...the only difference in the "dcraw" conversion options is "-C" as shown. The conversion tiffs were then tone-mapped using SNS-HDR Lite with a Default preset...
This may be a challenge to implement because of the generation of 1-3 pixel wide image dimension edge artifacts which may confuse multiple image alignment and de-ghosting algorithms.
More sophicated CA correction methods have been suggested but when CA is corrected before "image merge" and "tone-mapping" of the SNS-HDR auto-workflow... ...the product is much improved...
...especially for those of us that work with nature landscapes and moderate quality zoom lenses.
Thank you for the consideration...