I've just watched some of the webinars on X-Rite's site from Joshua Holko about shooting and processing snow/ice images. Very informative. He discuss's using the passport color checker to create a camera profile for Lightroom. He mentions that you only need a single light source for the profile BUT that you need separate profiles for each ISO! This would be a lot of work to generate and also prevent applying during the import stage, unless all images were shot at the same ISO.
I havn't seen this recommendation before - is it accurate? Whats the consensus here about needing a different profile for varying ISO?
Mark
may be create profiles for various sensor saturations (in raw channels) = different exposures, to account for possible non-linearities /usual suspects = deep shadows or where you are very close to clipping in raw/ of some kind... albeit some implementations do better with readout noise /deep shadows benefit/ when gain /popularly known as ISO/ is higher (Canons are a prominent example), up to a certain limit of course - so that might also be a factor along with exposure.
however consumer grade shooting of consumer grade 24 patch target with profiling software incapable to use an actual target measurement probably will make that really really useless...
PS: Eric Chan however suggested to bracket shots and use the most exposed raw (converted to DNG) that Adode PE will accept - may be OEM software from XRite shall follow the same guidance.
PS: also ACR/LR can apply some default settings based on ISO recorded in raw = so you can automatically apply different
snake oils profiles for different ISOs
