Using an i1Pro 2, I created 3 custom profiles(D50, D65, and A) for Epson Exhibition Fiber. I wanted to compare my profiles to the standard Epson profile to evaluate the neutral rendering ability. CTP uses the Lab.icc as the input profile to the profile being evaluated against. I happened to start my testing using the D50 version. The dE starting at the midtones started to go above 3 and managed to stay below 5.5 to the highlights. These numbers were comparable to the Epson profile. I did the same thing for the D65 and A. The D65 rendering had a blue shift(cooler) and the A had a amber shift(warmer). This caught me off guard a bit but after thinking about it it made sense.
Can people opine on these two conclusions?
To evaluate neutral rendering, you must use a D50 illuminant profile.
Since the Epson profile didn't appear to have a color shift due to an illuminant, I concluded the Epson profile was made using D50.
-tony