As a followup to my previous question; there has been interest expressed in the results of my ND filter tests.
First, I should clarify that the heavy color cast shown in that post was from a single coated B+W filter (6-stop) purchased 5 years ago (77mm, not that it matters). I don't know if it was counterfeit, but it was obtained from Amazon (not a reseller).
Here are the raw images from a new test I did, shooting 4 different angles in the mid-afternoon using 3 test cases at each angle:
1) No filter
2) B+W MRC Nano (82mm) 6-stop (obtained from B&H)
3) Breakthrough X4 (82mm) 6-stop (obtained from Breakthrough direct, thru Amazon)
I spent a few hours analyzing this data. My conclusions:
1) X-Rite Camera Checker is significantly better than Adobe's alternative, in terms of consistency and correctness. Using X-Rite, I was able to make filter and no-filter shots look pretty much identical, and also realistic. The Adobe profiles tended to be far more saturated. Possibly more visually pleasing, but probably not accurate, and also not quite consistent; they didn't always make filter version look the same as no-filter.
2) The B+W and Breakthrough filters both seem pretty good in terms of color cast. They both have maybe a very small cast (nothing as bad as my other single-coated B+W) that is easily corrected but also barely noticeable if uncorrected. I think the B+W leans warm and the Breakthrough leans cold, but I'm not sure. If forced to choose, I think the B+W is slightly better (smaller cast, and I prefer warm). I like the ergonomics of the Breakthrough (the knurling around the outside of the ring), and I like that it's made in San Fran near my home. But I dislike that it's a new unproven company, and I also dislike that it seems slightly more optically dense than the B+W (no idea which one is actually closer to a true 6-stop, but I'd rather err on the side of too fast at this level). I'll probably return the Breakthrough and keep the B+W (and also replace my old 77mm B+W with a new MRC Nano).
I'm curious what others' conclusions are on my points above, i.e.
1) X-Rite vs Adobe
2) B+W vs Breakthrough
EDIT: Per request, here are some renders from my machine. I've only included the 4th angle of all my raw shots, since it contains the most variety of color and objects behind the passport.
The 3 rows, top to bottom are:
The 3 columns, left to right are:
Standard "Adobe Color" profile from ACR
Custom profile from Adobe's DNG Profile Editor
Custom profile from X-Rite's Color Checker
Note that every custom profile was created for that specific photo (i.e. 6 custom profiles are involved in the grid below).
Also note that with with every render, I clicked "auto" in ACR. I suspect this may cause some controversy, but at best it fixes any small exposure differences. And it does seem fairly consistent in how it operates... whatever criteria those are. Also note that this did not radically change the deltas between the results. Even at "default"... the results are the same... but the exposures all look slightly off.
So... since I prefer the X-Rite results, that means I'm focusing mostly on the right column. Within that column, I'm trying to figure out which of the two bottom cells (filtered) most closely matches the top (unfiltered). And I think that is the middle cell (B+W), barely.