Upload & Sell: On
John, I've never had any problems with B+W UV MRC filter on 100-400. However, this CP is very different....it altered/obliterated the image quality of that good lens.
Now, on my B+W CP it says "F-Pro", but not "MCR". However, I doubt very much that would make any difference because that CP has worked very well on 24-70L, 16-35L MkI and 70-200 f/2.8 non-IS.
Peter, I don't know anything, that's obvious, and I don't know of any documentation thereof, however I surmise...
- That it is impossible that the 100-400L has been produced identically for fifteen years. I surmise there have been improvements and changes on the QT, including optics, coatings and coating methods.
- That CP filters have three important elements, Schot glass, the CP filter mask and coatings in many variations of composition and execution from brand/model to brand/model. That batch-wise or otherwise, filter mask execution and coatings may vary substantially even within brand/models.
- That megapixels of sites on sensors vary in design, pattern, construction, filters, coatings, etc. and then processing in any variation you wish or don't wish.
- That those ray things emitted whimsically by the Sun God enter our atmosphere through water molecules, dust and pollution in infinite variations of colour, diffusion, diffraction and blockage.
Should you extrapolate all the variables, you have pijillions of opportunities for conflicts, compromises and/or confluences. If you add in the dolt and his vagaries on the receiving end, it is a miracle we get what we get.
That all said, I think it all converges in the shadows where the signals are weakest and most difficult to sort out and display. I think adding a filter to the mix is most likely to upset an already tipsy apple cart, perhaps exponentially. I am right now about to replace my 6 or 7 year-old Eizo CG241s with the newest CG276s primarily for better sight and insight into color transitions and shadows and hopefully clear up some vagaries as to what is causing what and what is possible to do about it.