Oh, I forgot. This image was a simple test of a larger filter for the Studio's H5D-50c, that is supposed to have no color cast. The filter used here was a Formatt-Hitech Firecrest Ultra 10-stop ND Filter (100mm x 100mm) and in the few minutes of limited time I had this morning, in the backyard and later, here at the old Mill, I can certainly say that the Filter performs amazingly well. No color cast that I could detect. The moire on the first image is a mystery. But, since it was just a test, I will not bother with it.
Two weeks ago, with the D850, using a Firecrest circular filter, I found that it had a distinct color cast, which I actually prefer...

What to do? I embraced it here, in the Nikon forum:
https://www.getdpi.com/forum/attachment.php?attachmentid=141651&d=1558390678
***Edit***
Then, late last night, I was finally able to drag myself into my little office and process a single image from the mini-shoot yesterday morning. Groggy from a lack of sleep, I found that the overall image shot with the D850, using a very competent 50mm 1.8 G lens and a circular Firecrest filter (from JohnBrew) had more character, better composition and overall, I liked it better!
What now? I have two filters that give me two distinct looks. I like them both! How to use the MF and the full frame to their best advantages is a mystery to me and I must attempt more discovery. Not sure how much I can discover when my "mind-bokeh" is not buttery smooth. I need sleep badly.
I am looking for other opportunities to try out the new filter before we head to the North Georgia Mountains in two weeks to visit my wife's doctor, and spend the rest of the day(s) chasing flowing water!
