Update: This issue has been resolved with the release of Lightroom 6.2
I have been using a Nikon D810 camera for almost a year now and am still frequently impressed with the quality of images and ability to work in low light situations. All of my digital asset management and the majority of my processing is done in Lightroom, which I have been using since the first beta version.
A few months back I upgraded to Lightroom 6 and subsequently installed the latest update (6.1). I still have not bought into the Creative Cloud hype (yet) and prefer using the traditional perpetual license (let’s just say I like owning the things I buy). The workflow I follow is quite simple and when importing RAW images from the Nikon D810, make very little changes to import settings (bar for renaming, adding keywords and organizing into folders). Camera Calibration settings are left to the default Adobe or Camera Standard profile as it gets automatically selected based on the model of camera used. These camera profiles are usually created by Adobe with optimized adjustments for each camera model.
Shortly after the update to Lightroom 6.1, I started noticing my digital images turn from bright and clear to a dull and hazy once the import and preview creation process finished (while the images import into Lightroom they initially look perfect, but once done and all settings applied it turns dull). For a while I could not figure it out and suspected my equipment or camera technique to be the reason and made adjustments in Lightroom to compensate. Not giving up though, I resorted to the internet to find a cure.
Interesting enough, I came across a post on Adobes website describing this specific problem with the Nikon D810 and Lightroom 6.1. As a solution, at least until a new update is released, you need to download a new camera profile and copy to the appropriate Lightroom folder. This replaces the default Adobe Standard camera profile with a corrected version.
This immediately fixed the problem and new images imported reverted back to being bright and clear. You can off course make additional adjustments in this Camera Calibration Panel (as shown in above image) to better reflect your interpretation of the image. The process above does however not fix all the images you have already imported. To do this, you have to edit each image and select Adobe Standard as new camera profile (as it defaulted to Adobe Flat). A quick way to make these adjustments are to sync changes to a range of selected images.
See the following link for more information – https://helpx.adobe.com/lightroom/kb/lightroom-6-1-ignores-the-nikon-d810-adobe-standard-color-profil.html