08-11-2015, 03:57 PM
Because the image is so large, when it is displayed in Portrait Professional, it needs to be re-sized and re-sampled to fit the screen. The graininess and artifacts are just a result of that and it only affects the display image.
Also, while in Portrait Professional you can try zooming in on the image and comparing it to the original in a different image viewer to see if there is any difference. The actual image quality and size are not affected, therefore, after you finish processing in Portrait Professional and return to Lightroom you'll see that the image quality is the same as it was before.
Also, while in Portrait Professional you can try zooming in on the image and comparing it to the original in a different image viewer to see if there is any difference. The actual image quality and size are not affected, therefore, after you finish processing in Portrait Professional and return to Lightroom you'll see that the image quality is the same as it was before.