So I set up a simple scene, practicing using displacement modifier. I typed some white text on a black background in my photo editor software and saved the image. In Blender, I added a plane, subdivided it quite a bit and did an unwrap Project from (top) view (bounds). I added a material (mix with a diffuse and a glossy shader). Then I added a displace modifier, opened the B&W text image, and adjusted the strength, etc. Everything was good, and I used “Rendered” as the display mode in the 3D view while I adjusted my lighting. One plane with an emission shader, and a sphere with a slightly colored emission shader. In the 3D view, the render preview was perfect. When I rendered the image, however, the colors, specualrity, etc, looked different. There was more color in some areas and different color in others. It was similar to the colors in the 3D view “rendered” option, but definitely quite different. I even tried matching the sampling of both the preview and the render, but got the same results. I have never run into this before.
There are some features that you can have different values for in the viewport and during rendering, change the values for rendering so they are the same as what is set for the viewport (hint, the rendered view always uses values for the viewport).
I’m not quite sure but I would try different Clamp values
Attach a file. Compared to blender render I’ve never seen any major differences with cycles.