In 4.18, Buffer Visualization Modes appear very similar to their representation in Buffer Overview. In 4.19 and Main (CL 4008322) the results are very blown out. Similar issue reported in UE-29947.
Per Licensee:
I believe that there may have been gamma issues with various Buffer Visualizations going back to at least Jan 8th 2015. However with the 4.19 release we are now seeing inaccuracy in the Base Color and World Space Normals buffer visualizations caused by the specular channel affecting the visualization. In some scenes this results in the visualization being so blown out that it becomes useless.
Result: Buffer Visualization results are inconsistent with Overview mode. Results tend to look very blown out.
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-57992 in the post.