@Ritchie A July 21, 2018
In 2018 VER updated the ABC TV-3 studio backdrop for 'World News Tonight' from tiled plasma to a 5K wide aspect LED display driven by two VER M8 processors. For this installation we added custom white point and color gamut functionality to the M8 processor to match the extremely warm 2700°K studio lighting, as well as solving any other image quality issues that came up in such a non-standard environment.
During the shootout, we demonstrated that an LED display would be visually seamless and would have much better color consistency between the modules, as shown below.
When changing from a display with internal bezels that aren’t raster compensated (e.g., tiled plasma) to a seamless display, existing content most likely will not land in the same physical location due to the removal of the bezels that haven't been compensated for in the raster coordinate system - even if scaling is applied to consider different pixel pitches. If your critical reference point is not at the upper left of the display (e.g., it is just over the left shoulder of the news anchor, somewhere toward the middle of the display), be prepared to re-author or re-position content slightly to make up for this.
This image illustrates the type of issues you can have if you do not fully manage your production component batch sourcing, as well as testing to the display in the end-use configuration during the factory acceptance test (FAT) - these artifacts only showed up when using the display considerably out of it's 'normal' operating range.
In this case, a driver chip was sourced from two different batches/revisions and had slightly different behaviors as a result. The pick-and-place algorithm resulted in a repeated striped pattern appearing in any of the modules produced during the component switch-over. The root cause was discovered by careful analysis of the PCB layout (Gerbers), schematics, and review of the defective boards under a microscope.
To resolve this, the affected modules were hand-reworked with the correct component a few batches at a time, utilizing the on-site spares to backfill and keep the display in operation throughout the process.