Placed raster images above roughly 45-48 megapixels show zero visible difference between Typical and High Quality Display Performance; both render a blocky, low-resolution proxy instead of the full-resolution source. The same content under ~38MP renders correctly with the expected difference.

Steps to reproduce: place an RGB 8-bit image with total pixel count at or above ~45MP (e.g. 6000x8000px) at a large placed size (Effective PPI 700+). Switch between Typical and High Quality Display: no visible change. Reduce the same source to ~36-38MP (e.g. 6000px long side): renders correctly.

Size pattern observed on the same source content: 8000px long side (~48MP), broken, no difference visible. 7500px (~42MP), partial improvement but still jagged. 6000px (~36-38MP), renders correctly. Orientation was tested and ruled out (wide/short vs narrow/tall at equal pixel count both broken), pointing to total pixel count or decoded buffer size rather than a single dimension.

Environment: MacBook Pro M1, 64GB RAM, macOS 15.7.4. Reproduced identically on InDesign 21.4.1, 21.3, and 20.0.

Already ruled out: single-version regression (broken on all three versions tested); corrupted preferences/cache (full reset, Cleaner Tool, reinstall); GPU vs CPU preview (Shift+E, no difference); external monitor (tested with internal display only); zoom level (tested up to 800%); object-level display override; file corruption (image rebuilt from scratch via copy-paste-flatten in Photoshop, same result); file format (PSD, TIFF, JPEG identical); color bit depth (8-bit and 16-bit identical); document-level cache (tested in fresh blank documents). Links panel shows no warnings and correct Effective PPI throughout.

Likely area: since GPU and CPU preview modes behave identically, the limit appears to sit in the routine that decodes and caches full-resolution raster data for preview, not in the Metal/GPU renderer itself.