The Optoma UHD51a has a unique set of features that set it apart from the UHD50 and UHD51. As a result, his thread is for UHD51a owners only. Thread topics should be restricted to the actual use of the UHD51a by those who have already purchased the projector. For questions about the UHD51a, discussions of UHD50 or UHD51 or comparisons to other projectors, please see https://www.avsforum.com/forum/68-digital-projectors-under-3-000-usd-msrp/2955818-optoma-uhd51a-4k-hdr-3d-dlp-projector-w-alexa.html