re: I don't know anything about them. They are IMAX theatres run by commercial concerns?
As far as I know the only theater in the Los Angeles area that is part of a museum is the one at the California Science Center. There is an Omnimax theater at the Fleet Museum in San Diego. Omnimax shows IMAX movies on a dome instead of a large flat screen. The others are part of commercial theater chains. In addition to showing movies like Magnificent Desolation, and Roving Mars, they show commercial movie blockbusters that have been converted to IMAX. The only theater still showing Magnificent Desolation is the California Science Center IMAX Theater.