When a film is listed on IMDB, and the Cinematic Process is given as Spherical, does that mean that they were all filmed in the Academy Ratio?. This is interesting, as it seems a number of films were shot that way, then masked for Widescreen.

Yes. 'Spherical' means non-anamorphic, so usually refers to any widescreen processes that did not use a squeeze lens.

If titles are marked 'spherical' and masked, it will probably have been shot at standard 1.85:1 on 1.37:1 stock, and then formatted with black bars for theatrical release.

Worth noting: Paramount's VistaVision was a non-anamorphic side-winding large screen experience at 1.85:1, while Todd-AO and MGM 65 were 70mm formats which ran vertically through camera and PJ, and had a 2.2:1 aspect ratio. All three were spherical processes. Panavision bucked the trend by developing a 1.25x anamorphic lens for MGM 65 which resulted in a 2.76:1 ratio for Ben-Hur.

Thanks Martin.