I have been researching and still haven't found a definitive answer........... Before I start production on a film I would like to know that if I'm planning for theatrical distribution could I crop the film to 1920x817 and it fill the entire movie screen(cinemascope or is it a must to use an anamorphic adapter or anamorphic lenses to achieve this?........ If I use after effects or premiere pro to crop or use a filter to achieve this, is it considered true widescreen anamorphic?............I recently screened a film and it had the bars on the side and now I'm trying to prevent this going forward.

Thanks,
Reggie

I shot an HD feature 9 years ago that was cropped to 2:39 and scanned to 35mm for theatrical release. It "survived" but I wouldn't say that it thrived. There is substantially more resolution involved when shooting anamoprhic lenses on a 1.33 sensor. If you shoot with spherical lenses and crop, it may be widescreen but it won't be considered anamorphic.

Short form answer is: it's possible and it has been done. It's not ideal. However, working with anamorphics is not for the faint of heart. Focus is extremely critical, and it's still not the easiest thing to get matching lens sets. However there are a number of new and modern-design anamorphic lenses coming on the market, which should help foster a renaissance for the format in coming years. What remains to be seen is whether they will demonstrate the well-loved nuances of classic anamorphics (Todd AO, Panavision) in terms of the oval bokeh, blue flares etc.

Thanks Charles....that was very helpful.