Okay with the ML instruction page and a free trial of PS, this is very easy to accomplish
Just generated aspect ratios for the 720x480 demensions via this website
https://www.shift-e.net/tools/#!/matte-generator and then matched the thickness of the black letterboxing accordingly to each of the desired ratios.
Below are:
2.00 Stararovision/Univision
2.20 uncropped Super Panavision 70 large format
2.55 original 1950's Technicolor Anamorphic Cinemascope
2.76 uncropped Ultra Panavision 70 large format
Unfortunately I am unable to figure out how to create transparent gridlines for the rule of thirds to overlay onto these crop marks at the moment-- anybody know of how to do it please say so or link some directions from a video tutorial or how-to webpage
Your welcome. Enjoy!
