Recently I shot my second online cinematography course, provisionally titled The Secrets of Cinematography, which will be out in the spring. In it I shoot on a Z Cam E2-F6, a full-frame camera. As far as I can remember, the only other time I’ve shot full-frame was for the miniature map in Above the Clouds, captured on a Canon 5D Mk III. So I thought this would be a good time to post a few facts about large-format, and a good excuse to get some more use out of this graphic I created for the course…
First of all, some definitions:
- Super-35, about 24x14mm, has been the standard sensor size since digital cinematography took off in the noughties. It’s based on an analogue film standard which has its own complex history that I won’t go into here.
- A large-format digital cinema camera is any that has a sensor larger than Super-35. It’s not to be confused with large-format still photography, which uses much bigger sensors/film than any currently existing for moving images.
- Full-frame is a subset of large-format. Confusingly, this term does come from still photography, where it is used to identify digital sensors that are the same size as a frame of 35mm stills film: 36x24mm.
These are the differences you will notice shooting in large-format versus Super-35:
- Lenses will have a wider field of view. (You’ll need to make sure your chosen lenses have a large enough image circle to cover your sensor.)
- If you increase your focal length to get the same field of view you would have had on Super-35, perspective will be rendered exactly the same as it was on Super-35…
- … but the depth of field will be shallower…
- … and you may see more imperfections at the edges of frame where the lens is working harder. (A Super-35 sensor would crop these imperfections out.)
- Picture noise will probably be finer and less noticeable due to the photosites being larger and more sensitive.
In the case of full-frame, the crop factor is 1.4. This means you should multiply your Super-35 focal length by 1.4 to find the lens that will give you the same field of view on a full-frame camera. (Some examples are given in the graphic above.) It also means that you can multiply your Super-35 T-stop by 1.4 to find the full-frame T-stop to match the depth of field.