One of the greatest things about shooting in HD is how beneficial it is for standard definition productions. First of all, after shrinking and cropping, the quality generally looks a lot better than what most DV-based cameras are capable of. The best thing about shooting HD for SD, however, is the amount of freedom you have in re-framing shots and in applying motion.
Since standard definition (DV) is 720 x 480 pixels and HD is 1920x1080 pixels, you literally have the freedom to choose any section of an HD image for use in your SD timeline. I have used this to great advantage in a number of ways. Here are a few examples from the Live In Charleston DVD we just completed.
• A surprise appearance by Andy Leftwich, fiddler for Ricky Skaggs and Kentucky Thunder, was not working as well as we had hoped. The shot where he entered the screen alongside the young girl who was playing at the time was too soon to be an effective "surprise" moment. I was able to use a closer shot of the girl that did not include Andy. No loss of quality from "zooming in" and it looked great.
• My camera operators during the shoot were not able to get super slow crawl zooms that were consistent. Instead of doing the slow zooms live, I just had them give me a wide shot, and I created the zooms in post production. The good news is, with a slow zoom, it is almost impossible to tell whether it was done in-camera or in post.
• One locked down camera provided multiple angles. My shot of the pianist from behind was fairly wide and included the entire piano and artist. From that shot, I was able to extract a nice close shot of the keyboard and an additional medium shot in between. The low angle shot of a group of singers was also able to be used as a two shot (of my choice) where needed.
• There were a number of other ways I made use of the extra resolution, including a few pan shots and a number of fixes to composition. I was also able to choose on a wide shot whether to zoom in to the artist or the screen behind him, which came in handy a couple of times.
There are a few drawbacks to using this technique, primarily the fact that when you choose a closer shot, the background remains the same as the focal length of the lens has not changed. This means that you will not get as narrow a depth of field as you would by zooming in-camera. The focus is also critical. If you did not have sharp focus in your original shot, then your image quality may be better without being cropped. Still, it is a very liberating feeling to shoot and edit with all the options that shooting HD for SD projects provides.
For those not sure how to make use of this technique, here is some quick instruction. Open an SD project in your editor. Import an HD clip. Most editors will resize the clip to a letterboxed size that fills the SD screen horizontally--somewhere around 37%. Using the sizing controls, set the clip anywhere between 51% and 100% that you desire and move the clip up, down, left or right as needed to find the perfect framing. As long as you don't exceed 100%, you will maintain full quality.
Shooting 1920x1080 HD for 1280x720 HD uses the same principles, by the way, but does not give quite as much room for adjustment.