Larry Jordan is an experienced and respected Final Cut Pro editor and trainer. I subscribe to and keep his newsletters every month. They’re valuable reference materials for some of the editing situations I get into, and good refreshers when I return to editing after having been involved in other activities here in the ITC. His latest newsletter includes many tips and workflow examples, responses to reader questions, and explanations regarding working with other applications – motion graphics, audio, and more. Very highly recommended.
[Note: If you want to keep a copy, download it now; he doesn’t archive them on the site, he incorporates the contents into the articles there.] Here’s an extended excerpt about HDV’s strengths and limitations and his suggestions for getting the best results with this very much in-flux format.
Article: What I’ve learned about HDV
During my recent seminar tour, I had a chance to show many of you how to capture, edit, conform, and output HDV within Final Cut Pro.
However, as frequently happens, teaching goes both ways – I learned a great deal from your questions and comments. Now that the seminar is over, I wanted to share some of my conclusions about working with HDV.
First, HDV can create some very cool pictures—especially when you need to shoot HD video on an extremely low budget. However, HDV also has significant limitations that may, for some, outweigh it’s cost savings.
HDV Strengths
For a relatively small amount of money, you can shoot an HD picture. You also have a variety of frame rates to select from, including 23.98, 25, and 29.97. Some cameras offer additional rates beyond these three. And, the default aspect ratio for HDV is 16:9.
In brief, HDV’s strength is its low-cost, HD images.
HDV Weaknesses
However, on the negative side, the weaknesses of HDV are:
- The HDV image is 1440×1080, which does not precisely match either the 720p or 1080i format.
- HDV is enormously compressed, creating the possibility of significant motion artifacts when the camera is moved, or zoomed, quickly. HDV uses MPEG-2 compression, the same as a DVD.
- This compression groups several pictures into a “group of pictures,” called a GOP, rather than each picture being it’s own entity. 1080i HD groups 15 images into one GOP. 720p groups 6 images into one GOP.
- This GOP method of compression means that HDV is not accurate for timecode or frames when capturing or outputting. (Editing HDV inside FCP is frame-accurate, however.)
- HDV uses extreme color sampling, resulting in very, very poor color keying, color correction, or compositing results. (HDV uses 4:2:0 color sampling, the same as a DVD. Here’s an article that explains it in more detail.)
- HDV renders take about six times longer than DV. This is actually a result of rendering the larger HD image, versus an SD image; still, this will take longer than you expect.
- HDV needs to be conformed, or rebuilt, into a consistent GOP structure before it can be output to tape or exported to a file. This conforming can take an exceedingly long time. (For instance, conforming a 30 second sequence consisting of five shots, took over 10 minutes on my PowerBook. Conforming a complex hour-long sequence could take several hours on a G-5.)
- HDV can only use Print to Tape, not Edit to Tape, due to the timecode inaccuracies of HDV.
For these reasons, I am no longer the fan of HDV that I used to be. What I’ve discovered is that we need to separate how we CAPTURE the image from how we EDIT the image.
