Shooting for Streaming, Part 4

Then I remembered that unlike my resolution chart, which was fixed to a wall, Mr. Bogert’s coat and the curtains were probably moving slightly during the shooting, the coat sharing his body movements and the curtains shifting slightly with air conditioning or motion on the stage.

None of these objects were moving much, of course, but with such fine detail, all it takes is a shift of one line, and the editing or encoding software will have to deinterlace the results. As you can see in Figures 8 and 9, in frame-to-frame comparisons, the progressive source video simply retained more detail. During real-time playback of the streaming file, the interlaced source also showed more distracting motion in the background. In addition, the detail in the scene also highlighted minor deinterlacing artifacts, like jagged edges on chairs or eyeglasses, or the paper scripts used by the actors, that obviously appeared only in the interlaced source video.

What do I take from this? If you shoot lots of footage bound for streaming in the real world, often you can’t control factors like foreground or background detail, or even what your subjects are wearing. In these instances, shooting in progressive mode could yield significant quality benefits over interlaced modes, even at slow shutter speeds and in scenes with limited motion.

To be honest, this finding was new to me, and I couldn’t confirm any similar results in any other tests of progressive vs. interlaced source footage. Though the results make sense, that (of course) doesn’t mean that they are correct. They could have been peculiar to the last two setups that I described, or even the two cameras used in testing.

Overall, if you’re shooting in interlaced mode, and your streaming video doesn’t exhibit lots of noticeable deinterlacing artifacts, or loss of fine detail, keep doing what you’re doing. On the other hand, if your output has been plagued by these issues, moving to progressive source video could definitely resolve them.