Wierd video problem - 4:3 burn-in on 16:9 HD camera?

Every so often, I’ve been seeing what looks like “burn-in” on widescreen HDTV images at the same location where a 4:3 image would end. The central 4:3 portion is just slightly darker than the far left and right ends of the picture.

First time I saw it, I thought my TV had been burnt from showing too much 4:3 content with black side-bars, but then the program cut to a different camera and the “burn” went away. (whew!)

I’ve also noticed this to a somewhat lesser extent on the local news as they cut between different cameras in the studio.

What would make a camera output something like this? Or could this be some weird artifact in the switcher or whatever processing they do that lops the ends off a widescreen HD image for analog broadcast at 4:3? (This at least, should go away in June, if that’s what’s causing the illusion of a burn.)

However, I’ve also seen this on some DVDs, in particular, a cruise vacation souvenir DVD where they intercut stock footage with actual footage from events on the trip then did the final edit and disc duplication on the ship. The DVD displayed at full 16:9, and I’m assuming that was its native ratio.

This is very much a WAG, but, it seems possible that the camera originally capturing the image was made to capture in 4:3 mode by using a physical mask of some sort behind the lens but in front of the CCD. If so, that could cause unequal wear patterns on the capturing element that would result in different brightness even when the mask wasn’t used.

Or maybe the mask itself was something like an LCD where, even when it’s “off”, it’s still not 100% transparent?

Woah sweet…I’ve been noticing this exact same thing on my parents’ tv, but I thought it was burn-in on their TV. Only I don’t see it consistently, so I am never sure.

Never thought it could be from the broadcast.

Interesting idea, but not one that I’d expect to be used on studio cameras. I did some research on the station in question, and they’re digital HD end-to-end, from the lens to the transmitter. They only downconvert to analog SD at the transmitter, and this get turned off in June. They rebuilt everything in the end of 2006, so the cameras are at best, two and a half years old. I know from personal experience that it only takes one afternoon of being pointed at an open window to put a bad burn on a camera, so there’s no telling what sort of accidental abuse the camera may have suffered. (No, I’m not the one who burned the camera - I was the one who had to un-burn it.)

As such, I don’t think they’d be doing anything with aperture plates in any of their cameras - they seem to use Sony HDC1500 cameras in studio, and those go for a cool $90,000 each, plus lens and pedestal.