The only time I’ll use zoom is when there’s black bands on all four sides because the station is only available in SD but their broadcasting is letterboxed. I used to have this problem with Doctor Who on BBC America until my cable company added the HD version.
This. I’ve noticed on most TV shows this makes almost no difference. My most notable exception is whenever there’s dancing, e.g. some episodes of the Dick Van Dyke Show.
I almost always use the correct aspect ratio, but sometimes if the top and bottom of a 4:3 program aren’t important, I’ll zoom (but not ever stretch). For example, I only get BBC World News in 4:3, so sometimes if I’m watching that I might zoom because almost all I lose is a ticker at the bottom.
I don’t have a digital TV, but I use an over the air digital converter for my analogue TV. I can’t stand black bars, so I zoom in. Most of the shows I watch are old, anyway, so they were filmed to fit the old CRT screens. I’m the same when it comes to movies. If a DVD is available in full screen, I’ll buy it.
It’s very noticeable to me, and it just makes my skin crawl.
Don’t like black bars? Turn off the lights. The only time they bother me is when the station decides to fill the blank area with junk or make the bars another color besides black. One station here in L.A. (KDOC) briefly put their call letters in big white vertical type on each side of the screen, rendering the channel unwatchable to me. The outrage on their facebook page put a quick end to that.
I usually change the channel for any movie that shows in the full format. I’d much rather see 65% of the screen full size than 100% reduced to a little area in the middle of the screen.