Wednesday, October 02, 2013

TV vs. LCD Projector

Part of the deal for getting to try out that 4K tv was that I have to periodically evaluate its effectiveness in helping me convey content to students.  Here's the email I sent to my principal today:

As you know, with the help of Tech Svcs we’ve been able to get the 4k TV in my room talking to my computer over the wireless network via Air Parrot. Currently, though, only my computer monitor (henceforth, “monitor”) displays on the tv; when I switch over to my Elmo document camera, the Elmo image displays on my monitor and on the LCD projector but not on the tv. Tech Svcs will get back to me if they come up with a solution for that. Of course, so much of my instruction takes place with the Elmo that this is a big deal.

Today I showed a Khan Academy video to my pre-calculus students; I had the TV side-by-side with the LCD projector screen. Here’s what we’ve seen so far:

My monitor is “old school”, with a 1.25:1 aspect ratio. The TV, being super-high-def, is 16:9 (1.75:1). Air Parrot and the Apple TV are providing an exact mirroring of my monitor on the tv screen, which means that what is shown on the tv takes up only about half of the TV screen (because the 1.25:1 image is displayed on the tv). I can’t find a way to expand it to take take up the whole screen without cutting off the top and bottom of the image. Because of this mirroring, and because the tv is only 50”, the LCD-projected image is about 4x the size of the image on the TV screen. Perhaps a 16:9 monitor would resolve the first part of this issue? Even if the tv screen were full, the image would only be about half of the size of the LCD projected image.

The tv screen is clearly more colorful and has sharper detail. Text that cannot be read on the projector screen at all can be read easily on the tv screen by those close enough to see it. Again, the image is only ¼ the size of the projected image.

Glare from the lights, door, and windows is another issue. The ideal place to mount the tv in my room, then, would be on the wall between the door and the window, which is absolutely the worst place to mount it from a classroom management standpoint. I could always go into “Bat cave” mode and close the door and curtains and turn off the lights when I’m instructing, but you can imagine the impact that would have on the ability to take notes on my instruction. I don’t have a good solution for this yet.
That's just my first go-round. My principal forwarded this to the head of our district's Tech Services.

1 comment:

Mr. W said...

how much did a 4k tv cost the district? We have probably 4-5 teachers with tvs at our school. They have experienced the same issues. Our projectors get screen sizes up to 70+ inches whereas a tv is 50-55 inches. And for those smaller details it is hard to read in the back of the room. By the way, all of your concerns are the same that our teachers have that have tvs in their rooms.

I went with a Galaxy Note 10.1 tablet and a wireless hub to connect the tablet to my projector. I can give notes from anywhere in the class now since I'm not wired. It connects via wifi direct so even if the school's wifi is down I can still run. The total cost was $90 for hub and cable to convert hdmi to vga. One other thing I can do now is save my notes and upload them to the school website for students that are sick.