This one’s easy – it’s all Epson. All the Epsons are the same in this regard, sporting a motorized 2.1:1 zoom, and huge amounts of lens shift, both vertical and horizontal. All features are motorized.
Both Optomas and the Vivitek have 1.6:1 zooms – still respectable – and a decent amount of vertical lens shift only, so they come in poor seconds to any of these Epsons. All features are manual.
Thanks to motorized focus on the Epsons, it certainly is easier to get the sharpest possible image while focusing, because you can stand by the screen – super close, while adjusting with the remote. With the Optoma and Vivitek projectors, you are back – typically 10 to 20 feet back depending on screen size, trying to see well enough to get the focus dead on.
As a minor side note – I find the Epson optics to be a tad better than the Optoma at maintaining focus from center to edge. I honestly didn’t take that close a look at the Vivitek because it was an early engineering sample, but I had no particular complaint.
Oh, you could go widescreen with the Optoma or Vivitek. But, if you did, every time you switched back and forth from a wide screen movie, to HDTV, sports, etc., you’d have to get up, and adjust the zoom, lens shift, and most likely the focus.
If your projector with manual lens controls is ceiling mounted, or on a high rear shelf, doing those lens adjustments frequently is total impractical, unless you don’t have high ceilings AND you are basketball player tall, so you can easily reach the projector. Even so, you wouldn’t want to!
For the rest of us, it’d be time to break out the ladder. Even less practical! Note: High rear shelf isn’t that likely with the Optoma or Vivitek, because with only a 1.6:1 zoom, most setups won’t let the projector bet that far back.
Even if your Optoma or Vivitek is set up table top, it’s still a pain! I know, because I switch back and forth all the time when reviewing projectors, so it’s always get up, adjust, then later, adjust back to the previous. Argh! You just don’t want to go that route!