Click to enlarge. SO close
Optoma HD81 Remote Control
It's pretty (I love those blue LED lights, even though I'm not sure they are as easy to read as other colors), it's loaded with buttons, and the layout is pretty good, which means controls are logically grouped, and there are lots of different sized buttons and it's not all rows and columns. As a result it is easy to navigate and find what you are looking for, without needing the backlight. The Backlight, incidentally, comes on whenever you press any key.
Unlike many projectors the HD81 has one button for powering up, the other for off. Below them, your primary preset modes, which consist of Users 1,2,3 and the ISF Day and Night settings. The last button in the group, is the Iris control. (I'm not sure why its up there, but, it's easy to find.
Directly below those controls are four image controls in a slight curve - Edge enhancement, Gamma, Color Vividness, and BW (black and white image) enhancement.
Right below that, the obligatory four navigation arrow keys and a center Enter button.
To the lower left, the Menu button (just about where you would expect to find it, and opposite it, the Demo button (again, this allows you to compare original settings with the changes you make.
The next two are vertical bars for the Vertical image shift, and Overscan adjustment (for those pesky TV images that have noise at the top or bottom of the image. I'm not sure why they get such prime real estate on the remote, but, so be it.
Finally at the bottom come about a zillion input selection choices. The three HDMI's are in the first row, with space between them and the other twelve buttons. That's abount it, except to say that it fits well in the hand, and you can access most of the buttons you are likely to use, without needing your other hand, or having to shift your hand up and down on the remote. Overall, a really nice remote control. And, don't forget those lovely blue lights!
Optoma HD81 Lens Throw and Lens Shift
As noted, the HD81 lacks adjustable lens shift, which pretty much eliminates mounting the projector on a back wall. The projector will end up being placed (do to the significant fixed lens shift), either well below the bottom of the screen, or ceiling mounted well above the top of the screen. If you are using a 100" diagonal 16:9 screen that offset is going to be just over 16 inches (above the top, or below the bottom of the screen surface.
As to distance, again for a 100" diagonal screen, the front of the lens can be as close as 13 feet 6 inches, to approximately 16 feet 2 inches from the screen.