Lens Throw and Lens Shift
The HT5550 has separate vertical and horizontal lens shift. As with other projectors, the more you use of one, the less shift is available for the other. Most of us, fortunately, would tend to need vertical, but little or no horizontal shift.
While the HT5550 can’t match the much more significant amount of shift found on many 3LCD and LCoS home projectors, it still offers a whole lot more than most DLP’s which offer only minimal amounts (such as their lower cost BenQ HT3050).
As usual, these are the distances for filling a 100” 16:9 screen (measured from the front of the lens to the screen):
Closest: 118.1 inches 9 feet 10.1 inches
Furthest: 190.0 inches 15 feet 10.0 inches
Lens Shift: The manual has conflicting numbers but the good ones seem to be:
Vertical: range up to 0.65 of vertical height. (For a 100” screen that height would be just a fraction shy of 50”. That works out to that the image can be moved a total of .65*50, or approximate 32.5 inches total – which would be up or down 16.25 inches. (the other spec says only 5 inches of range, which is obviously wrong, as I can tell simply by playing with the controls on the BenQ.
The horizontal shift is a maximum of 0.28 x image width, which would be about .28 x 87 inches.
The plentiful vertical lens shift makes rear shelf mounting mid height or above practical if the room isn’t too deep. As mentioned earlier BenQ vents out the front (pushing air to the front sides – away from the lens), which is also critical for rear shelf mounting so the projector
The HT5550’s all glass lens looks really good. We’re talking on 4K content, from 4K Blu-ray movies. As usual, one can do so much these days with various image “sharpening” controls, that being a native 4K projector (of top quality) doesn’t mean that the projector will seem sharper than other projectors that are “merely” 4K UHD or 1080p pixel shifters.
I did detect just a slight amount of lens defocusing as the projector warms up, going into full power mode (after about 25 minutes). I did not check the lower power settings. The amount of defocusing is less than a couple of other of my favorite projectors, and some defocusing can be spotted on many projectors. I recommend focusing when the projector is fully warmed up, in this case, if you are mounting it. If you are moving it around, well, you will be refocusing every time you move it. Many of you simply won’t notice the defocusing unless you are looking for it. (Here’s a reminder, some hard core enthusiasts intentionally slightly defocus, to soften the image, because most manufacturers – all considered, are over sharpening with the many detail enhancement, edge sharpening and other tools available.
The lens is manual in all ways. The zoom and focus controls are on the lens barrel, while the two lens shift controls are on the top of the projector behind the lens. With manual control, going widescreen for Cinemascope type movies is mostly impractical, at least if ceiling mounting.
If using on a table top, as I do when reviewing, on the other hand, it just means you get up, and adjust the zoom larger for the wider, less tall Cinemascope image, adjust the lens vertical shift, and then refocus. That will get you out of your chair for a good minute or so, each time you want to change from widescreen to HDTV shape or the other way. This is typical for projectors under $3000, with only a handful of projectors – mostly Epson’s with the needed power lens features.
BTW if you overall like the HT5550, but want to go widescreen, and are using the projector table top, my take is “go for it”. If ceiling mounted – on the other hand – only if the ceiling is 8 feet or less, and you are inches taller 6 feet, should you even think about it. My projector is mounted from an 8 foot ceiling, but at 5’ 8” I just really can’t work the lens controls without a step stool. Good luck!