Q. Can You Help Me Hang My Projector From the Ceiling?

Simon Scotland talks projectors, motorized drops, vertical lens shift and keystone adjustment.


Mar. 03, 2009 — by Simon Scotland

Q. How far down should a front projector hang from a ceiling? It is a 8-foot ceiling in a multi-purpose room. I have a plasma on the wall and want a tab tension screen to drop, but how low will the projector drop from the ceiling? I want a 1080p projector. Which do you recommend in the $4k-$8k range? - Jim, PA

A. When most projectors are suspended upside down from a ceiling, they are designed to work at the same height as the top of the screen. You will be able to adjust the amount of black material that comes out of the projector screen roller so you can get the picture at a comfortable height. If you have a really high ceiling, you can often get the screen manufacturer to provide you with some extra black leader on the screen.

The center projector lens should also be in the center of the screen horizontally. This often means that the projector needs to be installed on a pole hanging from the ceiling. If this is not acceptable aesthetically, there are three ways around the problem. Two are good - one is not!

Motorized Drop
With a motorized drop, the projector will glide into place when in use and hide in the ceiling when not. It’s an expensive option but a great feature in a multipurpose room. Your local CEDIA custom installer can help you with this.

Vertical Lens Shift
Another solution is to buy a projector with a vertical lens shift feature. This allows the projector to be installed above the level of the screen because the image is shifted using optics. This method has little or no affect on the picture quality and will allow you to get the projector closer to the ceiling. 

Different projectors have different amounts of lens shift - although many budget projectors do not have this ability. Some projectors have horizontal lens shift which allows you to install the projector off-center of the screen. Click here for more about lens control.

Keystone Adjustment
Budget projectors have an option called keystone adjustment which allows you to tilt the projector down from the ceiling. Ordinarily this would produce a trapezoid image (the bottom of the image is wider than the top). The keystone adjustment essentially straightens this out. It does so by electronically squeezing the image on the chip inside the projector. This can produce a slightly fuzzy image. This method may be OK in a classroom or boardroom but really should be avoided at all costs in a home theater. Click here for more about keystone adjustment.

As for a projector to use I would recommend the JVC DiLA projectors. The DLA-H350 ($6,000) or DLA-H750 ($8,000) are both really high quality full HD projectors. They feature 3 image chips (which means there is no chance of you seeing the rainbow effect you might get with single chip projectors), produce really deep blacks and have a fantastic contrast ratio. They also have the 34 percent horizontal and 80 percent vertical lens shift. The only downside is that they aren’t super bright, so you will need to make sure the room is relatively dark.



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