One question we are often asked is, "What projector should I use?" This is the kind of question that doesn't have a hard and fast "Get an ACME 9000" kind of answer. It comes down to several factors including what kind of Haunt you are planning and your budget.
The closest thing we have to a blanket answer on this topic is this: Find a projector with the highest Lumens and resolution that fits within your budget. Even this, though, brings up more questions, so we will try to cover as many as we can here.
Lumens are a measurement of the strength of light emitted by a source, in this case, a projector. A common aim for projectors is around 2000 lumens. (A projector is rated by the maximum strength of light when the bulb is new and at its brightest.) However, you should evaluate the space where you are planning on projecting an effect to see what works best for you. You may not need something that bright to make your visual point, especially considering many spooky motifs can actually be enhanced by a lower light level.
Resolution is a measurement of the number of pixels in a frame of video. There are many resolutions out there. The highest resolution you will probably run across is Full HD, 1920x1080. These numbers refer to the number of pixels in the width and height, so a Full HD image will have 1920 pixels across, and 1080 up and down. The higher the resolution your projector can handle, the larger the image you can project before pixelization is noticeable. We also recommend choosing a video file that matches your native resolution on your projector. This ensures maximum compatibility between video and projector. Keep in mind, though, that your Method of Delivery may affect what your viewable resolution is. For example, when using a DVD player on a Full HD projector, the maximum resolution will be DVD (720x480).
Short Throw is related to the distance the projector must be from a screen/scrim/etc. to get the desired size. Many projectors will require 15-20 feet to get a life sized projection. A short throw projector can accomplish the same size with less distance as little as 10 feet or less. If your space is limited for projector to projection location, then a short throw projector or lens could be your solution.
Rear projection is often standard on a projector. It is a function that horizontally flips the image so that it can be projected on a screen or surface from behind. When viewed from the front, the image is then in the proper orientation.
The most economical way to find a projector is to search online. Ebay and Craigslist, for example, can yield very good deals on projectors. One significant consideration when buying a used projector is bulb life. Most projector bulbs will last somewhere between 1000 and 2000 hours. (Much older projectors are often in the 1000 hour range category) Bulbs can be expensive, so find one with very low hours or one that you can replace the bulb and still stay within budget.