Saturday, February 09, 2008

Choosing Components for Front-Projection

Now that my mancave has evolved into a theater, I have had to expand my research into front-projection systems. I use the word system because that’s exactly what it is. There is a projector and screen of course but there is a sometimes forgotten element - the room. Before you spend one dime, you have to know the exact conditions of the room; light control, mounting positions for projector and screen, wall and ceiling construction and of course, throw distance.

Ideally, a theater should have total light control. You should be able to make it totally dark. This includes light leaks around the entry door which can be considerable. Windows can be covered with blackout curtains but the best method is some sort of panel or shutter. In my case, I used acoustic panels to both cover the windows and act as sound treatment. To seal the door, I used some thin rubber strips in the door frame and a sweep for the door’s bottom edge. Not only is light sealed out but sound transmission through the door is nearly eliminated.

My next order of business was choosing a screen. I knew I wanted a fixed-frame screen for a few reasons. Since the room is a theater, I don’t need to retract the screen at any time. I also wanted a wide, light absorbing frame. Lastly, the highest image quality comes with a perfectly flat screen. I chose Carada based on excellent reviews, value and design. Their Criterion Series screens have a 3.25” wide by 1.5” deep extruded aluminum frame covered with a velvet-like material they call “Black Hole Trim.” They are not exaggerating about this. It really does absorb all light. I’ll be able to take the image right to the edge when I have the projector set up. This frame is extremely stiff. The screen can’t help but be perfectly flat. The mounting system allows the screen to hang on a bracket so if the wall isn’t flat (mine certainly isn’t) the screen still will be. The screen material is also important. Carada offers three: high-contrast gray, cinema white and brilliant white. The gray has a gain of .8 and will improve contrast at the expense of light output. Black levels will be very good with this material. Cinema white has a 1.0 gain which means it will be completely neutral. Brilliant white (my choice) has a gain of 1.4. I do like bright whites and 1.4 is not such a large increase in light output. Given that I measured .02fl on a 0 IRE field from an AE1000, a gain of 1.4 will give me .028fl, still quite black!

My choices in projectors started with price. I wanted to spend under $3000. Fortunately, there are many excellent models to choose from. The top models from Epson, Panasonic, Sanyo and Mitsubishi all have just the right attributes for a small theater like mine. Using the excellent throw distance calculator on, I determined the Panasonic AE2000U could project a 92” image within my possible throw of about 11 feet. I also thought very hard about mounting options. Certainly a ceiling mount would work but I have some obstacles. The walls in my house are old-world plaster making stud finding a real challenge. I certainly would need to attach a ceiling mount to the joist for safety’s sake. I also have an 8’6” ceiling in the theater. Putting the projector that high would be too far above the screen top for my taste. Even though the Panasonic has a large vertical lens shift range, I’d rather keep the projector closer to screen center for better uniformity. I decided to go with a shelf about 6 feet high. The shelf gives me another bonus: adjustability. To achieve the best image, you need to have the projector and screen perfectly on plane both vertically and horizontally. You can do this with a ceiling mount but you have to be sure to buy one that allows pitch, yaw and rotation adjustments.

There are of course other considerations with projector models, namely, black level quality, color accuracy, image clarity and light output. While the SMPTE standard for cinema is 16 foot-lamberts with no film in the projector, many professionals are recommending 20fl peak. The Panasonic AE2000U can achieve this. By using the formula: fl=(lumens/screen area in square feet)*gain, a peak reading of 402 lumens with a 92”, 16:9 (25 square feet), 1.4 gain screen yields 22.5fl, more than enough. The color accuracy is certainly there with the 2000 and black levels are superb. This projector uses the same D7 C2fine panels as the Epson Ultra-Black series. Black levels I measured from an AE1000U were the same as a good plasma panel.

My final consideration is the room’s construction. As I said, my walls are plaster and therefore more difficult to work with than drywall. I have the added challenge of mounting the screen over a window. The window is totally covered with black acoustic panels and I’ll be covering the rest of the wall behind the screen with black burlap. This will absorb any light that shines through the screen material. These reflections can alter the color if your walls are not perfectly color-neutral. Many installers use either flat black paint or black carpet to do solve this problem. To find studs to support the projector shelf and screen brackets, I’ll drill small holes. The location for the shelf is right over an electrical outlet. There is a stud on one side or the other which I’ll confirm by removing the wall plate. Once I confirm the stud’s location, I’ll use 3.5” lag bolts to secure everything.

All this information is out there in various places on the internet. Hopefully, this will tie together a few things for those of you interested in going to front-projection. Prices and quality have never been better and you don’t need a huge room to have a huge screen. I’ll never have to go to the movies again!

Thanks for reading and enjoy the view!

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