[MaxCast]

I'm wiring a new room and was wondering if I ever wanted a projector how do you determine the distance to the screen?  Are they adjustable?  Anyone know the l x w of a 100" screen?

[zybar]

I'm wiring a new room and was wondering if I ever wanted a projector how do you determine the distance to the screen?  Are they adjustable?  Anyone know the l x w of a 100" screen?

A general rule of thumb has been to sit at least 1.5x the diagonal of the screen.

The actual width and length of any screen is going to be determined by its diagonal dimension as well as the width of its borders.  Most screens have between a 1" to 4" border all around.

With the newer 1080p pj's, you could probably sit closer if you wanted to, but that will come down to personal preference.

Hope this helps a bit.

George

[MaxCast]

Thanks George, so for a 100" screen I need to place the projector 150" from the screen.

As far as dimensions, I was hoping someone had a 100"er and knew the lxw 

[Bob in St. Louis]

Hey Rich,

A 100" screen (16:9) would be 49" tall by 87" wide.

"Throw distance" as it's called is the measurment from the lens to the center of the screen. Yes, it is adjustable, just like the lens on a camera. Some projectors (PJ's) have manual zoom (like a camera), a few have an electric motorized zoom.

If you see a PJ you're interested in, here's a neat website and "calculator" to determine all of the applicable (but VERY necessary) numbers regarding whether or not a PJ will work in YOUR room. These are NOT one size fits all:
http://www.projectorcentral.com/Sanyo-PLV-Z2-projection-calculator-pro.htm

{To use the calculator, you've got to enter a PJ make and model, for this demo I used mine}.

Bob

[ted_b]

Also, keep, in mind that a projector's "sweet spot" is somewhere between its minimum throw and maximum throw, each distance trading issues like brightness for black level, etc.  Each pj manufacturer will have slightly different throw lengths (and subsequent vertical shifting needs) for 100" 16:9 screens, so George's rule is a general one, but make sure you check with the mfg.  My 110" setup Samsung digital pj sits at about 14'4" but my older Runco CRT sat much much closer.

[superchad]

There are Projector throw calculators that work based on your room conditions and lumen output, this may be of use as I looked here and other areas  when I installed my Projector, cheers.....................
http://www.projectorcentral.com/projection-calculator-pro.cfm

[MaxCast]

Thanks Guys. 

[Big Red Machine]

Hey Rich, you've seen my afterthought hushbox and hopefully can plan better than I did.  I was thinking early on that the noise of the PJ would not be problem with the volume level of a flick but I was wrong.  And then the heat from bodies and a PJ fan, especially after a double feature, really heat up the space and make it uncomfortable.  So maybe you can plan ahead for some type of hush box, even if it does not use the glass on the front, the meer removal of the hot air and some muffling of the noise is very helpful.

Now most of my HT buddies put their PJ's way on the back wall to keep the box out of the way and unobtrusive.  But then they trade off brightness and black levels, etc.  Something to consider.

[superchad]

 While I can hear my Panasonic Pro (720p LCD) it really doesnt draw your focus to it, if it does lets face it the movie sucks but I would never trade off ideal picture for a bit of fan noise only heard during the quiet scenes, if your room is of average size even having unit on shelf in rear will be somewhat close and then you have increased bulb use to get a bright picture and louder fan noise to cool the brighter bulb setting so it makes little sense to do this.
 This weekend I am installing a small one room AC unit in my cave, its 14X24 and in basement so it gets a bit warm and stale in there after a few hours af electronics and bodies giving off warmth. Being that I am in a walkout basement I am lucky I can retro fit this idea with ease but far to many cant and its a really big deal, a room over 70f gets old in short order. Nothing is perfect and Projectors certainly are not but you cant beat that emersive experience you get, far too many have this pretty adequate surround system and a comparatively wimpy screen size and I am still surprised more dont look into Projectors.