a little confused about projector placement (first proj setup)

[Aharami]

This is my basement finishing plan

Seating area will most likely be around or a little forward of where the stairs end. So seating will be 12-16' from 15' wide wall. Since Im finishing this basement from scratch, I have complete control of lighting, and project placement. Projector will have to be ceiling mounted. Ceiling height will be 7' when the basement is finished.

The projector Im considering is either the Panasonic PT-AE4000U or the Epson 8100. I was reading thru this review on projectorcentral and it says

you lose up to 41% of potential light output if you set the 2.0x zoom lens to the maximum long throw position (smallest image from any given distance).

The following are my understanding. Correct me if Im wrong. Im assuming Im supposed to leave the projector's lens at the lowest zoom setting (widest angle) to get the highest lumen output. Having it at the widest angle will mean that the projector will have to be placed closer to the screen.

I was playing around with the projection calculator for the PT4000U. I know I want a 100" screen on the 15' wall (next to the 3'7" door). Leaving the screen slider at 100", if i slide the zoom slider all the way down to 1.00X, the throw distance goes up to 19', and I get image brightness of 16fL. If I move the zoom slider up to 2.00X, throw distance goes down to 10', and image brightness goes up to 27fL. The complete opposite to how I understand this to work. Well I get that the closer the proj is to the screen, the brighter the image, but why does moving the zoom slider up bring the proj closer to the wall?

So confused. How far should I place the projector from the 15' wall for best brightness and image quality?

 

[Aharami]

anyone?

 

[YOyoYOhowsDAjello]

Ok, so the farther back the projector is, the larger the image gets.



So at 10 feet back, the range of image sizes are

53" minimum zoom (1.0) 57fL
to
100" maximum zoom (2.0) 26fL



At 19 feet back, the range of the image sizes are

100" minimum zoom (1.0) 17fL (about 40% less output... as described in the projector central review)
to
193" maximum zoom (2.0) 7fL


So, the "zoom" makes sense when you keep the distance from the screen constant. More zoom = a bigger image.

For any given screen size, when you move the projector back farther, you'll have to turn to zoom down since the image would get bigger if you kept the zoom level the same.

So, in order to get the brightest image, you want to keep the zoom level high and keep the projector closer to the screen. In your planning, I would suggest giving yourself some wiggle room and not go right up to the edge of what the calculators tell you are the limits of the range.

Does this make sense?

 

[vshah]

from my own research on this it seems to be that the longer your throw/further away you put your projector, you'll have less light output but more contrast. the closer/wider you make it, you'll have more light but less contrast.

in practice, put it where it will work best within the range in terms of wiring/location of seating etc. you said yourself, your room will be light controlled.


darn, beat by yoyo. i really thought i might be before him in this thread. but he has the AVHT chip in his brain so i can't really compete

 

[YOyoYOhowsDAjello]

from my own research on this it seems to be that the longer your throw/further away you put your projector, you'll have less light output but more contrast. the closer/wider you make it, you'll have more light but less contrast.

in practice, put it where it will work best within the range in terms of wiring/location of seating etc. you said yourself, your room will be light controlled.


darn, beat by yoyo. i really thought i might be before him in this thread. but he has the AVHT chip in his brain so i can't really compete

My chip must be off today, it took like 7 hours

 

[Muadib]

Screen selection goes along with this, IMO. Different material can affect both gain & contrast. http://www.da-lite.com explains this pretty well. They used to have a walk though, that gave you an idea of what you needed, but they appear to have removed it, and replaced it with some sort of software. Even without the software, odds are you will learn something.

 

[vshah]

in terms of screens remember that, basically, the higher the gain, the narrower the viewing angle.

again, since you have a light controlled room you might want to go for a gray screen that will increase your contrast

 

[Aharami]

thanks for the responses. the easiest proj placement would be around 17' since the A/V units will be stored under the stairs, and a 17' distance would align the projector to around where the A/V units will be. But that seems to be out of the green zone in the yellow box. So Im thinking a 11' throw distance at 1.8x zoom. But that will place the projector right in front of the seating area. How loud are these projectors? Should I placing it so close?

The reason why Im trying to figure out the placement area before I even get the projector is because I have to install a ceiling outlet to power the projector and would like to have it close to where the proj will be, thus minimizing cables on the ceiling. Or is is better to get a long power cord like this one and run it along with the video cables?

I havent even begun researching screens yet. I know I want to do a DIY screen for sure - either painted on the wall, or stretched fabric on wooden frame. Havent done enough research to find out which one yields better results. vshah, can you provide some links that talk about the throw distance the contrast?

 

[vshah]

ceiling power outlet is a good idea. i've had a ae700, an ae900, and an ax200. all have been virtually silent, definitely inaudible if something is playing. i wouldn't worry about it. i think yoyo has the 4000u so he should be able to comment specifically on that one.

also, one nice thing about having the projector above or slightly in front of the seating is that you don't get blasted in the face by light when you stand up. you may want to construct some form of box to hide all the wires etc.


I'll try and find you the links when i get home, they were from avsforum which is inexplicably blocked at work.

 

[YOyoYOhowsDAjello]

The AE4000U is quieter than the AE900U.

I have it on a stand in the back of the room. I can hear it in quiet parts of movies if I listen for it, but I don't find it distracting.

 

[Aharami]

i just thought of something which makes the ceiling power outlet less desirable - no surge protection. If I run the long power cable thru a different cavity from the video cables, I shouldn't get any interference, and I'll be able to surge protect my proj along with the rest of my A/V equipment

 

[Aharami]

The AE4000U is quieter than the AE900U.

I have it on a stand in the back of the room. I can hear it in quiet parts of movies if I listen for it, but I don't find it distracting.

sweet! YOyo, give me your thoughts on the AE4000U. The main reason Im considering this over the Epson 8100 is the frame interpolation/120Hz. After living with my Samsung LN46A650 120 Hz tv for a while, I find 60Hz to be very jarring. How effective is the frame interpolation on the AE4000U?

 

[vshah]

the brightness vs. contrast thing basically comes down to the effective aperture of the lens at various zoom levels, and the difference is small, maybe even unnoticeable. your choice of screen material will have much more impact than zoom level on your contrast. will update this in the evening with those links...

here's a yoyo post: http://forums.anandtech.com/showpost.php?p=28945899&postcount=17
regarding the 4000u's "frame creation" modes.

 

[YOyoYOhowsDAjello]

sweet! YOyo, give me your thoughts on the AE4000U. The main reason Im considering this over the Epson 8100 is the frame interpolation/120Hz. After living with my Samsung LN46A650 120 Hz tv for a while, I find 60Hz to be very jarring. How effective is the frame interpolation on the AE4000U?

I've been bothered by the low frame rates used in film for years now. Slow / medium speed panning gives me headaches in the theater and to some degree in my home theater.

Perhaps I'm destroying the director's intention for film purists, but I will not buy another projector without this feature now that I've seen it in person. I have it set on Mode 2. Occasionally it will take a fraction of a second for the frame interpolation to engage after a scene change, and occasionally there will be an odd artifact due to some complex screen motion (like text scrolling over the screen in one direction while the background moves in another), but 99% of the time I'm very happy with it.

Mode 1 is even less objectionable. Mode 1 smooths things out a bit, and Mode 2 looked a bit odd to start off with, but there were some definite things that I liked about it. It only took me about 2-3 movies to become accustomed to the "smoother" motion of things that originally looked odd.

Going back to no frame interpolation looks like a stutter-fest now.

I'm incredibly happy with this feature and along with much better black levels, and better colors, it tops my list of things I like the best about my upgrade.


The only thing I have to complain about is that I got a dust blob on the projector with only about 100 hours on it. A few minutes of effort and I was able to follow a guide on AVSforum to getting rid of the blob though. Now that I know what I have to do in the future, I'm not concerned about dust blobs anymore, so I'm very pleased with the purchase.


Let me see if I can find my original comments on the thing from AVSforum...

http://www.avsforum.com/avs-vb/showthread.php?p=17575587#post17575587

 

[Aharami]

thanks! to both of you