Do I need to get the projector first? (1 Viewer)

[MarkDD]

Sometime this summer I will be building a home theater in the basement. I plan on buying an LCD projector this fall.

How do I know where to leave a hole for the projector and where to run the wires? I know some projectors come furinished with wires so would I be duplicating effort if I ran a set myself.

Or is it better to get the projector now?

I was thinking about the sony hs10 or the panasonic l300u. However, I was hoping by this fall another batch of new models would be out.

Thanks much.

 

[Neil Joseph]

First you need to determine the exact projector you want. This will determine what screen sizes you can achieve in your room. Each type of projector has a different throw and will yield a different screen size, depending on how much zoom you use. After committing to that, then you go ahead with the wiring and placement/mounting.

There was a thread a while ago where someone committed to a Sony HS10 and before buying it, he wired his HT for it. It has a longer throw than the average projector meaning you ned to mount it further back from the front wall to get a certain screen size. Then, he had second thoughts and wanted to get a different projector. Only problem is that from that mounting location, the image would be too big because it was a shorter throw projector and he already had the screen in place.

 

[MarkDD]

That is what I was afraid of. So what happens when I upgrade? Do I rip out the ceiling drywall and remount the new one?

Do people ever do a drop ceiling in the center and drywall around it for future upgrades?

 

[Glenise]

My basement has ceiling tiles installed.
The installer mounted chains in the ceiling.
If I get a new projector, I'll just move the existing tiles that already have holes for the chains to go thru and get someone to remount the chains in the ceiling.

 

[Neil Joseph]

To give you a little hope, many of the digital projectors (they have zoom capability) will yield an image of 100" diagonally (16x9) from a mounting distance of 11'- 12'. If you plan your mount around the 11.5' mark (assuming you want that sized screen of course then you should be pretty safe even in the future.

 

[MarkDD]

Thanks Mr. Joseph. I may just leave a 1X3 cutout in my ceiling at the 11-12 foot mark.

Let me ask you one more question.

I was planning on waiting till the fall to get the projector because I was hoping the new lines would be out.

My hang ups are:
1. l300u has no hdcp (will I be able to view a HD signal in the future)
2. hs10 and the sound factor, the supply issues and reliablity.

Should I build the theater and wait for better models or buy now and have to upgrade in a couple of years?

I would like to keep this projector for a while and do not want to be left out in the cold.

 

[Jay Mitchosky]

First you need to determine the exact projector you want. This will determine what screen sizes you can achieve in your room.

Alternatively you should consider your room layout and seating distance first, and select the appropriate screen size based on desired viewing angle. Minimum is 30 degrees, but other standards call for 35-40 degrees. With the necessary screen size identified (width and aspect ratio) you then need to consider projector specs. Projector throw distances (distance from lens to screen) are typically expressed in a range of multiples of screen width. So a projector with a minimum 1x and maximum 2x (to use easy numbers) throw would require 8-16' distance from the screen for an 8' wide screen size. If you're seated at the 12' mark chances are you don't want the projector above or in front of you. If a projector has too short a throw this may be a limiting criteria. You'll need to balance specs and performance to achieve what you want. Likewise if you demand that the projector must be flush mounted to the ceiling as opposed to hanging down you'll need to consider projectors that have optical lens shift that allow placement above the screen.

Installation issues aside you will also need to consider the range of screen sizes a projector is spec'd for. If you want (and can accommodate comfortably) a 110" wide screen but the projector is not recommended for sizes greater than 96" you'll need to change something. Either the projector type, the screen size, or the screen gain (get one that has higher gain for more light amplification, but beware of the detrimental image effects with fixed pixel projectors).

Personally I would recommend starting with screen size based on viewing angle and selecting a projector based on its capabilities and your installation preferences. If you start with a projector that determines a screen size that is too small (ie. delivers a viewing angle less than 30 degrees) you may be underwhelmed with the result.

Bottom line is pre-planning cannot be underestimated. What I'm in the process of doing is going through interations of room design and drafting things to scale to see how it all works out. My seating distance allows for a 96" wide (110" diagonal) 16:9 screen. That's a pretty reasonable screen size that delivers a 35 degree field of vision and can be accomodated by most of the current crop of projectors (will be a FireHawk with 1.35 gain). That said I also demand that the projector be mounted behind me. That pretty much takes out the new Marantz; despite how cool it is there is a very short throw that would have it mounted almost over my head. Can't live with that. Alternatively, the new Sharp 10000U sounds amazing and has a nice, long throw distance but it cannot be mounted higher than the top of the screen. This means the center of the lens will be 19" down from the ceiling - that leaves a very large white projector hanging in midair which aesthetically doesn't work for me (functionally as well as there will be casual seating behind it that will be affected). Another one bites the dust. Right now I'm really interested in the new Dwin TV3 as it offers a) a reasonably long max throw at 2.1x, and b) includes a lens shift feature that allows flush mounting to the ceiling. I made a spreadsheet that calculates screen size based on desired viewing angle and seating distance (including vertical screen placement based on ceiling height and eye level) if you're interested - just shoot me an e-mail.

--Jay

PS. When considering throw distances I would suggest not planning for mounting at either end of the projector's extreme range. For example, on a 2x throw projector for an 8' wide screen if you place the lens front at 16' you have zero room for error in your mounting. If you need a little extra zoom for proper setup and you're already at the limit you're screwed. Plan for a little bit of wiggle room. I have heard that it is recommended to mount the projector towards the end of its range as it more evenly distributes the light output across the screen. Don't know how true that is but intuitively it makes sense.

 

[Darren_T]

Deleted

 

[MarkDD]

Thanks for the detailed opinion Jay.

I went to projector central and did a quick throw calc.

For the HS-10 I put in a 8 foot wide screen.
It spit out this:

Distance to Screen Range: 4.9 ft. - 46.3 ft.
Screen Size Diagonal Range: 40.0 in. - 300.0 in.

16:9 Image Size 111 in. (diag), 54 in. (height), 96 in. (width)
Distance to Screen: 13.5 ft. - 17.0 ft.

I was planning on having the first row of eyes at 11 feet and the second row 4-5 feet behind that.
According to this calc, I am 2.5 feet too close.

Question: why would I not want the projector above my head? Is it a noise issue? I have a 24 long by 16 wide and 8 high foot room. My main worry for the mount is heat buildup and noise.

I do plan on having a casual area in the back with high tables and bar stools on a 8 inch riser. (maybe I got that casual seating idea from Jay).

 

[Neil Joseph]

The room specs makes recommending a specific projector easier.

With the first row at 11' and the second row at 15', one of the limiting factors will be the field of view of the first row. You do not want to overpower the front row viewers with a screen that is too large. At 11', I would hesitate going over 100" diagonal (49" x 87"). Once you determine the screen size, then you can work out the numbers for the different projector models you ae considering and figure out mounting distances. You have enough length, width and height in that room for it not to be too much of a limiting factor for you in choosing a projector for your HT design.

 

[Jay Mitchosky]

I do plan on having a casual area in the back with high tables and bar stools on a 8 inch riser. (maybe I got that casual seating idea from Jay).

...which I stole from last month's Audio Video Interiors. :b How did you calculate for your rise? Your room dimensions are very similar to mine. First row eyes will be at 12.5 feet with a 96" screen. I can't recall the distance to the row behind me. Based on sightlines for the back row the riser needs to be 15" high. I don't see how you will achieve clear sightlines (line up the 2nd row eyes with the top of the heads of the first row with the bottom of the screen) at only 8".

 

[MarkDD]

You have convinced me to buy the projector first. The basement is totally unfinished now so I have free reign on setup etc.

That 8 inch rise was what I heard from other sources. I just could not succum to dusting off my old calculus book to figure these calculations. And I always thought why would I ever use this crap.

Anyway, I know the ceiling is 8 feet high, my width is around 15 feet and I would like to keep it less than 24 feet long.

So I will have to look at mounting the projector at the back of the room, get the couches in place to determine my riser, get the screen up and test everything, then start building...

Thanks for your help.

 

[MikeWh]

Here is a calculator that I mentioned in another thread. Maybe people can find it useful here:

http://www.myhometheater.homestead.c...l#anchor_13194

 

[Jay Mitchosky]

That 8 inch rise was what I heard from other sources. I just could not succum to dusting off my old calculus book to figure these calculations. And I always thought why would I ever use this crap... get the couches in place to determine my riser...

You can start by sketching things out to scale. Grab a large piece of paper and draw out your room in profile at 1/4 to 1/2 scale. Once you've determined your screen size you place such that your front row eyes are 1/3 up from the screen's bottom. You need to measure yourself sitting in the chair of choice (and in the reclined position if applicable) from the floor to your eyes and floor to the top of your head. Position your scale reference at 11' from the screen and draw a straight line from the screen bottom to the top of the first row head and beyond. I actually made a scaled cutout of a person in a chair and moved it the proper distance from the screen and then up until the eyes were on the sightline. Because this is to scale you can then measure the necessary height of the riser. I cannot imagine planning out my theater without scaled drawings, including scaled furniture to move around.

So...

• Seating distance determines screen size
• Eye height determines screen's vertical position
• Sightline determines riser height
• Screen width determines projector position based on range of throw distances

Remember to not place the projector at either extreme of its range to allow for error in mounting.

 

[Jay Mitchosky]

That's a great link Mike provided, particularly as it references the different standards (THX at 36 degrees, SMPTE at 30 degrees). What it lacks is the ability to determine screen size based on location and viewing angle. It assumes you already have the screen. Most installations will probably have the viewing distance as the limiting factor and thus the screen should ideally be based on that.

 

[MikeWh]

[deleted]

 

[MarkDD]

Now all I need is for one of you to tell me to buy either the l300u or the hs10.

 

[MikeWh]

I'd buy the THX1138:4EB. It has infinite throw and great luminosity (in fact, almost everything appears white). No rainbowing. No pixelization. No CRTs to burn out. No bulbs to replace. Can also go through the back of people's heads. Virtually no noise. Unfortunately, requires PAL, 230V/50Hz.



Sorry. Just thought I'd humor myself. That's easy to do, as you can see.

 

[MikeWh]

Jay--

I checked that calculator link again, and I think it actually is doing what you want.

It's not totally dependent on the screen size. Whatever screen size you enter will effect the "Results" section (as expected), but below that section, it provides the optimum screen sizes for the THX and SMPTE viewing angles. Doesn't that do what you want??

 

[MikeWh]

Mark--

FWIW, for the 11' first row, the calculator provides:

for a 30°(SMPTE) FOV, screen should be 70.7" wide, 81.2" diag. (16:9)
for a 36°(THX) FOV, screen should be 85.8" wide, 98.4" diag. (16:9)

If you choose to go with the THX standard, then plug 98.4 into the "Diagonal Size =" field and recalculate.

The max THX viewing dist (26°FOV) is 15.5'. If your second row can accomodate a chair giving a head-to-screen distance of 15.5 feet, then you're good-to-go. If you need more leg room for the back row, you'll need to increase screen size, which in turn spaces out the numbers for recommeded and max THX viewing distance. This also pushes both rows back further in the theater, so you have to see if that'll work for your HT design.