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91" screen. The top is 11" from the ceiling. PJ will be mounted on ceiling. Lens will be approx. 8" from the ceiling. Throw is 10'6" but could be closer if I choose. The PJ is perfectly perpendicular to screen.


On pjcentral it shows me a 15" demarcation between lens and top of screen. http://www.projectorcentral.com/Mits...ulator-pro.htm


If there is no lens shift and keystone is undersireable, how exactly do you DLP guys get these things dialed in? I just don't understand.


Thanks!
 

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If the center of the lens is 8 inches from the ceiling and the offset shown by the calculator is 15 inches, the top of the screen where the image will show should be 23 inches from the ceiling. Throw does not matter, vertical height of screen is how offset is calculated.
 

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At 91 inches, the vertical height of your screen is 45 inches. Add 11 inches to that and the bottom of your screen is 40 inches off the floor assuming you have an 8 foot ceiling. Without knowing what your seating plans are, you are probably hanging the screen higher than what you need (or want to). In general, the height of your eyes should be 1/3 to 1/2 of the way up the screen when seated in your normal viewing location.


Once you have your screen set at a lower height, you can dial in the screen by adjusting how low you place the projector from the ceiling.
 

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Thresher what's your ceiling height? Based on that with the other figures you supplied we can tell you where the screen will be mounted. You will more than likely have to move the screen up or down. I have mine in a basement theater with a 7' 3" drop ceiling projected on a 108" screen. The projector's lens is 12' 11" from the screen and the "center" of the projector's lens is 4 1/2" from the ceiling and my screen is about 18" off the floor. My HC1500 is angled up very slightly, so slightly there isn't any bowing of the image. Probably angled up about 1/2 an inch.


I had the same concerns coming from the Z2 with lens shift. Heck with the Z2 my screen was 104" and now I've built a new one that's 108" with the HC1500.


Your 91" screen would easily fit even with my basement's 7' 3" ceiling.


Also download Mitsubishi's calculator http://www.mitsubishi-presentations....rjcalc_v18.zip


Just plug in the following


Projector

diagonal

ceiling

pole


The rest will fill in with the min projector distance at the bottom.


Here's what mine looked like with the Mitsu calculator Attachment 128320 . Remember mine is angled up about an 1/2" which rose the image about 4 or 5" over the calculator's 12.8" figure to 18". It only takes a small amount of of angle to position the image up or down a lot of inches without bowing.



 

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Quote:
Originally Posted by Thresher /forum/post/15436883


91" screen. The top is 11" from the ceiling. PJ will be mounted on ceiling. Lens will be approx. 8" from the ceiling. Throw is 10'6" but could be closer if I choose. The PJ is perfectly perpendicular to screen.


On pjcentral it shows me a 15" demarcation between lens and top of screen. http://www.projectorcentral.com/Mits...ulator-pro.htm


If there is no lens shift and keystone is undersireable, how exactly do you DLP guys get these things dialed in? I just don't understand.


Thanks!

I will be mounting my projector in the next couple of weeks after remodeling the room it will be in. I am going to ceiling mount my projector then dial the picture in on the wall.


I expect that I will need to adjust the drop tube length to get the picture where I need it. Once it is there and as good as I can get it, I will place the screen against the wall and move it around until is lined up with the projected image and mark the screen for mounting.
 

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Ah, that could be a problem. If that's the case then he's going to need an LCD with lens shift. I don't know of any reasonably priced DLPs with lens shift. Otherwise it will be pretty hard to find projector with the same drop as his Z2 with lens shift engaged.
 

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I'm using an HC1500 in a room with a 7' ceiling. I made my own mount which keeps the pj very close to the ceiling and have it angled up slightly so the top of my 110" diag screen is 6.5" from the ceiling. The image keystones very slightly, only about an inch on each side, and it's only noticeable if you look for it at the edge of the screen.
 

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Quote:
Originally Posted by Thresher /forum/post/15482267


Here is a pic of my setup. Ignore the 8" screen drop, that is to the top of the border, it is 11" to the top of the screen.


I have a similar situation with my HD1000. The room set up is essentially the same as yours although I have a cathedral ceiling and my distances are a tad longer. I tried everything and finally found the answer (without using keystone which should be avoided). The solution was to optimize the picture and move the screen up and down in stages. The picture was centered of course simply by placing the projector dead center. The problem was up and down.


As you can see by the attached photos, the solution was to hang the screen and move it in slight increments up or down (the screen is a Carada 106" BW)

until it was just right. This was accomplished with hooks and turn buckles. It would be almost impossible without lens shift or keystone to hang it on the wall just right. The turnbuckles made it a snap. I hope the pictures come out so if they don't I'll try again in another post.


 

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Quote:
Originally Posted by milacqua /forum/post/15482810


I have a similar situation with my HD1000. The room set up is essentially the same as yours although I have a cathedral ceiling and my distances are a tad longer. I tried everything and finally found the answer (without using keystone which should be avoided). The solution was to optimize the picture and move the screen up and down in stages. The picture was centered of course simply by placing the projector dead center. The problem was up and down.


As you can see by the attached photos, the solution was to hang the screen and move it in slight increments up or down (the screen is a Carada 106" BW)

until it was just right. This was accomplished with hooks and turn buckles. It would be almost impossible without lens shift or keystone to hang it on the wall just right. The turnbuckles made it a snap. I hope the pictures come out so if they don't I'll try again in another post.

Too bad the pics did not come out very well. Let me put a couple more up. I know I've got to paint the turnbuckles black and do a few touch ups to the projector mounting board but now that everything is dialed in I can do the cosmetic work later. Remember, the secret is to get the projector high enough because it shoots down and at a fairly severe angle. You have it about as high as it will go in your room so you must do the adjustment with the screen as I did.


 
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