[Murilo]

I had a guy install my 8700 last week, right now my picture is almost square, its slightly trapezoid, the guy i noticed used keystone (2 points) to correct it. I put it back to 0 once I noticed, however it is slightly trapezoid, the top half spills over about half an inch, while the bottem half of the image is just filling up the screen. Should I move it to the correct position and have a perfectly square image? There is no obstruction, and its just 4 screws in the mount in my ceiling, no big deal, i could move the entire thing over, I really dont want to ask him to do it he thinks there is nothing wrong with keystoning and wont want to move it.


My question is, is it worth it for that slight of trapezoid image to move it over? Could I maybe make it worse? I just want opinion on what i should do?

 

[Murilo]

Or is the trapezoid image due to vertical alignment? I just looked at the manual and took measurements myself, the lens is about 5 cm below the top of the screen, where in the instructions say it should be 5-7 cm above the screen. I did not notice but there is a small beam infront going across my ceiling infront of the projector, but still the projector is definately well below it, I could at least raise it a couple cm up. What threw me off though is the top of the image is slightly to high for the screen, I notice the projector on the mount is slightly tilted upward, I cant seem to correct it, it just keeps tilting up. Tommorow I will give him a call and see what he could do. I know very little about installing so I am looking for any advice. Ideally I would like him to raise the projector a couple cm, I know that it could definately be raised up a cm or 2 above the screen, instead of a few cm below the top of the screen, and I also would like it so the projector is not tilting up. Is there any reason why its tilting up? Bad mount? Bad mounting job? The projector is just so sensitive to movement on this mount, and I cant keep it level, the backside keeps titling down thus raising the lens up a bit and moving the picture up.

 

[coverup]

I can only tell you that I installed mine and did so right within the nominal dimensions per the intatllation guide. I have no keystone and a perfectly 16x9 picture. I do think your PJ height will cause an issue for you if you can not get it up a little. Possiblly lower the screen too. Good luck.

 

[clubfoot]

Probably the easiest way to set it up is to level the projector, throw a 16X9 image on the screen the same size as you screen, and move the screen to the projected image. Remember also that the projector lens is offset from the centre of the projector so you will have to make sure you take that into account as well.

 

[Jeraden]

The trapezoid is because the projector isn't completely level. Since it has to be mounted a specific distance from the ceiling, if the top is wider than the bottom it means it was mounted too low and he has it point upwards slightly. Can it move any closer to the ceiling? If not, there isn't much you can do so there is no lens shift. Well, your other option is lowering the screen I guess.


Mine isn't level and exhibits the same trapezoid as you, top wider than the bottom. I just live with it and don't use keystone correction. To be honest, I can't even notice once a movie is playing. From my seated position my eyes are closer to the bottom of the screen than the middle of the screen. This in effect "fixes" the trapezoid problem slightly as the bottom of the screen is closer to my eyes than the top, which ends up doing offsetting the trapezoid problem and making it actually look square from where my eyes are. Maybe that doesn't make sense, but unless you actually see a problem while you are watching stuff, I wouldn't sweat it that much.

 

[Murilo]

I had him raise it about 2 inches tonight, right now though, I am only about 2-3 cm above the top of the screen, I am suppose to be 7 cm above the screen, I can only only lower my screen, about another 2 cm which I will get done wednesday.


There is still a slight trapezoid, the top part of the image is 2 cm wider then the bottem, I suppose thats not much, and I have a carada brilliant white screen with a black frame that absorbs the light, you can notice the light spilling on the top half onto the frame if you go right up to it. Standing a few inches away you cant notice it. Still I want to try to make the image perfectly square even though i wont be able to notice it nor do my guests, It still bugs me its not perfect, so I am gonna try dropping the screen about 2 cm, which is as far as i can drop it.