[starion156]

Hi guys I am hoping some one can give me a little advice on the set up of my new projector system. I am new to this and this is my first projector.

I purchased an Optoma Themescene HD81 which arrived just before xmas. I ordered a screen as part of the package along with a ceiling mount for the projector. The ceiling mount and screen both came from Optoma.

I have ceiling mounted the screen and projector. The screen is 106 inch and I had expected the ceiling mount to set the projector at the right height to suit the screen. However when the projector is level the image is about 6inch below the bottom of the screen (this is with the projector installed the minimum distance from the screen and the screen fully down). This means I have to tilt the projector up to get it to line up with the screen.

Also as the projector does not have straight sides I wondered if there was an easy way to ensure that the projector lens is parallel with the screen. I can adjust the screen left or right to compensate if the projector lens doesn’t quite line up with the centre of the screen.

I cannot get the projector image to fit the screen no matter what I do, it is like the image is not 16x9. I am guessing this is something to do with not getting the lens parallel to the screen. Also the projected image size changes depending what is being watched, eg the sky menu is very wide, sky1 HD is narrower and Sky HD1 is nearly as wide as the menu. Add the fact that the image size does not fit the 16x9 aspect ratio of the screen and you are forever adjusting the projector to suit what you are watching. There is obviously something not quite right with my setup so any pointers would be much appreciated.

Also does any one know if the HD81 does 1:1 pixel mapping. I have connected my pc via HDMI port 2 and can’t get a sharp image (the text does not look crisp and sharp as you would expect) even set to 1920x1080 also the manual says that it supports 24 Hz refresh but there is no 24Hz option is my display properties is there a third party display diver out there?

I have to say as a whole I am very impressed with the image quality and know there is a lot more to come once I have sorted the setup and even more when I find the money to get it properly calibrated. I have only tried Sky HD at the moment. I watch HD-DVD via my xbox 360 which is not hooked up yet and Blu-ray via my PC which I am having a few problems with.

[Gary Lightfoot]

Ceiling heights vary as do projectors image offsets so it's not always possible to make a lens mount for every situation.

If you can get the projector close to the ceiling that would help, but it may mean modifying the existing ceiling mount or making your own unless you can get the screen higher to fit where the image falls.

The angled sides of the image are there because you have tilted the projector up, so the top is further away from the lens than the bottom. You can use the projectors keystone facility but although this can straighten the sides it can sometimes introduce some odd image artefacts so most people try not to use it and I wouldn't recomend it.

Without seeing the images on your screen it's hard to tell what may be wrong, but with normal DVD and tv transmitted stuff which is standard definition, I would try to use a projector mode which makes them all fill the screen. If any mode is bigger than the screen then the projector is too close or zoomed too close. If you use the projectors own output (if it has it) without any inputs active, you should be using the whole panel of the pj, and then use that with the zoom to fill the screen. It will be easier with the pj being square first though, so sort out the ceiling mount first.

I think I sw someone having a similar problem with the HD1 and PC not too long ago, so try the search and see what comes up. Powerstrip may be the program you are thinking of which can give you custom timings and resolutions.

HTH

Gary

[patt]

Hi just out of interest how bright is you hd81 as mine is just so dim on a 100" screen with a 1.2 gain [ funny my hd72i is a lot brighter ]


also m8 try image shift on the hd81 to bring the picture up, look in the menu

[Gary Lightfoot]

Hi Patt,

Do you have the iris closed down at all? That would dim the image..

I think the image shift is electronic so would move the image up and crop the top off of it since there is no optical lens shift.

Gary

[starion156]

Thanks for the info...The projector mount is only about 200mm from the ceiling using an Optoma projector mount. The screen is an Optoma 106inch screen matt white cant find it listed on the website as they only list the motorised screen in Graywolf II format. Whilst I would agree you cant make a projector mount to suit all occations you would have thought that the Optoma ceiling mount and projector screens would be matched so that when fitted at the right viewing distance the screen would be low enough assuming both mount and screen are at the same mounting heights....but I guess that would be far too easy. Will have to look at what I can do to modify the ceiling mount.

Getting the projector parallel in the vertical plain is not too difficult as the base of the projector is flat and so a level will do the trick. Its getting the projector parallel to the screen in the horizontal plane which is the problem (the projector body is curved so no striaght edges to get the angle from). I am hampered at the momment as the screen is far from flat...I have contacted the dealer but have to wait till Optoma are back in the new year before I can get it replaced. I am considering asking if they can reduce the size down to a 92inch as I think this size is more suited to my room. Would love to go to 96inch but this seems to be an odd ball size for a projector screen.

As for the brightness...I would agree the image could do with being a little brighter although zooming the image to 92inch doesnt seem to make that much difference.

Mike

[starion156]

I tried the image shift but realised when I connected my pc that the image shift does not move the image but crops it instead.

Also image shift settings are not saved so u have to re-enter them each time you turn on the projector.

I guess you really do have to position the screen and projector bang on if you want a good image.

Mike

[Gary Lightfoot]

Hi Mike,

You might be able to get the pj central to the screen by using a piece of string. Use a length going from one top corner of the screen to the ceiling and make a curved mark where you want the pj to go, then do the same from the other corner making sure the length of the string is the same and make another mark on the ceiling. Where both marks cross is where the center of the lens should go. Place the pj flat on the ceiling so you can see where the pj body is in relation to the lens and mark the ceiling so you can get an idea where the mount should go.

With fixed offset projectors you're absolutely correct that positioning is critical for the best image.

Pull down screens do tend to ripple a bit but sometimes adding a little weight can solve that (but not always).

Gary

[patt]

Hi gary think i have found the problem the bulb, the picture just goes off after about 2 minutes lamp light flashes, if i turn it of then back on it does the same picture pulses then goes off only done 3 hours this must be why the picture
went dim

thanks


starion156 image shift settings are saved if you save a new format look in menu m8

[Gary Lightfoot]

Hi Patt,

Going to get it fixed under warranty?

Gary

[patt]

Hi. no m8 taking it back only pick it up on friday
got it for 1695 ex demo which i thought was a good deal,they said it had been returned to optoma had new bulb all reset and cleaned up,
if they can,t replace it will have a refund, what a pain

[starion156]

Hi Patt,

Sounds like you got the same deal as me. Did you get the pj from Audiovison by any chance. I must say not notice that with mine. image is pritty brite most of the time but then I do have the auto iris on at the momment and you can some times notice the jump when it opens and closes, thankfully not as often as I have read about.

Any way let me know how you get on because I need to return the screen which as well as suffering from the ripple effect which sounds like somthing that is easy to cure it has a crease runing horizontally about 12 inch from the bottom and and the casing is all marked like it has come into contact with water of some other liquid.

[starion156]

Hi Gary,

Thanks for that tip I will give it ago.