Optoma GT1080 Owners - Question!

[jetergr]

For those of you that have the Optoma GT1080, how does the projector handle 4:3 aspect ratio images? I'm looking at getting a 12x9 screen (4:3 aspect ratio) in order to fill up the whole screen. However, I read that this projector has a native 16:9 aspect ratio. Does that mean that the projector sends out black side bars, in order to accommodate a 4:3 screen?

Also - if I have a 4:3 screen, and want to watch a 16:9 image, the new image would obviously expand wider than the 12' screen. Am I able to 'zoom in' the 16:9 image so it would then stay within the 12x9 screen?

Thanks in advance for all the help!!

GR

[mgcfc]

Looking at the GT1080 myself. From what I can tell it an be set to handle 4:3 aspect and yes to do this it will have black side bars. However you could still have it setup to fill your 12x9 screen. It all depends where the projector is placed in relation to the screen. Using the calculator on Projector Central and setting aspect ratio to 4:3 and the screen size to 12x9 you have to mount the projector (assuming a ceiling mount) 8ft from the screen. Now the key to your ability to achieve this is you ceiling height. The GT1080 has a large offset and at that screen size the offset is 1ft 5" from the centre of the lens to the top of your picture. This means 9ft + 1ft 5" + say 2" to the top of the projector + the height of the mount say 6" = 11ft 1" ceiling height required to get a full 12x9 image.

[cspin]

Hey mgcfc,
I just put up my simulator enclosure and screen. My ceiling height is 9' 6" tall and my screen is 10' x 7'6" set up for a 4:3 image. I have a Benq MX631ST and just today went to set it up. I am mounting it on the ceiling, and yet the top of my screen is 2' from the ceiling. I did this to allow ceiling protection netting tapering back on an angle from the screen. Screen goes to the floor, which give me the 7'6" in height. I think I have a problem though with the projector I bought because the offset is minimal and the only way to get the image onto the screen is to either lower the project to 8' or less (not an option) or to use keystone correction, which reduces the image quality. Would going with the GT1080 help me out because it has such a large offset, or am I misunderstanding how offset works? I understand a projector with lens shift would do the trick, but those are expensive for short throw projectors, if you can even find one. Thanks!

cspin

[mgcfc]

cspin,

Do you know what the distance is from the ceiling to the centre of the projector lens when mounted using the mount you currently have?

To have an image 10' x 7'6" starting at the floor the centre of you lens would need to be 7'11" from the floor, based on this the mount would be in the range of 17" from the ceiling to the bottom (top mounted upside down) of the projector. If your mount is less than this the image will rise by the same amount off the floor. So if the ceiling to top of projector is 12" the bottom of your image will be 5" off the floor and by the same at the top running off your screen.

What is the issue with mounting the projector at the required level? It shouldn't interfere with your eyeline or swing. The only issue might be if you intend hitting from a distance less than 10ft from the screen in which case you may cast a shadow.

With the GT1080 the floor to centre of lens height would be 8'8" (9" higher than the MX631ST) but also would be mounted only 6'8" from the screen so little risk of shadows.

Hope this helps.

mgcfc

[gene438]

I have the GT1080 and mgcfc is absolutely correct. I actually run in 4:3 mode and my screen is actually only 9 x 11. I choose to set to the width of my screen and I offset to the top of the screen so that my black bar is at the bottom....this just looks more natural to me.....People who come over have never actually noticed that the image does not go all the way to the floor...so, don't get to hung up about it.

[Emptyshotgun]

So if I have 9 foot ceilings, can I mount the optima 1080gt and hit a 9x12 screen if I use keystone or vertical shift, or maybe tilt the projector up? Not sure if you can correct the lens to picture drop ratio with these methods. I ask because I like the price of the GT, but Would like to take advantage of as much of my ceiling height 9'1 with a projected image. Considering the benq 1085st too, but is a bit higher priced

[goodmatt78]

Benq had way less vertical offset. You will need a ton of keystone with the optima and that is bad for image quality.

[Psw757]

I'm getting ready to order a gt1080 and am having a heck of a time figuring out how for back the projector with need to be to fill a 7'6w x7' h screen. It is the net return pro screen. I have 11ft ceiling as well.

Thanks

[Joko]

It'll be short. I have the same pj. And my screen is 10' wide and I'd say 5' 8" away. Ceiling is 9' 8".