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Topic: Possible? Short Throw 4k ceiling mount with image flush to ceiling
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Joined: Aug 11, 2011
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Application: video wall art installation, residential installation, 3 projectors combined into one image

Desired: image near-flush with ceiling from ceiling-mounted projector

Ideally: with minimal shadow occlusion from viewers standing close to image

Factors: low ceiling (93"), viewers will be standing (not seated).

Needs:

• 4k UHD to 8k resolution

• Short or Ultra Short Throw (<10" desired, up to 36" acceptable if no occlusion)

• Ceiling mount, with top of image flush with ceiling (or, if nec., up to 12" gap acceptable).

• >90 fL apparent brightness (at throw distance for 74" wide image)

• not huge and heavy, <40 pounds

I just tried an Optoma P2 which is excellent image quality and pretty good brightness, is small and light, and very quiet -- except it has no vertical lens shift, and thus its offset is 10" plus the height of the projector plus the height of (custom) ceiling mount -- i.e. 15"-20" gap from ceiling, sadly, not acceptable.

I also spec'd a BenQ V7050i which can be closer to wall, and has a slightly smaller vertical offset, but it's not quite bright enough.

The other options I found were jumping from $4k to $25k which is acceptable if it's necessary - e.g.:

Sony VPL-VZ1000ES - quiet and very short throw but massive and heavy and also not bright enough

Dukane ImagePro 68100-4KSS-L (with a fixed short lens) - incredibly bright (more than we need), heavy and loud, and also needs 28" throw distance (vs 6" for BenQ or 18" for Optoma)

The Projector Central search tool doesn't show any other options for true 4k projectors with under 24" throw.

I would love any other recommendations!

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diagram

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Joined: Mar 28, 2005
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There are no ultra short throw models I have ever seen which do this. This comes down the the mechanics of the lens design. No UST projectors have a FRONT lens, which is what you would need to do what you want. They use a mirror system and a lens on the back to maximize distance between the lens and the screen without creating additional projector depth. This means the image has to clear the projector, which means it projects upwards slightly. So, it is going to be pretty standard to see 6"+ of offset from any UST projector, plus the height of the projector, plus the mount.

Please understand, you are in a VERY small minority of desired setups. Most people prefer more offset and most people have higher ceilings to work with. So, you are a 1% of a 1% type of setup. Which means you don't have odds in your favor for setup.

There also is a huge gap in availability between short throw and ultra short throw. There simply isn't anything in the .3 or .4 throw distance category. Not that there isn't ANY market for it, but the market isn't that large, and people STILL want a bit of offset typically.

Another factor is the 4K requirement as 4K support is still completely unnecessary in the commercial market by most users. The resolution is too high to make text readable from a normal viewing distance at normal screen sizes, so it is pointless to add that expense to most projectors.

So, you are left with a list like this...
https://www.projectorcentral.com/projectors.cfm?g=1&hide=0&st=1&exp1=1&r=1017&br=3500&br=12000&c=&w=&db=&ar=&zr=&wt=<g=&ll=&wr=&dt=&mfg=&p=&t=&pjl=0&pjw=0&pjh=0&exp4=1&td=&is=&i=d&tr=.2&tr2=.5&exp5=1&oop=2&sort=pop&sz=15#list

Which frankly isn't much of a list.

I think I would shoot for a model like this one and accept that a .48:1 throw distance is as short as you will get while maintaining a lens at the ceiling.

https://www.projectorcentral.com/Epson-Pro_L1490U.htm

In reality, I would reach out to both Epson and Panasonic to see what they have to say on this matter. They may have a short front zoom lens with offset which works for your desired setup. The .35:1 lenses all require the projector to be located in the center of the screen (top to bottom), so that is useless for you. But, models like the ELPU03S lens should work.
https://www.projectorcentral.com/Epson-ELPLU03S-lens.htm?part=10991

Epson can confirm better than I can, and I know Panasonic has an engineering division which can help customers determine a make/model which suits their needs.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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Thank you so much for your detailed response. Yes I agree, this is an edge case. :-) And a front lens makes more sense, which is why I was also considering the Dukane 68100.

The Epson Pro L1490U plus ELPU03S lens combo you suggested - as far as I can see from the PC calculator it would have a 23" vertical offset (at a 35" throw, with lens wide) - but its lens shift is only 11". (Or at 16:9, 21" offset with 9" shift, same height difference.)

This would leave a 12" difference to lower the lens center to avoid the image bleeding onto the ceiling. The projector is 8.3" high so figure about half or 4" from feet to lens center, that would mean hanging it around 8" from the ceiling.

Given the low ceiling height, I'm concerned having the lens be 12" below the ceiling would significantly increase the viewer occlusion. I.e. limit how close someone can stand to the image before casting a shadow. I'll have to diagram it to see how much of a problem this would be...

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Epson throw calc

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As I said, I would reach out to Epson or Panasonic and they should be able to direct you as to a best solution to what may work for you. If those guys don't have a usable solution, I'm really not sure who will.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.