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Discussion Starter · #1 ·
I'm kind of baffled by the incredible rise in the picture of the HT1000. It's a 4:3 projector, which is supposed to be largely for home theater, but the rise in the picture rules out it's use on most any typical 4:3 screen installation in a home. Assuming an 8' ceiling and a halfway decent screen size (say, 80" wide) there's no way to position the projector (ceiling mounted) without the bottom of the screen sitting right on the floor. Go much bigger, and there's no way to even fit the screen in the room...WITHOUT using tilt and the digital keystone. It's almost as if NEC assumes every home theater will just use this 4:3 projector exclusively on a 16:9 screen. Seems a little odd.


Anyway, I know this has been discussed elsewhere but I was wondering how good a digitally keystoned picture looks on the HT1000. On other projectors I know that the use of digital keystone gives you those pixel step/pivot points which are horribly distracting and they usually generate other artifacts to boot. How good is the digital keystone of the HT1000?


I wish it had either optical keystone or lens shift...or just a reasonable rise in the picture, then I'd be all over getting one!


Thanks in advance for any responses
 

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IN a room with a 8' ceiling, I am projecting a 96" image from 12'. I have the 4:3 image about 12" from the top of the wall. There is keystone, with the bottom of the image just slightly narrower than the top. But to be honest, it is not a distraction for me. To get a perfectly verticle left and right side, I would indeed need to drop the image down to the floor, but I am living with the image with the very moderate keystone.


I am planning to try an anamorphic lens, so the whole keystone issue may become moot.


I tried the 3D Reform and I did not notice any negative artifacts in the signal presentation. The only distraction is the odd angle blanking that is barely visable. Formatting the image to a screen that masks the area outside of the "reformed" image would be a good way eliminate the odd blanking.


However, I have not been distracted by the mild keystone of aiming the screen image a little higher than a perfect alignment.


RJ

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Discussion Starter · #3 ·
That's encouraging to hear. Thanks.


Why exactly would the anamorphic lens make keystoning moot?
 

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RJ, let me know how the anamorphic lens works out, as I'm interested in this also!!!


Scott


PS. Alan told me an Isco would not work, as the apeture is too small, or something like that, but he said it definatly would not work.


Me again!!
 

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I think the ISCO II would work great with the HT1000.


-Mr. Wigggles
 

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I am using a moderate amount of keystone correction (about half of what the HT-1000 can do), and if there are any artifacts, I can't see them. Perhaps if I stared at a test pattern I could, but on normal non-HD and HD programming - using DVI, Component, and S-Video inputs, I just can't see any distortion.


I have tilted the top of the screen out (mine is a fixed wall amount) to reduce the amount of correction needed.
 

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My Sharp DW100U's digital keystoning is totally unwatchable when viewing high-motion things such as sports. I tried various settings from nearly full to nearly none, and it almost looks as if the screen is wrinkled!


hjones, you're saying that you have a different experience with your ht1000?
 

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Quote:
Originally posted by scottyb
RJ, let me know how the anamorphic lens works out, as I'm interested in this also!!!
I'm not sure which lens will be the best solution for the HT1000. It seems the throw is a little short for use with the Panamorph which likes to see a 1.85 minimum.


Prismasonic has (2) lenses that should be available in the beginning of January. One the stretches the horizontal and the compress the verticle. I have asked for throw ratio requirements for both lenses, but no feedback yet.


I'll keep the forum posted as I learn any additional info.


RJ

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Re HT1000 + ISCO, Alan said the short throw, and I presume the high offset, give bad pincushion (or is it barrel?) distortion.


Does anyone know if this would work: Tilt and offset the ISCO so that the beam bundle is as centered and symmetrical as possible as it passes through. Correct any keystone induced by tilting the pj/ISCo as a unit.


If I understand correctly, the beam on offset leneses is actually using only the top (for floor mount) or bottom (ceiling mount) of the lens.


Thanks
 

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Quote:
Originally posted by noah katz
Re HT1000 + ISCO, Alan said the short throw, and I presume the high offset, give bad pincushion (or is it barrel?) distortion.


Does anyone know if this would work: Tilt and offset the ISCO so that the beam bundle is as centered and symmetrical as possible as it passes through. Correct any keystone induced by tilting the pj/ISCo as a unit.


If I understand correctly, the beam on offset leneses is actually using only the top (for floor mount) or bottom (ceiling mount) of the lens.


Thanks
I thought Alan was speaking of the Panamorph lens on the HT1000. The Panamorph likes to see atleast a 1.65 minimum throw ratio, and I calculate the HT1000 zooms from a 1.27 - 1.52 ratio.


The HT1000 does offset the image in the lens as you noted. It's oriented to the top of the lens. For a ceiling mount, you invert the the projector and a set up change in the software to "front ceiling" which inverts the signal on the chip. But the image is still focused at the top of the lens assembly.


Perhaps there is an adjustment to lower the image output in the lens, but then again the cat eye iris is also oriented to the top of the lens assembly.


RJ

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blw: Alan said he did not see distortion with the keystone correction on the HT-1000 except with the DVI input and even then it was not noticeable on normal program material. I don't notice anything on any of the inputs, although I don't watch test patterns. I do intend to snug the projector closer to the ceiling when my new ceiling mount comes in today - I have been using a modified mount from my old PJ until NEC started shipping their mounts.
 

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For a ceiling mount, you invert the the projector and a set up change in the software to "front ceiling" which inverts the signal on the chip. But the image is still focused at the top of the lens assembly.


RJM321,

Can you clarify for me. This then forces the screen "down" if you will, versus having the projector on the ground - which forces the image up. Correct?

Thanks.
 

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Quote:
RJM321, Can you clarify for me. This then forces the screen "down" if you will, versus having the projector on the ground - which forces the image up. Correct?

Thanks. [/b]
The HT1000 presents the image above the "top" of the projector in both desktop and ceiling projection modes. The ceiling projection mode simply flips the image to compensate for the projector being upside down. The alignment of the image coming out of the projector is the same for both ceiling and desktop.


RJ

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Discussion Starter · #14 ·
Any more thoughts from anyone about how usable (picture quality-wise) the digital keystone is on the HT1000?
 

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Quote:
Originally posted by PRH
Any more thoughts from anyone about how usable (picture quality-wise) the digital keystone is on the HT1000?
The 3D Reform and Keystone adjustments on the HT1000 work very good and I have yet to see and artifacts when they are used.


The only thing I notice is the slightly visable projected "black" of the area masked with keystone correction.


RJ

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