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The current Panamorph, model P751, is designed to serve two parameter spaces. To summarize from the web site, if the projector is not tilted, the Panamorph will form an image shifted down by approximately 0.048 times the throw distance and the compression factor will form an image aspect ratio of 1.71. If the projector is tilted up by 3.9 degrees, the image will move up so that the top edge of the 1.78 image is about where the 4:3 top edge was. There will also be a small amount of keystoning due to the projector tilt.


Another design has been prompted by some projector manufacturers who favor the accurate 1.78 ratio with no projector tilt and, preferably to them, with an additional image down-shift so that the 16:9 screens are closer to the eye-level of their customers. Coincidentally, this new parameter space allows more weight to correcting image aberrations during optimization since the image is not forced to a particular vertical position. The natural down-shift that this OEM design yields is approximately 0.08 times the throw distance (a 12†drop for each 12.5’ throw). Interestingly, this offset would be similar to that of the 2.35:1 conversion lens recently discussed, so the heights of the 16:9 and 2.35:1 images would be about the same.


This said, if any prebuy customers would rather have the OEM version over the original, please state so here or through email to me. This should be treated as a survey at this point. If there is significant interest we will take the steps to provide this option.


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Shawn Kelly

Cygnus Imaging www.cgns.com


[This message has been edited by Shawn Kelly (edited 06-15-2001).]


[This message has been edited by Shawn Kelly (edited 06-15-2001).]
 

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Original.


I have an 8' ceiling so the original version works better for me I would like a 235:1 that also did not shift down as much.


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Jim Nissen
 

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Shawn,


After reading your pros and cons - I think I would go

for the OEM version that provides the 0.75 compression

with no tilt.


Since I haven't mounted the projector yet - the degree

of downdrop is a free parameter - I can mount the projector

at whatever height it has to be.


Greg

 

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Shawn

I'd probably go with the new option, assuming it doesn't drastically change delivery times. Also the fact that the shift would be almost equal on the Pan 2, would make me more likely to purchase it.

I assume the settings on the Dwin DLP to change the image to accomadate the Pan. would not be affected

Michael


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tuckerdog
 

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Quote:
Since I haven't mounted the projector yet - the degree of downdrop is a free parameter - I can mount the projector at whatever height it has to be.


Not exactly. If you downdrop it too much, you will be knocking into it with your head. The downshift will be helpful in getting the image closer to desirable viewing height (if i understand this correctly).

 

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Shawn,


I think I would prefer the OEM version as well.


Thanks


Larry Vale
 

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Original for me.


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*********************

Kirk Ellis

G1000 D-ILA, HTPC, Panamorph (soon I hope),

Dish 6000 (HBOHD,SHOHD,CBS,NBC,ABC,WB,FOX,UPN, KCET -- does it get any better ?)
 

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This sure is an interesting ride. First off. Congratulations Shawn on the interest from the manufacturers and heres hoping it is a big success.

This new version has me asking questions that I thought I knew the answers to. A projector that is level ceiling mounted has a drop of .048 times the throw distance and ends up with a aspect ratio of 1.71. This is about 3.5" too narrow to fill a 16:9 screen with a 106" diameter. If I want the picture to fill the screen I have to leave the projector mounted where it is now and tilt it 3.? degrees and this will then give me the correct 1.75 ratio but there will be keystoneing. Am I right so far?

If I raise the projector up the 8" and keep the projector level will the picture still look slightly tall and skinny because of the 3.5" that is squished too much?

Will the new version give us a better picture?

What will happen to the people who have stated their ceilings are too short. e.g.. If someone can raise their projector almost the full height (2" or3"less than optimum) and then tilt the projector down to accommodate this 2" difference, would the aspect ratio change as much as it does for the 1st version and would the picture quality suffer?

I think what people would be afraid of is the reviews for one lens being substantially better than the other version.

It does seem to make sense to have the correct aspect ratio come out of the lens. If I am off base in any of this ramble please let me know because I can't decide which is the one I want. I had always thought that when we raised the lens the .048 we would be getting the correct ratio. It was probably posted 100 time but maybe I just didn't want to see it.

One last thing. Do you have any idea what type of delay we are talking?
 

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Shawn,

With my situation having an inverted projector on an 8ft ceiling, I better stick to the original version.


I am already pointing slightly upward to project a 16:9 desktop onto a 16:9 screen with my lens center at 2.5" higher than the top edge of the screen. Correct me if I'm wrong, but I am assuming the OEM version is more appropriate for those with higher ceiling mounts(?).


Carey


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My forever in-progress Home Theatre
 

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XrayEyes,


Actually - it works the other way.


I have decided the height of the screen and have ordered

it. I have not as yet mounted the projector - but I did

rig up some strings as to where limits of the projector's

beam were - to make sure it cleared with a good margin of

headroom.


If the downdrop is increased - it means that I have to

mount the projector even high - since my screen height

is fixed - and the angle will be steeper. The slope of

the top of the beam for an inverted projector is the

0.048 inches per foot of throw for the original version,

and Shawn reports the OEM version will have a slope of

0.08 inches per foot of throw - so it's steeper.


The bottom line is - with the new OEM version, I'll have

even MORE headroom - because the screen stays put and the

not yet mounted projector will go up higher.


Greg
 

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Hello Shawn,


Before I make a difinitive decision, I would like to talk to you or another expert so that I fully understand the differences...


But for the sake of this poll, I am leaning towards the one more similar to the PII (since I am purchasing both).


Thanks,

Paul
 

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For me this depends heavily on "allows more weight to correcting image aberrations during optimization" for me the original Pannie sounds best in my current setup...


As I am using only a SVGA PJ and wont be leaving permanent 16x9 in place (much source is OTA TV and pillarboxing via YxY will result in a net loss of rez and light both much needed in my non light controlled room with only SVGA).. I have a 1.78 screen and can overshoot by an inch or so above (onto border) and undershoot by an inch or so for a 1.85 DVD and all is well... I am assuming that the minimal downshift will also fit my situation very well but...


The Pannie is one device I intend to keep for a long time... I am interested in the maximum image quality possible (I believed this was the original design spec) and will later have a PJ that I can leave fully 16:9 and 'waste' space with 4:3.. In this setting quality is paramount...


So how much image quality difference is expected ???


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HTPC without using windows... GUI Front Ends for Home Theater
 
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