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Discussion Starter · #1 ·
After a lot of research, I've concluded the best overall viewing situation with the Boxlight 38T/Sanyo XP21N projector I'm going to install is to have the default setup as 16:9. Here's what I want to do--tell me what I need to have to get there--Quadscan (preferred) or HTPC?


Combine the 38T with a Panamorph (I already own one) and 110" 16:9 Grayhawk. I'll set it up so the projector is outputting the 16:9 image in 4:3, which will then be resqueezed by the Panamorph to 16:9.


For 4:3 viewing, I would like the image to be centered horizontally on the screen so it would be 90" diagonal (54" x 72"). Everything I've read indicates the viewing experience is much better if one doesn't try to have a too large NTSC picture, because even with scaling, the resolution and quality is pretty marginal.


This means (I think), I'll have to take the native 4:3 image and squeeze it even further if I want it to come out right after passing through the Panamorph.


The first thought comes to mind--move the Panamorph for 4:3 viewing. Here's the problem--with this screen, the image would be 72" high, not the 54" of the screen. So I'd have to shrink it to 54" high in order to fit the screen. The projector placement is such that I cannot zoom it down to this size, so I'd have to shrink it via scaling.


Ok, scaliing experts, how do I get there from here??


Dan


[This message has been edited by DanHouck (edited 07-30-2001).]
 

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Ok, Dan. It sounds like you have an XGA projector with a 4:3 display panel. I don't own a Quadscan so I can't help you out there. I doubt that they have a 16:9 to 4:3 option, though. In any case, what you want to do, is squeeze the 4:3 image in the horizontal plane by 25% or multiply your horizontal resolution by 0.75 and bingo, that's what you will use. So you will view 4:3 material within a 768 by 768 window. Now, here's the catch. This will only work with DVD's and YXY. If you can get software like DScaler for cable/satellite NTSC and manipulate the image with YXY, then great. I watch very, very, little TV. So I am not up to speed on the latest regarding watching TV through PC's. But irregardless, you must have the ability to scale your NTSC input. Without that, it's a no go. I was able to get dTV (pre-cursor to DScaler) to work with YXY, so I don't expect any problems. If you want to scale DVD's only, then this is as easy as pie. But TV stuff will be more involved. If you are comfortable with PC's, this will probably be a piece of cake.


Now here's my tip on how to get this to actually work. Forget about typing 768x768 in your YXY setup window. The pixel values are inaccurate. You have to get out your tape measure and set the values in YXY after you have obtained the correct geometry. This is easy. You just keep shrinking the window horizontally, until it is at it's proper width (there is a button you can "click" that will shrink the window, or you can just enter a value and go from there).


You have two choices in how to do this.


1) Get out the Avia disc and select the letterboxed circle hatch pattern. Make sure the circle is shrunk until its width matches its height (WITH the Panamorph in Place). Bingo you're done.


Or,


2) Take the height of your compressed 4:3 image and multiply it by 1.33. The product is the width that you should obtain by narrowing the image horizontally, with the Panamorph in place.


Both steps require a tape measure. Calculating the pixel values are good for theoretical values only, if you are using YXY.
 

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Discussion Starter · #3 ·
So Larry, what you're saying is I can only do this with an HTPC?


Dan
 

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No, I'm saying it can be done with an HTPC. I don't own any external scaler (besides my dedicated HTPC), so I can't give you advice in this area. Sometimes getting people to answer a simple question can be like pulling teeth. Hopefully someone will step forward and tell you if there are any external scalers that will horizontally compress the image by 0.75x. Off hand, I can't say I know of any scalers that do it.
 

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Discussion Starter · #6 ·
John, could you elaborate?? Which CI?


Dan
 

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The iScan Pro will do this. It has a reverse squeeze switch that will center a 4x3 image within your 16x9 screen. You can leave the Panamorph in place, and never move it. It will work with all your DVD or NTSC sources.




[This message has been edited by drmyeyes (edited 07-30-2001).]
 

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Hi Doc,

I think this is different. To keep the Panamorph in place (and not ever move it), you need to scale the video from 1.33:1 to 1:1. To view 4:3 material within a 4:3 "window" within a 16:9 display is something else. Humbly submitted.
 

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Dan,

John is referring to the Crystal Image (CI) scaler from AV Science. The CI does a few scaling tricks that the quadscan doesn't. Even if neither scaler does it right now, there's no reason why a software update couldn't support it - unless there isn't room for more settings.
 

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Discussion Starter · #10 ·
OK, so if I understand it right, the CI could like take the 4:3 image and squeeze it to 3:3. So the vertical dimension (the second 3) is unchanged, hence the picture will still fill the entire 54" of the 16:9 screen, but the Panamorph will restore the first "3" to 4 and I'll end up with an image that fills the screen vertically and uses 72" of the 96" width, with "black bars" on the left and right.


But I thought I read somewhere the CI is not the best for digital projectors??


Dan


P.S. I'm chewing on this because the SU (Spousal Unit) made a very firm statement about how she just wants to watch movies on the big screen and she wants this thing to not be so complicated she can't run it. I have my marching order, guys!
 

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Hi Dan,

Here's how it would work (assuming the CI has this option):

The CI converts the 4:3 image to 3:3, by dropping horizontal resolution (squeezing the image horizontally). The Panamorph takes the latter "3" in 3:3 and compresses that vertically to 2.25. 3/2.25 = 1.33:1 aka 4:3.
 

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Hi, Guys-


The iScan does do this (unless I'm misunderstanding what you want to do.) I'm using it. I've got an ISCO II, which I'm using with a VT540 and iScan Pro. With the lens in place, I've got a 16x9 image, flipping the switch on the iScan provides a properly centered, 4x3, properly proportioned, non cropped, image by horizontally squeezing the image, negating the stretch of the ISCO (or squeeze of the Panamorph). I haven't figured out the numbers (I'm sure Larry is right), but whatever, it works.


The only caveat about the iScan is that for other than this feature, it is not really a scaler. The ultimate image quality will depend on the quality of the scaler in your projector. With the VT540 it looks great, don't know about the Sanyo.


So... it works for 4x3 in the middle of 16x9 without removing your lens. Or did I misunderstand what you wanted to do?
 

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Discussion Starter · #13 ·
Nope, you've got it right but the Isco works different than the Panny so I'm not sure it would still work. The Isco as I understand it actually shrinks the image vertically where the Panny does it Horizontally. That's why the Isco changes the throw distance and the Panny doesn't.


I think I may end up with an HTPC. By the time I buy a good scaler and DVD player, it's almost the same cost as AVS's top of the line HTPC. I just have to convince myself that I can operate the damn thing.


Dan
 

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Discussion Starter · #14 ·
Tom:


I already own a Panamorph and the PLV has a number of issues with its internal scaler. Plus (main reason) it is less than one-half as bright as the XP21N and I need the extra brightness for the room I'm working with. And the PLV60 does not have MLA.


Larry:


I'm going to research the IScan. But it is not a scaler, correct? So it won't improve on the pretty weak internal scaler of the XP21N/38T.


Dan

 

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Dan,

The Iscan does the deinterlacing. So now, your projector just has to handle the scaling, instead of deinterlacing (interlaced to progressive) and scaling. The iScan would certainly be the cheapest option.


EDIT: That's right, Dan. The iScan is a line doubler, not a scaler.


[This message has been edited by Larry Davis (edited 07-31-2001).]
 

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But I thought the scalers in recent projectors are all pretty good, and it is the deinterlacers/line doublers/quadruplers that have the shortcomings. If this is correct, the projector can probably scale your 480p from your outboard Iscan just fine. Does anyone know?


------------------

Joe


Boxlight 38t

Panasonic RP91

RCA DTC-100

Da-Lite 100" 4:3 1.3gain

Studio Experience SE616's

and some other stuff.
 

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Discussion Starter · #17 ·
OK, Larry and Joe:


I see two possible relatively simple and cheap alternatives to my aspect ratio problem:


#1 Larry if I understand you correctly, I could use the IScan Pro in conjunction with a good interlaced DVD player and Digital cable box to solve the aspect ratio problem. When I'm watching DVDs, I could set the IScan to output the 16:9 image as 4:3 so the full 4:3 panel of the XP21 would be used and, post panamorph, I'd have a full screen 16:9 image.


The digital cable box would be input to the Iscan via an SVHS cable. The IScan would output the signal as 480 P and would also be able to do the necessary 3:3 squeeze so that, once again, the post-panamorph picture would be full height on the 16:9 screen and have black bars on the sides only?


This setup would rely on the scaler of the XP21N to scale up the 480 P to XGA. Joe, you seem to think the scaler is OK and based on your RP91 findings, you may be correct.


So all I'd need for now is a cheap IScan Pro and a better interlaced DVD player (I have an old Toshiba 2109), correct?


#2 If I use a CrystalImage, I would have the same ability to squeeze the output to work properly with the anamorphic lens but could also bypass the scaler in the projector.


One of these might be a decent interim solution until QuadScan comes out with their unit for anamorphic lenses (it's in the works according to them).


Make sense? Is the scaler in the CI any better than the one in the projector?


Dan



[This message has been edited by DanHouck (edited 07-31-2001).]
 

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Dan,


#1) I don't own the iScan Pro, just the original iScan. I can't confirm it does 1:1 scaling. To use the full panel of your display with anamorphic DVD's, you would take the S-Video out of your DVD player (maybe component?) into your iScan Pro and take the 480P RGB out put of that into your projector. You set the DVD player to output 16:9 and you're all set.


#2) I don't think you got a clear cut answer regarding a 0.75 horizontal compression on the CI.
 

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Dan, Larry- right, right.

I happen to own both an original iscan and the pro. The differences are the pro accepts component in, has color and picture controls, and does the above 'reverse squeeze' (a feature I was unaware of and pleasantly surprised by when I received it).

I admit that the above was a waste, I could have put together an HTPC for the price of the 2 iScans. Nevertheless, if you just buy one it will work and should be your cheapest alternative, as well as the easiest. Anyone want to buy my version 1?

You should also realize that when the iscan squeezes the signal, you are no longer really using the full 4x3 panel of the projector. Theoretically the resolution is less as you are using fewer pixels but for this material it doesn't seem to matter.


[This message has been edited by drmyeyes (edited 07-31-2001).]
 

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Hi Dan,

1)Question: Will the quadscan prequeeze images formatted in a 4:3 frame (standard and letterboxed) and output at computer resolutions (XGA included) to a 16:9 device.

Answer:

No, the quadscan is an able scaler that utilizes the same deinterlacing chip as the CI, but it does not provide the mechanism to electronically, horizontally pre-squeeze 1.33:1 material into a 1:1 frame so that 4:3 material can be displayed correctly after being optically expanded by the isco or panamorph. To be fair, the quadscan is able to output to 16:9 screens without a lens by vertically shifting the 16:9 image on the panel to 3 pre-determined, positions (fix to the top of the panel, fix to the middle of the panel, fix to the bottom of the panel). As long as you line the projector up correctly, the quadscan will allow you to 4:3 center a 16:9 image without the use of a lens. A nice scaler, that is a little long in the tooth, but still produces a good, but not the best picture available.


2)Can the CI center a 4:3 image on a 16:9 screen, while using an optical anamorphic adapter in a permanent?


Yes, but as explained above the genesis deinterlacing chip in the CI scaler is not state of the art. The image is good (better than unscaled), but it exhibits softness and combing artifacts not present on either the Geforce/Radeon based HTPC's.


The CI would be setup with an output resolution of 1024x768, screen aspect set to 16:9 (key step to producing this ability)- with the setting above the scaler is doing something strange considering there are no 1024x768 projectors that have a 16:9 AR. This electronic pre-manipulation of the image allows us to keep the lens in place while diplaying correct image geometry.

The AR source selection of the CI is controlled with discrete IR codes yielding:

1)4:3 material centered in the middle of a 16:9 screen (it unfortunately incorrectly displays 4:3 material in a 1.44:1 AR) (the output to your projector would be 768x768 pixels ideally, but probably is closer to 830*768)

2)16:9 enhanced material fill the full screen width when selecting "anamorphic", maintaining the correct AR and taking advantage of the increased vertical resolution of 16:9 enhanced disks (assuming you have set the DVD player to output to a 16:9 monitor and never changed it)

3)letterboxed material is displayed at full screen width (not in a 4:3 box in the center of a 16:9 screen) without geometric distortion when you select "letterboxed"


Long in the tooth, but still functional. I have installed both of these and the images are not as good as HTPCs, but better than most projectors internal scalers. I have not done A/B comparisons on this unit vs those projectors with built in deinterlacers with the inverse telecine function.


Both the quadscan and CI occupy a price point that the new class of scalers have not approached (easily under 2k).


The ISCAN's deinterlacing is superior to both of these scalers, but it does not scale to native resolution. I realize that most of the magic is in the deinterlacing, but it may be an issue with your projector. It does not allow IR control of the AR change, and most importantly, appears unable to perform a letterboxed zoom to fill the full width of your 16:9 screen with correct geometry.



As other have mentioned above the HTPC give you a boat load of flexibility to manipulate unlocked AR of the image, but it is not as turnkey as a scaler for those without technical ability. It can be made close to bullet-proof, but it has its issues.



The scalers at present that appear to have the capability you are looking for include:

1)The Rock-can make adjustments for all ARs with NTSC material. Price has gone up significantly since initial release. See Tommyboys review for picture quality details.

2)Vigatec-appears to be able to scale all NTSC and HDTV resolution to the native panel of your projector and pre-manipulate the image so that the ARs can be displayed without geometric distortion while keeping the lens in place.


To be determined:

1)The faroudja's NR product appears to have this capability from the manual I have read, but I have not seen comments on this ability to this date.Page 6 of the manual clearly state under the screen shape section that the "wide" setting should be used when the projector (in this case the lens with the projector) will provide the anamorphic squeeze and you are using a widescreen.

2)The Leeza-likely will have simliar support for the anamorphic lens as the Rock, but time will tell.


------------------

STOP HDCP on DVI

Don O


[This message has been edited by Don O'Brien (edited 08-01-2001).]


[This message has been edited by Don O'Brien (edited 08-01-2001).]
 
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