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Discussion Starter · #1 ·
Hey there!!!


Well, the village idiot has yet more Questions for the AVS Elite (and non-elite http://www.avsforum.com/ubb/smile.gif )


I have finally come to the choice of a JVC G15, HTPC, iScan (for my older video game systems), and eventually an ISCO II Lens....


Now here are the dreaded questions?


1. How does the ISCO II work?? Do you set the mode to 4:3 and then let the lens work the rest?? What if the DVD was letterboxed??? I am really confused despite my constant studies as to how the different aspect ratios of DVD's fill the screen...


2. Can anyone give me an example pic of how the different aspect ratios look with the G15 (Milori???) If my screen is 145" diag.(4:3), how will dvds look in that mode???


3. When I switch the G15 to 16:9 mode, will the dvds be extremely squeezed??? What DVD format (i.e. anamorphic, 1.85.1, 2.35.1 would fill the 16:9 image of the G15?


I really would like Milori or someone else to describe to me the differences between the aspect ratios of DVD in realtion to what you will actually get on the screen...


And will getting the ISCO II make all DVD's full widescreen??


I just wish there was somewhere near to memphis I could drive and see one of these in action... I'd be willing to drive quite a ways to see a G15,.... or something better http://www.avsforum.com/ubb/smile.gif


Thanks guys for listening to the mumbling of the dumb!!!


KING RYGAR


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The basic idea with the anamorphic lens is to have all the devices in your system think you have a 16:9 display device. That means to tell your DVD player, your HDTV receiver, your scaler etc. that your output device is 16:9. This is especially important for the DVD player, otherwise it will downconvert anamorphic DVD's.


Now you have exactly the same issues that a user of a 16:9 display device has:
  • anamorphic sources -- show "as is" -- they are "tall and thin" but the lens will compensate
  • letterbox sources -- need to vertically stretch so it "looks" anamorphic. You can do this with the scaler, or possibly with the projector (I'm not that familiar with the D-ILA)
  • 4:3 sources -- assuming you have a 16:9 screen, you probably want to put the 4:3 image in the center of the 16:9 output. Again the scaler can do this. Alternatively of course you could remove the lens and zoom out, but that isn't very convenient.
 

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Discussion Starter · #3 ·
So with the ISCO II should I set my screen up for 2:35.1, and stretch DVD's of other ratios to fit it within Dilard or the Projector?? What does "Anamorphic" DVD mean??? Does that mean it will automatically adjust itself to fill the screen...


Ahhh, confusion... Good ol' friend of mine.. http://www.avsforum.com/ubb/smile.gif


King Rygar
 

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Rygar,


Anamorphic DVD's are mastered at 16:9. For movies with higher aspect ratios like 2.35:1, the images saved on the DVD will still have black letterbox bands above and below the movie.


So what Jim says is true: just assume that your G15 + ISCO II will act exactly like a 16:9 projector. For 2.35:1 movies, there will be black (sort-of :) bands above and below the picture.


Now for 4:3 images, again Jim is correct that you can either tell the projector squeeze the image to the center 4:3 section, or you can just remove the lens. I don't know how much the ISCO II lens changes the throw distance. And since it stretches the horizontal dimension, by removing it you should be left with a 4:3 image centered on your 16:9 screen. I don't think you'll have to rezoom that much.


[This message has been edited by mcg1969 (edited 10-06-2001).]
 

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Discussion Starter · #5 ·

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King Rygar,


I use a Dukane 9015 D-ILA display device, which in essence is the same thing as a JVC G-15 (if it has a zoom lens, then that is the one). These are 4:3 ratioed projectors.


I also have an Isco I lens, which I use to "squeeze" anomorphically enhanced images from DVDs so encoded.

If a DVD only has letterboxed widescreen images then I remove the Isco from the 9015's path so no distortions are seen...if I choose to do so; I can also use a Crystal Image video scaler, which has means to squeeze and unsqueeze enhanced DVDs, to allow the anomorphic feature to function. In other words, if I see tall and skinny images on the screen (because the DVD player is outputting a 16x9 image), then I use the Isco I lens to provide the squeezing and thus gain all the pixel resolution available from the D-ILA unit, thus effectively bypassing the scaler's own anomorphic mode. The scaler is set to output 4:3 ratioed imaging.


Oh, by the way...zooming of the D-ILA's lens must be left at its minimum setting when using outboard lenses.

Also, the differences between the Isco I and Isco II is the expansion ratio factor; the Isco I horizontally (the height remains constant regardless of the screen's aspect ratio) expand images by about 8% too much (1:44:1, I think), while the Isco II does it more accurately (is closer to the 1:33:1 ratio), albeit at a much higher price.

The mounting of these devices require careful positioning in order to avoid problems such as vigneting (darkening of the lateral areas of the picture), as well as adjustment of focus and correct horizontal positioning of the image within the screen.

Yes...I know...a bit confusing, eh? But trust me...


Things become even more confusing with the use of newer, software-based HT-PCs, which normally do the anomorphic squeeze automatically. But there are a number of software programs, like Jim Ferguson's YxY program, that work in conjunction with a PC and which allow for a wide range of adjustments to precisely suit your requirements and needs. There are even more sophisticated programs, like Millori's DILARD program (at substantial cost), which does all sort of things, including the calibration of D-ILA projectors (highly recommended, by the way).


My recommendations to you are this: first decide which projector you are going to use (G-15, G-20, etc.); then decide if you are going to use a PC for DVD playback exclusively, or whether you want to use an scaler with which to do playback of DVD, games, and other video sources; then decide about the desired size and aspect ratio of a screen. After that, then you can worry about the addition of an anomorphic lens attachment (Isco or Panamorph) if you must have one.


And I would also suggest you read a bunch of threads and posts dealing with these subjects right here in this Forum. There is a treasure trove of information which is apt to get you up and running in no time at all! http://www.avsforum.com/ubb/smile.gif


Good luck on your quest...


-THTS


[This message has been edited by Frank J Manrique (edited 10-07-2001).]
 
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