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Mark


You posted this about a month ago in response to Shawn posting about the coming 2.35:1 lens:


"I think that this is a great idea.

There would be a little more pre-processing required than with the 16:9 Panamorph, but it seems that all of the great, truly theatrical movies are 2.35:1.


The preprocessing could be performed by either an HTPC, the Rock or pre-stretching in the projector itself (like D-ILA).


Having said that, I think that a price over $2K is getting quite steep. That is more than it costs for some of the entry-level projectors!"


What about the prestretching within the projector? This would go a long way to resolving some of my (and others) installation issues if you came up with a simple proto command for this function.


Thanks Rick




[This message has been edited by rick e (edited 06-21-2001).]
 

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Hi Rick,


I'm still waiting to see how this works with the Panamorph 1! The question is not really whether it can be done (it can!), but how good is the quality of the picture after the digital pre-stretch and optical compress operations.


Here is a photo that I took of an example 'prototype' pre-stretch (without the optical compress necessary to make it right again):

http://www.dilard.com/images/htpix/panstretch.jpg


The same idea will work for the Panamorph II, but will require a higher "vertical scaling" setting, and will possibly need a touch-up on the "top" or "horizontal start" settings to position the image correctly.

EXAMPLE SETUPs>

For an example from the future, let's say that it's "kid's night" in your theater room. You are doing an animation double-feature..."The Emperor's New Groove" (16:9) followed by "A Bug's Life (Collector's Edition) (2.35:1).


You push a button and put the Panamorph I lens in place for "The Emperor's New Groove" (16:9 format). The button you pressed selects the correct pre-stretch memory on the projector for the 16:9 Panamorph.


After the movie ends, you take a pee break, and during the break, you push a second button and slide the 'rail' with the Panamorph II on it into place. Again, the "button" selects the magic 2.35:1 pre-stretch memory on the projector.


You then start up "A Bug's Life" (2.35:1) and everything matches up nicely (due to your previous set-up work).


The kids have a blast!


HOW DOES THIS WORK?s>

Well, it will always take a button push and a slide to get the combination right. The projector memories are inherently digital, and the Panamorph is completely analog. You might come up with a sophisticated electronic slide, but this is beyond the scope of this post!


One button, one slide. Always.


You will also need to know the source material to know which button/which slide to use.


Of course, this assumes an external scaler or similarly "simple" system. Introducing an HTPC will expand the possibilities (and the complexity) of a dual Panamorph system.


WILL THIS ACTUALLY WORK?s>


The projector has a vertical scaling range up to 800%, so we will not reach the limit of the range scaling 2.35:1 up to 4:3. There are only certain "valid" values, however, and I'm not sure if the exact ratio is one of them. There may or may not be a small amount of overscan when using the projector to do the pre-stretch.


I hope that helps!




[This message has been edited by milori (edited 06-21-2001).]
 

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Although this is very OT as you have summed up quite nicely I will voice the only fear I have over optical compression methods...


As I have many times said I am a HTPC fan... With this in mind I will be YxY'ing and using the Pannie (I) for full panel anamorphic and stretched LBX etc... To do this I will need to have 'keep aspect ratio' turned off...


My initial look at this (and please remember I am not so dedicated as to spend too long looking at stretched images without the damn lens !!) gave me problems with DVD menus defaulting to 4:3 full panel and films being correctly stretched...


I am very happy that having a fixed 16x9 window (plus blanking) and 'keep aspect ratio' means that 4:3 gets centered without any other user intervention... I know for many the only priority is the actual movie presentation but I am anally retentive enough that I want to have the 'auto switch' ability that my current system offers...


So any ideas how I can define the stretch for feature and stretch but pillarbox for menu's ??? This must not incorporate the PJ's scaler (mine can't handle it and maintain quality) but be a PC related function ???


Sorry to throw the cat among the pigeons http://www.avsforum.com/ubb/biggrin.gif !!




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Hey Phreddy,


No apology needed. I plan on exploring the YXY solution myself (being an HTPC kind of guy).


I think that most of us will agree that it's all about:[*] Ease of use[*] Picture Quality


I hope we can find a solution that maximizes both!


I have a feeling that there will be more than a fair amount of experimentation going on once the Panamorph ships!
 

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Mark, I am glad there are people with your level of skill on here to work through these niggles / config headaches... I would not be able to attempt much of what I do without these forums and would definitely have a poorer HT if at all.. I think you need to reverse the bullet points though ease of use over PQ in very un-HTPC http://www.avsforum.com/ubb/tongue.gif


I should point out that even if I have to set this as described above it would still only be as much of a 'cludge' as a normal 16x9 TV viewer has to live with (compressed 4:3), but I like my setup to perform flawlessly...


I also should say that my current YxY solution is not as flawless as I made it out above.. I have one situation that does not work perfectly and that is menu's on a LBX 4:3 title.. As I use YxY to zoom the LBX to fullscreen 16x9 when this setting is applied I loose (crop) most of the 4:3 menu.. To solve this I tell YxY that my 4:3 LBX titles (I only have two) are widescreen anamorphic.. This way when they start I get pillarboxed 4:3 and when the main feature starts I tell YxY (via pronto / girder) to switch to LBX stretch setup... Its not perfect as it does require one non automatic aspect ratio change but this is the only one in my whole setup not handled.. Hell, it doesn't have to mix my drinks in the evening and cook my breakfast afterwards http://www.avsforum.com/ubb/biggrin.gif


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