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Discussion Starter · #1 ·
As a potential LT150 owner and a projector newbie, I am confused about:


1. How different aspect ratios affect the image size (diagonal, width, and height). Is any dimension fixed as the aspect ration changes?


2. The LT150 User Manual includes a Throw Distance chart that provides values for a 4:3 diagonal. How can I convert the values for a 16:9 diagonal?


3. I will be using the projector primarily for watching DVDs. Should I get a 16:9 or 4:3 screen? If I get a 16:9, will I have to move the projector (closer to the screen) to get a 4:3 image on the screen without any of the image being projected outside the screen.


I should also mention that I will only be connecting an RP91 DVD player (component) and will not be adding a scaler or lens (eg. panamorph).


Thanks.



[This message has been edited by GaryWW (edited 07-28-2001).]
 

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GaryWW ( and you too, Don )

although i don't have the projector yet, from what i understand, it's the equivilent of a typical 4:3 tv. which means that from any given distance it will throw an image in 4:3 ratio, with a widescreen movie utilizing black bars comensurate with its aspect. i don't fully understand native mode and cinema mode, but i doubt that it operates like my sony rptv with an anamorphic squeeze...that would just be too good to be true for the price. what is more likely is that when set to 16x9, the projector 'masks' off the area beyond, but doesn't give you any increased resolution.

my plan was to use it in constant height/ variable width viewing ( just like a theater would do). and to accomplish this i do plan to move the projector closer or farther from the screen.

i hope to build a track system to streamline this process, but will need to wait till i get it in my hands.

i would think that without using a scaler, any other projector setting to accommodate different ratios with out moving the projector would result in poorer resolution than you would achieve by just physically moving it.


if i'm wrong or mis guided i hope somebody will correct me.
 

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I had promised myself that I wouldn't make any more posts on this forum for awhile - so much for promises!


The LT150 does do an anamorphic squeeze in cinema mode! You should be using a good proscan DVD player set to 16:9 (the RP91 will do nicely). Use natural 1 gamma setting for animation and natural 2 for just about everything else. You might want to increase brightness a little for darker movies.


Your screen width will stay the same - only the height will change with the different aspect ratios. A black pull down blind will work well for a top "floating" masking system.


Any "white" screen should work well - the Da-lite Hipower gives the image more punch and that's why I like it. Instead of mounting the projector on a track why not have a large 4:3 screen that you can mask to different sizes? My post called "To Save a Thousand Words" on the digital projector site describes how to construct a "floating" masking system - simple, cheap and effective. The masking system also expunges the DLP halo so you kill two birds with one stone. In fact three birds, since it will enhance blacks and contrast.


Cheers,


Grant

 

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Grant-

i'm shocked! if this projector does do an 'anamorphic squeeze'...i don't understand why there is such a clamour for 16x9 chips in the new projectors. with a fixed cabinet tv set, i can understand that there is a bigger difference marketing a 16x9 vs. a traditional 4:3, but why with a fp where the screen size is dependant on the throw distance and is not fixed. i'm confused.

i know the sony lcd and the new sanyo both crow about being 'true' 16x9 projectors, but if this one can get the same ( or essentially the same) resolution on that material..

with my sony rptv, when i use the squeeze the lines that make up the (h or v) resolution are compressed so that the same # of lines now occupy a 16 x 9 area. is that what this projector does? if so, it would seem to be an even bigger value than i originally thought.



anyways, thanks for chiming in as you are THE man to ask about this projector.
 

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also,

i checked out pics of your floating mask system on someones site, but for the life of me i can't make heads or tails of it.

my plan is to have the screen really open up to acommodate widescreen movies (i.e pulling the curtains back to expand the scope of the picture). while i may not go all out with a 2:35 screen, i do want to get the impression that the widescreen movie is more spectacular than the average 4:3...although i don't think i want to make the 4:3 as small as constant height would require...we'll see when the projector comes and i have a chance to play with it.

most likely i will use a constant height for 2:35-1:78 movies and then open up the top and bottom a little for 1:66 and 1:33. thats the plan anyway.

i realize the track would also have to acommodate a change in height as well as distance but i don't anticipate this being a great problem.

and yes, as a rptv tweaker, i have definately seen (or not) the light in regards to mask making. i got pilloried on another forum when i posted of my conversion (sounds like a silly, anal idea, but doggone it it works!).

some type of masking system is definately on the horizon.
 

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Discussion Starter · #7 ·
Grant,


Please confirm my (limited) understanding (and my mathematical abilities) of what you are saying about the screen/image size. If my "theater" will allow for a 100" diagonal 4:3 (80"x60") screen then I should expect to project an 80"x45" (92" diagonal) 16:9 image. Am I correct? And this is still the case when switching between Cinema and natural modes?


And because the width doesn't change and the throw distance is dependant upon the screen width, the projector will not have to be moved.


[This message has been edited by GaryWW (edited 08-01-2001).]
 

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The anamorphic squeeze done by a $:3 projector is not the same as using a 16:9 projector like the Sony. The squeeze will give you improved resolution, but cannot use all the resolution - you will get a very, very good picture. This is true for all 4:3 projectors - Seleco, Dwin, Marantz etc. The Panamorph lens basically turns a 4:3 projector into a 16:9 projector and all the resolution of an anamorphic DVD is used. I have compared a 4:3 DLP aganst a 16:9 LCD and I preferred the DLP - so don't worry about it the slight lose in resolution!


Gary, you're right - the projector won't have to be moved. To get the most out of this and any other projector construct a "floating" masking system. I put instructions on a post call, "To Save a Thousand Words" a few weeks ago. Look it up on the digital projector site.


Remember with this projector - uncheck the "white segment", try the different gamma settings, use a hipower screen and mask the screen, and use a good proscan DVD player, scaler or HTPC.


Cheers,


Grant
 
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