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I have been out of the loop for awhile. I got a D1 when i t came out, don't have any new firmware, but wanted to see if anyone now has a way to output it through DVI to my Grand Wega III with a 1:1 ratio?? Thanks!
 

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It may be a moot point - there's another current thread here that claims that the Sony converts to analoge internally and then back to digital for display.


Ed
 

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Regardless of whether or not any extra A/D to D/A conversions are done, feeding the GWIII (or any other digital display) native res will prevent any extra scaling to be done (the conversions have no effect on resolution). That being said, there are multiple model years and models of the GWIIIs, I don't believe all of them convert digital to analog and then back. If it is really important to the poster (or anybody else) I'd suggest going to the RPTV forum and look/ask for the real answer - and then I'd only believe a few certain people there. :) And, with all that being said, I don't recall people being very successful feeding native res to the GWIIIs. Again, asking in the RPTV may get better results.


larry
 

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Quote:
Originally Posted by PooperScooper
Regardless of whether or not any extra A/D to D/A conversions are done, feeding the GWIII (or any other digital display) native res will prevent any extra scaling to be done (the conversions have no effect on resolution).
If the input signal is converted to analog then there will never be any scaling regardless of the input resolution. The analog signal will merely be converted to the native resolution.


Ed
 

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Quote:
Originally Posted by ekb
If the input signal is converted to analog then there will never be any scaling regardless of the input resolution. The analog signal will merely be converted to the native resolution.


Ed
Huh, what are you trying to say. That is scaling isn't it?


The fact remains that the 788p Sony LCD GW series TVs will not accept their native resolution via HDMI or DVI. You can try to fool yourself into believing that you got 1:1 pixel mapping but you have not truly achieved it. The 788p GW series TVs will only accept 480i, 480p, 720p, or 1080i via their digital connections. Nothing Else! All of those signals will be converted to analog and then scaled to something like 1388x788 which is the TVs native display resolution. These particular TVs will always scale every signal that it can accept no matter what signal you think you are sending it! That being said, you probably wouldn’t be able to tell the difference if you could achieve 1:1 anyway. The Sony scaler’s and deinterlacers are some of the best. Their new A10 TV is a different story. It has a native 720p resolution. You could feed that TV 720p and have 1:1 pixel mapping.
 

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Quote:
Originally Posted by mpgxsvcd
That is scaling isn't it?
I don't think so. Scaling is a mathematical/algorithmic process that is applied to the digital signal to convert from one resolution to another. Once you convert it to analog and merely digitize to get the native resolution, you are not scaling.


Ed
 

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Quote:
Originally Posted by ekb
If the input signal is converted to analog then there will never be any scaling regardless of the input resolution. The analog signal will merely be converted to the native resolution.


Ed
How do you scale in the analog domain? _If_ the GWIII converts the DVI input to analog, the assumption is that it feeds this YPbPr signal to the same internal inputs that the component YPbPr input is routed. The analog YPbPr is converted to digital, scaled to native res and then displayed. All digital displays have to work this way when given an analog video signal. Ideally, digital DVI RGB video info is fed directly to the scaler and scaled to native res. Sometime the extra D/A or A/D conversions degrade PQ (may or may not be noticeable) - but don't change the video resolution.


larry
 

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Quote:
Originally Posted by PooperScooper
How do you scale in the analog domain?
You don't. Scaling is strictly a digital concept.
Quote:
The analog YPbPr is converted to digital, scaled to native res
No - when you convert from A->D, you digitize to the native resolution and therefore you do not need to scale from one digital resolution to the native resolution.


Ed
 

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Quote:
No - when you convert from A->D, you digitize to the native resolution and therefore you do not need to scale from one digital resolution to the native resolution.
Strictly speaking A->D is taking an analog frequency or voltage sampled at a point in time and and converting it to a digital value. I don't believe you can take a 480p YPbPr analog signal and convert it into 1280x720 YCbCr (or RGB) pixels in one step - and have it look right. :) (The 1280x720 is just an example resolution). It's so much easier to take a 480p YPbPr analog input, convert it to 720x480 YCbCr (I'm guessing the format) pixels of video info and then scale up to 1280x720. If you didn't do it in two steps, implementing different scaling algorithms would be a PITA.


Now, if the incoming analog signal is native res (like we were talking about previously), then no scaling would be done, just A->D. eg. A high def stb sending 720p over component to a 1280x720 native res DLP TV or PJ. The DLP display would just be doing A->D and no scaling. Maybe this second part of my post is the scenario you were speaking about.


larry
 

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larry,


I see your point now. I must admit that I don't know enough about the details of how the analog siginal is digitized. But what you say makes sense and may be what actually happens.


So it boils down to the fact that the analog signal in some sense is a hybrid signal - you have discrete scan lines ("digital" in the vertical direction) but continuous (analog) along scan lines (horizontally).


Ed
 
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