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Discussion Starter · #1 ·
Are the major 'real world' advantages of a PJ with a DVI input.


1) DVI ability to play movies that Hollywood encrypts with a protection scheme


2) 1 less a/d conversion with a PJ with DVI input.


My thoughts are that #1 (above) will never come to be (at least for a long, long time).


Regarding #2, has any one A/B compared the DVI and analog inputs on the PJ. Not so much test patterns but video, film etc. How significant is this step in the real world vs. a calibrated G15. With DILA technology, the signal that is carried to the DILA panels is converted to analog just prior to transmission (unlike DLP - all digital path). Thus, a DVI input on the PJ eliminates 1 A/D conversion relative to the analog input on the PJ.


How significant could this possibly be in the real world.


My reading is that DVI can only be used for playback and not for recording any signals.


I don't understand why DVI is so high on the list of priorities. JVC doesn't supply this output on its D-VHS. They supply (in addition to the analog outputs) firewire only. Why the conflicting digital inputs / outputs with arguably too very important, interconnected components.


Anyone have a clue? I certainly in the dark!


I'd like Tom Stites' input on this!


JEff
 

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Hey now, I thought you decided to go with the G15 and be done with it! You still nervous that you might be missing out on something big? :)


Seriously, I might refer you to this thread:
http://www.avsforum.com/avs-vb/showt...hreadid=123908

Interesting, you seem to have read this thread, since you posted to it. But if you want an example of an A/B test, there it is. Not only that, it's an A/B test against a heavily upgraded analog chain.


My honest opinion is that you will be happy with your choice of projector whether it's G15 or G150. Just get one and start watching movies...
 

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Discussion Starter · #3 ·
Mike,


Actually, you are partly right.


I really am curious to know if there is a big difference in pix quality betwen this DVI input and the analog.


Too many decisions, too little time.


Jeff
 

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Just for the record- its 2 less a/d conversions with a digital input. reason is:


scaler, pc, or other source -> (1) d/a step -> digital pj -> (2) a/d step


vs


source -> digital pj


I think youve got a good outlook on this because often things like this get you that last ounce of performance that makes a bigger difference on things like test material but not for every day life. I cant say if in this case it is true or not. But I suspect the impact of digital connections will be to bridge the performance gap between more expensive players that have better d-a steps and the less expensive ones because players will become transports. in today's world though, from people I know who have seen this, they all say the difference is worth the effort to go all digital. but if not, the results can be very good.
 

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Jeff


How does an unnecessary a/d - d/a stage affect audio quality? Video is no different. There is an inherent loss when you add stages of conversion. The simplest path is always the best. John Johnson found the benefits of DVI in his review of the piano.

http://www.hometheaterhifi.com/volum...02-part-2.html


Will you still get an excellent picture sans DVI with the G15? Hell yes. The Faroudja demo more than convinced me of that but DVI is just another step on the road towards video excellence.


Chris
 

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I know you're really looking for quality comparisons, but I think one thing that DVI has to offer is simplicity. Once both sources and displays have a DVI connection, we can throw away all the RGB -> YPrBr -> RGBHV transcoders and just hook them up with a standard cable.


Not that anyone in this group cares about simplicity;)
 

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Another benefit to DVI-D is that there are no timing issues to deal with to get "pixel perfect" 1:1 mapped display (well, assuming the projector allows you to address the full panel via DVI; some don't). You can throw away powerstrip, etc. I hooked up my Boxlite 300t to my HTPC w/DVI-D out and I had a pixel perfect, 1:1 mapped, gorgeous display five minutes after I took it out of the box. Zero tweaking required :)


-James
 

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James, unfortunately you can't throw away Powerstrip just because you get DVI. You still need a way to create the pixel-perfect resolution in the first place! And most video cards don't provide 1280x720 or 1365x1024 native. XGA projectors, though, are golden in this respect.
 

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Yes, I agree that you do need to be able to create the desired panel resolution. I was speaking mainly to the pixel alignment that often needs to be done to get pixel perfection. That's obviously not required with DVI. DVI display devices and sources define what resolutions they support in their EDID data structures. On the projector side, this is typically a very limited set (basic VGA, native rate (although some projectors don't even support their native rate - like the Hitachi 5500), and maybe a couple of others that can be scaled). Powerstip obviously can't do anything about that. I took a quick glance at the Powerstrip web page, and it didn't even mention any ability to modify DVI/TMDS data structures [EDIT: I'm referring to the graphics card here, not the projector, of course]. Can it actually do that? If so, that's very cool, and would be useful if your card for some reason doesn't support the necessary resolution. However, based on the spirit of the DVI spec, it appears that most DVI sources would be built to support any resolution, as long as it fits within the DVI bandwidth limit (as appropriate depending on whether the card supports a single or dual TMDS link). It would be interesting to hook up my Radeon w/DVI to a DVI device that has "non-standard" resolutions in it's EDID data structure, to see if it would support it.


-James



Quote:
Originally posted by mcg1969
James, unfortunately you can't throw away Powerstrip just because you get DVI. You still need a way to create the pixel-perfect resolution in the first place! And most video cards don't provide 1280x720 or 1365x1024 native. XGA projectors, though, are golden in this respect.
 

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Did KBK ever answer what PJ he was using? The dead lawyers thing was to encrypted for pre-coffee thought.


MRW
 
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