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Discussion Starter · #1 ·
Greetings. I was recently forced to abandon the Hitachi 5500 as a prospective FP for my living room, which I was considering in spite of the 99% likelihood that I would have to literally bounce the unit back to Hitachi upon receiving it, to hopefully fix the purple issue under warranty. The reason I had to abandon it was because of this little-known (well-hidden?) revelation: (Copied from the thread "Best Scaler for Hitachi 5500")


> - The 1365x1024 panel apparently cannot be mapped pixel by pixel. It is said that the internal scaler limits the resolution to 1280x720 or maybe 768.

> - It is also said that the Faroudja NRS for this unit, is configured for 1280x720.


This was later clarified:


> I spoke with the engineers at Hitachi about 1-1 pixel mapping over the whole panel, unfortunately this can not be fixed with an upgrade. basicly it syncs on the vfreq so it can not distinguish between 1280 x 1024 and 1365 x 1024. Unlike the JVC it does not have a eprom that you can writ new resolutions to.

> 1280 x 1024 is max for 1-1 mapping


I forwarded this information to my fellow researcher. In turn, he conducted a brief email conversation with a person at Faroudja. Here is a quote from said person:


> The correct output rate of the Faroudja NRS-Plus is 1360 x 1024. Since

> the Hitachi is receiving the signal in the analog domain from the

> Faroudja, there is no performance difference between 1360 x 1024 and

> 1365 x 1024.


So what we have here is end-users discovering certain facts about the limitations of the Hitachi 5500, and Faroudja indirectly denying those facts.


Would anyone be willing to judge how these two seemingly conflicting data could possibly coexist? My (vain) hope is that the Hitachi may in fact be somehow capable of accepting pixel-perfect video at 1365x1024, or at least the 1360x1024 which Faroudja quoted.


---


Moving right along, there is still the matter of the JVC G150CL and its ability to make a Xenon lamp last 2000 hours. I've been hoping somebody has taken the time to measure the ANSI lumens when this option is enabled. It has been said that the option reduces the lamp output to 70%, but at the same time it was also said that the difference was minimal (implying that the actual brightness alteration wasn't anywhere near as dramatic as a 30% loss).


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And while I'm at it, I may as well ask... Is it true that the DVI input on the G150CL is worthless because the panel's resolution (1365x1024) is higher than the maximum permitted by the DVI spec?


Thanks as always.
 

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Hi Colmino,


Short answers - No, the Hitachi can not directly pixel map the full panel. It can do that feat only up to the regular SXGA resolution (1280x1024). I have one, and have verified that. I have also been conversing with Hitachi engineers (indirectly, through "tycoondog") who confirmed it.


Faroudja might have meant that IF it were possible, the NRS should be set to a 1360x1024 resolution.


The G150CL will be able to do this, as it contains 3 separate memory locations for SXGA resolutions. SXGA3 is 1365x1024 (or 1360x1024, with 5 blank pixels, which is the way most people run them).


Perfectly pixel matched, 1:1 analog SXGA video (through the HD15 VGA connector) with properly set tracking and phase is very difficult to distinguish from DVI fed video. It's that good. Of course, DVI is much simpler, as you don't have to have everything tweaked just perfect to have everything map just right. It should be a nice convenience.


Either DVI or analog VGA will look excellent.
 

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You vanity for 85 horizontal pixels? Did you have an application where you really need to address them?


The only thing I can think of is critical work with 4:3 computer images where you must have square pixels (SXGA pixels aren't quite square).
 

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Discussion Starter · #5 ·
Thanks for the great replies so far.


> The short answer is that DVI-I or DVI-D can easily handle the native resolution of SXGA+.


Thanks. I was concerned, because one thread I was reading (which I can't seem to locate anymore) talked about this subject and people seemed to be taking it for granted that the DVI-input on the 150CL could only do up to 1280x1024.


> Faroudja might have meant that IF it were possible, the NRS should be set to a 1360x1024 resolution.


Perhaps. It is sort of eyebrow-raising that they worded it the way they did. It answered the query but skirted the fact that the Hitachi 5500 couldn't properly handle the signal the NRS+ would be tailored to send to it.


Speaking of Faroudja's NRS+... I caught a thread where people were talking about it and the DVI input on the 150CL. Specifically, the person who started the thread was seeking recommendations for scalers. It was mentioned that the NRS's DVI support was "lacking" vs other models.


Since Faroudja is supposed to have a heritage of sorts for providing the best products, I found this a little disturbing. If I got a 150CL and wanted to use the DVI almost exclusively, would the Faroudja NRS+ be a poor choice? If so, what then would be a "good" choice?


> You vanity for 85 horizontal pixels? Did you have an application where you really need to address them?


The 1365x1024 panel is a fully digital 4:3 panel with perfectly square pixels. There are methods for taking full advantage of this accuracy. These projectors cost at least six thousand dollars by themselves. There's no need to make it sound as though I'm being unreasonably finicky in my pursuit of solutions.


> The only thing I can think of is critical work with 4:3 computer images where you must have square pixels (SXGA pixels aren't quite square).


A good example. In fact, I'm a little divided on the Panamorph issue, and haven't yet decided if I'll get one. Extra resolution = good. Pixels with a 4:3 aspect ratio = bad.
 

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Quote:
The 1365x1024 panel is a fully digital 4:3 panel with perfectly square pixels. There are methods for taking full advantage of this accuracy. These projectors cost at least six thousand dollars by themselves. There's no need to make it sound as though I'm being unreasonably finicky in my pursuit of solutions.
Fair enough sir. But consider: is this panel really fully digital? It has an analog RGB input. And an onboard scaler which perhaps can't be bypassed (even for DVI input?) and which may preclude perfectly resolving a 1365x1024 signal.


If the Hitachi's DVI input can be made to bypass the internal scaler and correctly display its native 1365x1024, then and only then, am I willing to call it a fully digital panel.
 

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Discussion Starter · #7 ·
> If the Hitachi's DVI input can be made to bypass the internal scaler and correctly display its native 1365x1024, then and only then, am I willing to call it a fully digital panel.


Well, in the Hitachi's case, I don't know if one can bypass the internal scaler (my guess is 'yes'). But it's now been fairly well-established that the 5500 can only accept up to 1280x1024, due to a lack of ability to differentiate between that resolution and the full 1365x1024. This is the point which essentially erases this model's prospects for residence in my living room. The quality control problems and lack of configurability only compound the issue.


Going by the criteria you listed, I think the 150CL is the only LCOS projector that could be said to have a fully digital panel (or at least it's the only remotely affordable one.. and I use that word very loosely).
 

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It sounded like the 1280 horizontal limit was mentioned in the context of the analog RGB input, perhaps not the DVI input. If the DVI can support pixel perfection maybe this panel is still in the running for you?
 

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Discussion Starter · #9 ·
> It sounded like the 1280 horizontal limit was mentioned in the context of the analog RGB input, perhaps not the DVI input. If the DVI can support pixel perfection maybe this panel is still in the running for you?


Hmm. If pixel perfection can be achieved via DVI, then yes, absolutely. Unfortunately, all the discussions I've read about this particular limitation never indicated that there just may be a way to achieve 1365x1024. Not even email from Hitachi employees. They even went so far as to specifically admit that the Hitachi 5500 can't be upgraded by any means, which sounds like a nail in the coffin.
 

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no pixel perfection on RGB or DVI no fix coming fron Hitachi. They are looking to do it on future models, but also no new lcos till next year
 
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