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Discussion Starter · #1 ·
I have a Zenith HDV420 OTA receiver, it lets me pick between 1080i, 720p, 480 p and i. My Z2 is native 720p, so do I set the receiver at 720p or at 1080i? Dont know which one would be better, native for the projector or native for the broadcast...
 

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There are two schools of thought. Some people think that feeding it the true native resolution (720p) will produce the cleanest image. Others say that giving it the highest possible image and letting the internal unit downscale it will give you a better picture. Thue is right, it's going to be a personal choice.


-MP
 

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Have the OTA box output 720p. If it had a native pass-thru option then you'd have a choice to make, but since it doesn't you want to avoid scaling the source twice.


If the OTA box outputs 1080i than you've guaranteed the source will have to be scaled at least once by the Z2, but if you let it output 720p and the

source is already 720p (ABC,ESPN) then no scaling is necessary and worst case the source would only be scaled once.
 

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Shagn,


I just got my Z2 and initially had my D* receiver set to output 1080i. After switching it to 720p I seem to notice a slight descrease in visual noise and pixel (as in pixels in the digital signal) structure. I've only had this thing for 3 hours, though, so I'm not a definitive source of information...yet.
 

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Quote:
There are two schools of thought. Some people think that feeding it the true native resolution (720p) will produce the cleanest image. Others say that giving it the highest possible image and letting the internal unit downscale it will give you a better picture. Thue is right, it's going to be a personal choice.
Great advice.

CSI in HD... sweeeeeeeet! :)
 

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If the projector is natively 720p, you should set the box to output 720p. That way true 720p sources (ABC, ESPN) will not need to be scaled. If you set the box for 1080i output, a 720p signal is scaled up to 1080i by the box, then scaled back down to 720p by the projector. No need to do that.


1080i sources need to be scaled down to 720p regardless. 720p output makes the most sense.
 

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Would this hold true for the Z1 as well? I have my HD directv receiver set to output 1080i if the source is 720p or 1080i. Is this wrong? Am I somehow 'damaging' the HD picture by scaling it?
 

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When KBK (Ken) showed us the new Action 1 projector on the weekend he sent it a 1080p signal from his HTPC and let the PJ scale it down to it's native resolution. The picture was flawless.


Not everyone agrees with this method but I sure do.

In the end... look at both and decide for yourself. Some people get too wrapped up in numbers and forget to use their eyes.

What looks better to you?
 

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hoops,

2 things


1) Your pj is native 960x540 (1/4 of 1080) so outputting the source at 1080 should be better for your Z1


2) Don't sweat it, just try each and see how it looks, pick the one that's better.
 

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Ideally, you'd need 2 projectors, one native 720 and one native 1080, but we don't have that.


It all depends on who has the better scaler, your box or your pj. If your pj is 720p native then you definitely want ABC, ESPN, and FOX (when they go HD) to be output at 720, that way nothing gets scaled, it should look as good as it can. A passthrough option on the HD box would be best here, meaning it passes the original 720p signal through without changing it and it matches the native resolution of your pj.


Now if your pj is 720p and you're watching CBS HD at 1080, now you have to decide if you want the box to scale it to 720 to match your pj resolution (in which the pj won't have to scale it), or do you want the box to pass on the 1080 signal and let your pj scale it to its 720 native resolution.


I'm not sure there's a hard and fast rule for any of us given the endless combinations of boxes and pjs and scaling software and chipsets, etc...


I'd probably vote for pass through if that's an option (that's what I have mine on--I have a 960x540 panny until I get my 720 hooked up tomorrow). If that's not a choice then try it each way and see what happens. I guess worst case scenario you have to manually change the output on your box when you flip over to ESPN.
 

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Quote:
Originally posted by hoops10
I have my HD directv receiver set to output 1080i if the source is 720p or 1080i. Is this wrong? Am I somehow 'damaging' the HD picture by scaling it?
If it's a 1080i HD picture you're not harming anything. The receiver just passes the signal through and let's the projector scale it, which has to be done anyway.


However, if it's a 720p HD picture, you're scaling it up to 1080i and then back down to 720p. This is bad because the majority of scalers out there (both in HD receivers and in projectors) halve the 1080i resolution by just reading the first 540 fields, then bob & weave that to 540p and scale it up from there to 720p. So you've irrevocably lost important bits of picture information and replaced them with pixels duplicated from the first 540 fields. Not recommended.

Quote:
Originally posted by Kysersose
When KBK (Ken) showed us the new Action 1 projector on the weekend he sent it a 1080p signal from his HTPC and let the PJ scale it down to it's native resolution. The picture was flawless.
If the scaler can bob & weave 1080i to 1080p before scaling it down, that would be the ideal way to do it. Unfortunately, it's only a small number of expensive scaling chips that can do this currently.
 

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Josh: So you recommend this setup then:


If material is 720p, ouput it to 720p.

If material is 1080i, ouput it to 1080i.


I am using a Z1 that , if I remember correctly, is 1/4 HD. Does that matter?
 

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Discussion Starter · #15 ·
For my Z2, I'm thinking it makes sense to use 720p on the HD tuner. If the projector is going to be using this mode one way or the other, I think it makes the most sense to send it the 720p signal to begin with...
 

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Like hoops10 said: If the source is 1080i, I set my Dish 6000 to 1080i, if it's 720p I set it to 720p, I seem to get the best results that way.
 

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jacksonian, what do you mean? The 6000 has to be manually selected for whatever output you want. If you mean the PJ, it only has Pass through for SD material.
 

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Quote:
Originally posted by jacksonian
Marissadad, doesn't your Dish have a pass thru option that does that for you?
My new HTL-HD certainly does. It's called Variable 1 mode. Though, when using DVI, it apparently passes the signal through without any options whatsoever for changing the output resolution.
 
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