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CamG said:
Sorry guys, that's what I meant vertical bars...not horizontal..... That's why I was confused when jvincent (post # 172 above) mentioned that the below black was cut off.
When I said clipped, I meant that the below black bar was not differentiated from the reference black bar. All the bars are visible via component.

There should be three bars.

Below black = RGB = 0 (digital value)
Black = RGB = 16
Grey (Not sure what the value is)

Via component, the below black and black are transmitted at the same analog voltage, so the 8300HD is either truncating values below 16 or expanding the video range so that 16 -> 0.
 

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http://www.mediacollege.com/video/test-patterns/colour-bars-smpte.html

This is the link Marc posted in message #159. If you look at the picture of the bars you'll see very clearly what is meant by 'pluge'. It's at the bottom right hand corner.
I recorded the bars and just checked to see exactly what I can see in the pluge area. I have a crt tv and the 8300hd pvr, connected by component cables. As mentioned earlier, the blacker than black bar doesn't show. I'm curious if the HDMI connection would show 'super' black. Seems odd that the 8300hd is clipping the blacks when using component cables.
Anyway, you can still set brightness by adjusting the level until the small dark grey bar at the bottom JUST shows. Hope this helps.
BTW the pluge bars in the illustration are purposely boosted so that you can see them. In reality your settings shouldn't show like that.
 

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Harl said:
I'm curious if the HDMI connection would show 'super' black.
I calibrated both outputs of my 8300HD, and below black DOES get passed via HDMI.

FWIW, after calibration, I eyeballed the brightness for component until the grey bars in the pluge matched between the two outputs, the picture quality is very close between the two. HDMI is indeed better, but I'm using component right now because the HDMI handshake issues on the 8300HD annoy the hell out of me.
 

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I used the CBC HD test pattern to check my Shaw 6412 cable box and my Toshiba TV. The Toshiba only has component input, no DVI or HDMI, so I use component video cable connections. I could not get the blacker than black bar to show, although I did not spend that much time trying. I just adjust it until the slight above black bar was still showing but just about to disappear into background black.

MY picture looks pretty good for HD content so I am not too concerned about it now.
 

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Same for me and my SA8300HD and Panasonic TH42PHD7UY
I find the HDMI a little grainy (gets better with less brightness) and prefer the component.

Good job, thanks Marc!
 

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jvincent, Thank you for taking the time to clarifying that for me.. Now I understand. ( this is still new to me )

So now I really don't understand why I cannot see any bars at all. It is one big black rectangle... no separation between the different blacks... something is just not right here with my set....

I am using a 6412 with component out.

Thanks,
Cam
 

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It's very odd that you can't even see the grey bar.

Does the 6412 or your TV have an adjustable pedestal or setup level by any chance?
 

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CamG, a few things could be causing you not to see any grey.

1. Have you turned off any "automatic" settings, like auto-colour, black level, etc. If those are on, the adjustments may not have any effect.

2. You need to adjust Brightness (Black Level), not Contrast (White Level).

When you adjust the Brightness, can you see a difference on "regular TV"? If not, then perhaps something is blocking the user settings.
 

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Thanks for the help on this.
I have no auto settings enabled and I turned my Black Enhancement to Off. That helped a little as now I can see one of the pluge bars when I turn the brightness up. I believe it to be the lightest 11.5 bar on the right. I still cannot see the two on the left.

Cam
 

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hd test pattern ?

Anyone know when cbc will be running the test pattern again ? I have been away for some time from this forum.
 

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Test Pattern Gone In The Fall

FYI
CBC Television will be running 24/7 in the fall. At that time, the test pattern will no longer be available. Line up your displays over the summer!
 

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Nostalgia question

Marc said:
FYI
CBC Television will be running 24/7 in the fall. At that time, the test pattern will no longer be available. Line up your displays over the summer!
Out of sheer curiousity, do you know where I can get my hands on a hi-resolution gif or jpeg (or whatever) of the old "Indian chief in a circle" test pattern?
 

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HD Test Patterns and Calibration: Detailed Technical Discussion

There's some good test pattern files here,
http://www.belle-nuit.com/testchart.html

Marc, is it possible to put a computer file on CBC, if so some better ones can be used, for this last sprint of summer test patterns. I helped provide the colorbar generator in the open source program, Avisynth (www.avisynth.org) and am able to create or validate standardized test patterns.
I'd be happy to create some and provide them in a Creative Commons or other license to enable CBC to legally use them.

ps supplying an mpg file is the only way to ensure the colors are accurate, as I found out, some colors cannot be perfectly converted from RGB (of a picture file) to the YUV of video (especially the color yellow :). MPG colors would be generated in native YUV, and could be verified exactly by the recording from a computer HDTV tuner.
 

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A problem with CBC-HD test patterns: did upconversion cause a color conversion?

A question in plain english for the rest of you: in the shaded yellow area, do you see a white bar at the right side, also does anyone see a blacker than black area. Also, the slightly brighter than black area is within the letters "Corp" of "Corporation".

Now for something completely technical.

First, some very good patterns at http://www.w6rz.net/. EDIT Stampeder: these patterns are in ".ts" transport stream format.

Second, the test patterns I measured digitally were close to Rec. ITU-R BT.801-1, Annex 2, P13-15, but slightly brighter with some colors wrong.
Also, they were Rec.601 YUV values in a stream which should be Rec.709, in other words I was expecting a different set of YUV values.
You can tell this kind of error when the green bar seems unusually bright (Rec.601 decoded via Rec.709 matrix to RGB).

To put this in plain english, did the upconversion box force a color conversion?

I'm not 100% positive of my test methods, but still the resulting values are not perfect. This would be expected of a color conversion.

Also I did not receive <16 or >235 values of Y.
 

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jmac698, I'm very interested in what you are offering Marc and the CBC regarding test patterns. For our Home Theatre enthusiasts in layman terms, what would be the benefit of your test patterns over the ones currently use by CBC-HD?

thanks!
 

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jmac698 said:
Also, they were Rec.601 YUV values in a stream which should be Rec.709, in other words I was expecting a different set of YUV values.
You can tell this kind of error when the green bar seems unusually bright (Rec.601 decoded via Rec.709 matrix to RGB).

To put this in plain english, did the upconversion box force a color conversion?

I'm not 100% positive of my test methods, but still the resulting values are not perfect. This would be expected of a color conversion.

Also I did not receive <16 or >235 values of Y.
jmac, which patterns are you measuring? The broadcast ones or the one's in the link provided.

Earlier in this thread I asked Marc about the colourspace decoding and his answer was that they were supposed to have been encoded with Rec.709.

The entire 601 vs 709 colour space thing can be very messy. I can't remember if the test patterns at the link you provided are encoded with 601 or 709 but even if they are encoded properly some of playback machines will "decide" to decode 610 or 709 independant of how it is encoded.
 
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