Quick Q: Does pattern size need to match when comparing 2 pattern sources? - AVS Forum
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post #1 of 5 Old 04-18-2013, 11:18 AM - Thread Starter
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I'm using an Iscan Duo as a signal generator and a WDLive TV media player displaying the AVSHD patterns in the "Calman Windows" folder. I'm using 32% (10.24% of screen area) for the Duo but the AVSHD patterns are a bit larger. My main concern is whether this difference in size affects the x,y readings?

Seeing:

- Even reference generators do not output exactly the same
- I don't really know the % RGB from the AVDHD patterns matches the % RGB from the Duo (which is R19 G19 B50 for blue 75% stim. 75 sat. when rounded up)
- I don't know the WDLive tv is outputting a reference signal when displaying the patterns

How can I compare the patterns? A quick comparison of the x,y coordinates show the measured values are pretty close although x for red and y for cyan are off (I know the i1 pro 2 I use does not deviate more than 0.001 most of the time and 0.002 at the most)
White Red Green Blue Cyan Magenta Yellow

0,0005 0,0026 0,0004 0,0016 0,0014 0,0013 0,0010
0,0002 0,0002 0,0016 0,0017 0,0042 0,0012 0,0002

edit: forgot some useful info. I'm measuring a Panasonic Plasma

My gear: Panasonic TH-42PF11EK pro plasma display. -- Iscan Duo video processor -- i1 display 3 colorimeter -- i1 pro 2 spectrometer
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post #2 of 5 Old 04-18-2013, 12:00 PM
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For a plasma, yes the absolutely do matter.

Pattern size effects APL, which affects measurements.

Joel Barsotti
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post #3 of 5 Old 04-18-2013, 11:39 PM - Thread Starter
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Just to make sure I got the message: also x,y will be affected by the ABL and not only Y? Although the x,y deviation numbers for most colors are pretty low (especially for white), they are a fair bit worse than the i1 pro 2 repeatability checks I did some time ago.There many more numbers had a variation in the 0,000x range whereas here they are more in the 0,001x range. If it is the ABL, I will bump the Duo pattern size up to match the AVSHD pattern size and see whether the numbers improve.

Do you happen to have an idea what effect the rounding of the RGB % wil have in terms of x,y 0,xxxx?

My gear: Panasonic TH-42PF11EK pro plasma display. -- Iscan Duo video processor -- i1 display 3 colorimeter -- i1 pro 2 spectrometer
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post #4 of 5 Old 04-19-2013, 07:35 AM
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Quote:
Originally Posted by Jeroen1000 View Post

Do you happen to have an idea what effect the rounding of the RGB % wil have in terms of x,y 0,xxxx?

No, it's completely display dependent, and even then based on the current settings for the display.

The only way to find out is through measurement.

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post #5 of 5 Old 04-19-2013, 12:08 PM
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You can't categorically say that ABL would only affect Y measurements and not xy. You'd want that to be true, but there's no guarantee it will be true.

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