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Intensity Pro analog component output type

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Alan Okey
Intensity Pro analog component output type
on Apr 20, 2010 at 1:15:57 pm

I'm monitoring the component analog output of an Intensity Pro (downconverted to SD-NTSC) on a Sony PVM-20M2U. The monitor has a choice of three different settings for Component Level:

N10/SMPTE
Beta 7.5
Beta 0

Which is the proper setting to use for monitoring component analog SD (NTSC) from the Intensity Pro?


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Fred Jodry
Re: Intensity Pro analog component output type
on Apr 22, 2010 at 2:02:28 pm

Alan, since you are using standard output instead of one for Beta, the N10/ SMPTE one is the standard to use on the monitor when running NTSC, and in some other cases. Now let`s look at the trouble you weren`t going to get into:
In point of fact, since you are feeding a display monitor and looking at it you can probably make a proper display on the screen, both background brightness and acceptable drive, by adjusting within the reasonable range of the brightness and color/contrast "knobs?" on the monitor as you use any of the 3 settings. (If the brightness range on your Sony doesn`t have a wide enough swing, break out your circuit diagram and soldering iron and get to work.) The real test is not whether the Intensity Pro`s output looks right on the monitor, which it will usually pass even if it`s wrong in certain directions but how it looks on the oscilloscope. Feed properly adjusted color bars or other test signal input into the Intensity Pro`s recording then feed out the playback to a properly terminated oscilloscope (which can be in line with the monitor and whatever else is getting fed) and look for proper signals on the oscilloscope`s display. A good stored test recording can substitute. You`re then set up and ready to monitor your camera or similar.
Below, is a list of voltages for color bars as Pr, Pb, and (Y?) for N10/ SMPTE.

"Their (color-difference signals) amplitudes are expressed in percentages of the full amplitude primary signals (700 mV). These signal amplitudes are reduced by scaling factors to meet specific signal amplitude range requirements. When the allowed amplitude range of these signals is 700 mV (±350 mV), as specified in the EBU N10 Standard and the ITU-R BT 601 recommendation, the color-difference signals are given by the following expressions:

E´CB = 0.564 (E´B - E´Y), also known as PB in North America
E´CR = 0.713 (E´R - E´Y), also known as PR in North America"

Intensity Pro analog component output type
by Alan Okey on Apr 20, 2010 at 9:15:57 am
I'm monitoring the component analog output of an Intensity Pro (downconverted to SD-NTSC) on a Sony PVM-20M2U. The monitor has a choice of three different settings for Component Level:

N10/SMPTE
Beta 7.5
Beta 0

Which is the proper setting to use for monitoring component analog SD (NTSC) from the Intensity Pro?


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Jeff Pulera
Re: Intensity Pro analog component output type
on Apr 23, 2010 at 7:28:39 pm

Hi Fred,

That's a pretty deep response. I am in no way, shape or form a video engineer, but I've been editing a good long time and have NEVER seen the words "N10/SMPTE" in print before and had to Google it. I found this on the Cow -

http://forums.creativecow.net/archivepost/150/679978

In my experience with Matrox NLE hardware over the years, they've had an "Analog Setup" option that could be either 0 or 7.5 IRE (0 default). While the US standard is 7.5, all Japanese-made camcorders shoot at 0 IRE, so 0 has always been the recommendation (for DV sourced material) when video is output/previewed via analog from NLE.

Setting to 7.5 would wash out the blacks on the analog preview, fooling the editor into color correcting to compensate (when in reality the signal was fine to start with, and would've looked good as output to DVD or back to DV tape).

My recommendation will be to try the Beta 0 setting, then try the 7.5 and see if the blacks look noisy or washed out. I bet you're happier with the 0 setting

Jeff Pulera
Safe Harbor


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Fred Jodry
Re: Intensity Pro analog component output type
on Apr 23, 2010 at 9:01:22 pm

Jeff, Alan is setting the background ranges of the (knobs?)on his MONITOR (cathode ray tube display or similar). Anything that works and still leaves range for adjusting works, just like a tv. When it comes to making video in the first place, Both NTSC (National Television Standards Committee) and NTSC 2 (color tv committee around 14 years later) made the black pedestal 7 1/2 IRE units above zero, the positive plateau of "untilted" synchronization pulses. 5 to 10 IRE are accepted limits and can be seen as reasons of gamma correction or simply acceptable error. When making NTSC video that "goes somewhere" in this world, use it or you`re out of specifications for the composite signal. RGB lines going out of a camera head towards the combiner or encoder are examples of zero pedestal black uses and not the composite signal yet. Which pedestal and voltage gain he uses depends on the part of the operation. If we read Alan`s inquiry again carefully, I seem to remember that he`s asking about an RGB- style input, maybe Pr, Pb, Y, where Pb and Pr probably have zero pedestals compared to clamping but can maybe, maybe go both positive and negative of it, and the Y signal probably also has a zero pedestal but only goes positive. Pb, Pr, Y is really a mixing level brought up to annoy red, green, blue, ("already mixed" spare luminance, like keying etc.) and synch. cabled video users. SMPTE is a modern committee or really an engineering society.


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Alan Okey
Re: Intensity Pro analog component output type
on Apr 24, 2010 at 12:54:07 am

[Fred Jodry] " If we read Alan`s inquiry again carefully, I seem to remember that he`s asking about an RGB- style input, maybe Pr, Pb, Y"

Exactly. I was asking specifically about the Y, Pb, Pr component video output/input of the card and monitor, respectively.


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