NTSC monitor setup Zero or 7.5?

[Scott Chapin]

Preston, I'm not feeling alone anymore. Sony Professional had to transfer me to engineering, who in turn could not understand why I would want the cameras analog output to match the monitor. Seems like there's much confusion all around.

I thought of temporarily setting my camera to 7.5 and adjusting the monitor brightness, but Sony said that wouldn't work. I'll go with you on that one :-).

Thanks,

[Bill Peterson]

First … thanks all for tackling the problem. There seems to be a wealth of misunderstanding about the issue. It’s important to everyone that is trying to make the best looking DV we can.

I’ve been reading and testing and scratching my head, and spent most of the day and last evening (till about 1am) plugging and unplugging, looking back at what you’ve said and the like.

Here’s what I did:

1. took my Panasonic DVX100 and switched it to bars … camera set to zero.
2. took my (new) Panasonic AG-DV2500 DV Deck … which by the way has “Setup” and you can switch between Setup and Off. Which is 7.5 and 0.
3. I plugged the DVX100 into the AG-DV2500 (camera at zero) and fed it the bars. I set the Deck to “Setup ON” (7.5).
4. I plugged the AG-DV2500 into the Monitor (Sony PVM 1354Q) I set the Monitor switch to 7.5 in the menu. I adjusted the bars to show what I understand to be the proper Pluge.(left two merged into one another). I then played a carefully lit scene from the deck and it looked good as well.
5. I unplugged the Deck from the Firewire cable and plugged the camera’s Firewire cable into my Canopus break out box and captured the same bars (via Canopus DV Capture)
6. I started Premiere 6.5 and imported the same bars to the timeline.
7. I plugged the Firewire cable back into the Deck and played back the bars through the deck to the monitor (7.5 & 7.5 setup you could say). The bars looked the same.
(The monitor is still at the 7.5 setup just established for the feed from the Deck)

Seemingly if I go through the AG-DV2500 Deck and leave it’s output to “Setup On” (7.5) and the monitor to 7.5 setup on the camera’s bars, then everything seems to be “inline” for me. But what about the comment that the left pluge bar should be visible if you are feeding 0 bars. Does the 2500 Deck overcome that problem in this setup?

If I plug the Camera directly to the monitor via the S-video cable with leaving the monitor at 7.5 then the Camera fed bars at 0 are too dark. Switching the camera bars to 7.5 makes it look right again.

Now switching the camera, with a 0 bars direct feed, to the monitor and switching the monitor to 0 seems to make the bars a bit too bright, if they are to match the response of the previous 7.5 setup via the deck. To make the pluge look the same you must tweak the brightness knob a bit darker.

Ok ... so now what have I got wrong? And if I take the monitor out to location and plug the camera into it to tweak in the prefect scene... Do I set camera to 0, monitor to 0 and tweak the pluge down to the left two going away and the last one remains or what?

Thoughts welcome from those smarter, more experienced or more opinionated than I about what this all means to us all?

Thanks again for all the thinking and testing and typing to help clear up the thinking on this subject.
Thanks
Bpete

[Preston Herrick]

Steps 1-7 look good. You've got it. Theoretically, once you have the monitor properly adjusted (like you've done) you should be able to feed the camera directly to it (with camera set to 0), switch the monitor to 0 and have everything be the same - and correct. Bottom line is: your monitor and source should have the same settings - 0 to 0 or 7.5 to 7.5. With all things being equal, coming out of Storm or your deck "should" produce the same results as hooking your camera direct, but some discrepancy isn't out of the question (due to signal loss or whatever). A minor tweek to the brightness can bring everything back in line. If it requires a huge adjustment, then something isn't right.

So, if you take your monitor out in the field, leave your camera set to 0 (you don't want to shoot with setup by mistake) and switch the monitor to 0 IRE on the input. It may need to stay on for 10 minutes or so to warm up. Feed bars, tweek if necessary (left and center plunge should match, right one brighter), go for it.

BTW, your quote: "But what about the comment that the left pluge bar should be visible if you are feeding 0 bars. Does the 2500 Deck overcome that problem in this setup?"

Once properly adjusted you shouldn't see the left plunge bar. That will occur however if you send 7.5 bars with the monitor set to 0. Everything will be too bright. The other instance would be if you don't have a switchable monitor (fixed at 7.5) you would have to adjust the brightness higher when feeding it a 0 IRE signal, and then eyeball things. In your case, don't worry about it.

[Bill Peterson]

Thanks Preston,
That's great to hear. If you don't mind, one more spot where I might be slightly confused.

>>>>Earlier post Bill wrote: do this correctly, as I understand it, you need to adjust the brightness on the monitor until the left two pluge bars on the NTSC colorbar chart disappear into one another.<<<<<<<<<<

I adjusted my monitor as he describes, is that correct? Or is there something slightly different in your description >>>>(left and center plunge should match, right one brighter), <<<?

I had taken the instructions I read to say that left and center should disappear into black, with the center being "just invisible," I think was the quote, and the right most bar visible. So if I'm off tweak us over to "just right" if you please.
Thanks,
Bill

[Preston Herrick]

That's correct. At this stage you're dealing strictly with luminance or brightness. Your focus is on the first two plunge bars. You want the middle one to just disappear into the first so that they appear as one - no division or apparent difference between the two. As soon as they "merge", stop.

[Scott Chapin]

So what do you do when the monitor has setup only? Do I change the camera to 7.5 long enough to tweak and then switch back? Or can I turn the brightness up on the monitor with the camera at 0...a safer maneuver.

[Preston Herrick]

Hi Scott. You and I are in the same boat in that our field monitor's are fixed and expect to receive a 7.5 signal. That means starting with a properly calibrated monitor, leaving the cam set to 0, and turning the brightness up as described here (Step 1 of second half, bottom of page):

http://greatdv.com/video/smptebars2.htm

A pain in the butt to be sure and a certain amount of guesswork no matter how you cut it.

[Scott Chapin]

Thanks Preston! A terrific link. The info on adjusting Premiere's color bars was great, if only to know what the RGB values of the color bars are.

[Don Donatello]

don't know about the DVX 100 color bars ..

but in general
601 SMPTE color bars

RED 180 16 16
G 16 180 16
B 16 16 180
WHITE square 235
1st bar on left 180 180 180
3 pluges = middle is 16 16 16
left of middle 7 7 7
right of the middle 26 26 26 but have seen em anywhere from 26 - 41 across ...

______________________


RGB color bars
R 255 0 0
G 0 255 0
B 0 0 255

white square 255 255 255

[Scott Chapin]

<<<-- Originally posted by Don Donatello : don't know about the DVX 100 color bars .. -->>>

Which has me going now, because the DVX100 color bars don't look true in the LCD. Perhaps I should capture some and take a look at the file's colors.

[Preston Herrick]

Scott, I'd be willing to bet the DVX generated bars are fine. It's LCD displays I don't trust. They have a ways to go in terms of color, contrast, resolution. Nothing like a good 'ol CRT.

By the way I've captured bars and sampled them before in photoshop. Not always dead on in each color channel (probably due to compression, etc) but within 1 point of correct RGB values - not enough hurt anything.

[Bill Peterson]

LCD ... yeah a ways to go.
I did all the setting up as posted above and then to cap it off while still plugged in to the monitor, I went in to the DVX LCD set up and tweaked it till I got it right on the pluge. Then I took a well lit talking head shot that looked real good on the tweaked monitor and worked to get the LCD looking as close as possible. It looks a lot better than I had it before. My .02 worth.

Bill

[Tony Hall]

Question: What setup level do you use on your video monitor when editing video. I use an XL1s and I pretty much just use the setup for contrast control and I have no idea what the actual setup of my video is. So, should I set my monitor to 7.5 or 0?

[Tony Hall]

Ok, I think I've figured something out. I know there's a whole lot of confusion and discussion on the subject, but I think it's a whole lot simpler than many people think.

First, I went to Adam Wilt's website and found out that no DV device records video with setup and no consumer level gear has an option to output video with added 7.5 setup. 7.5IRE setup is only for broadcast and DV users need not bother with it unless they intend for their footage to be broadcast and even then the station would probably do that for you anyway.

Cameras that claim to add setup/pedastle are only simulating different setup levels for visual effects because the actual footage still has a 0IRE setup level.

So if you, like me, are using a consumer level camcorder as a deck, you know that it's certainly not adding setup to your video, so you can set your monitor to 0IRE for setup and calibrate it like that.

My only test was comparing the color bars that come with Vegas to the color bars on the XL1s. They showed up identical on my monitor.

What's really funny though is that I really don't think it matters what you have your video monitor set to as far as setup level. Why? Because if you calibrate your monitor to color bars AFTER choosing a setup level, it will show the exact same thing whether it was 7.5 or 0.

The only question I have left is this: I calibrated my monitor using the method that people use when using a 7.5 setup. With the left two pluge bars being the same. These two bars are both visible and different in my XL1s viewfinder and on my computer monitor in vegas. Are we supposed to calibrate differently when using a 0IRE setup?

[Tony Hall]

Damn, I feel dumb replying to my same message again, but I think I figured out why the middle pluge bar is supposed to be black on a video monitor. In the waveform monitor in Vegas the middle bar is 0IRE and the left bar is below 0, hence it being called super black. So, when you calibrate your monitor you just want to make sure that the part of the signal that's 0IRE is black on your monitor. That just answers the question I asked above I think.