Setting NTSC parameters on the cheap

BillyBoy wrote on 5/5/2002, 10:56 PM
One often overlooked area for those new to video editing is proper calibration of any monitor you use to monitor your editing results and of course the calibration of any TV you plan to play created DVD's or VCD's off of. If you skip this important step any adjustments you make in Vegas Video to levels, hue, saturation and luminance or the more advanced tweaking of color curves, other FX filters in spite of your best efforts may still look a little off once viewed on your TV. This of course is not meant for professional use, however I feel there are a lot of people like me using Vegas Video for hobbist purposes. This information is targeted to those people.

Not surprising there are several DVD titles on the market that walk you through the steps. In my opinion a pretty decent one is Avia Guide to Home Theater by Ovation software which you can usually find at larger web sources like Amazon. You can grab a copy and follow the much more detailed steps or in a pinch here are a few simple suggestions where you can just eyeball it.

Surprise, many people crank up the brightness and contrast on their TV sets way past the ideal level which actually reduces the overall quality and fidelity of the image. Before making any adjustments you should let any TV set warm up between twenty and thirty minutes to allow components to stabilize.

The first adjustment should be to set the black level, more commonly called brightness. The above mentioned title includes several real time test patterns to get the settings more precise. Results can't match a lab, but after all most of us aren't making commerical grade videos that need to meet broadcast levels. :-)

To eyeball if or not black level is set correctly, just watch your TV and take note of those very brief times when the screen goes blank most commonly at the start or end of some commericals. Your TV screen at those times should be totally black. If it is any shade of gray, even a little, then you cracked up the brightness too high. Not only are you viewing a distored picture that you've just gotten use to over time, brighter than normal images take more high voltage and over time if you leave your set that way it will likely need repair more frequently.

Without any test pattern you'll have to slowly reduce brightness a step at a time until you return it to the proper levels. If you've been use to watching TV this way for years it will take a little getting use to (several days) because for sure the picture will look too dark compared to what you were used to. Most likely in part because you also have the picture (also called contrast) too high as well.

Again with test patterns simple to adjust. To eyeball it look for distortion in vertical lines. If you can restore vertical lines to straight up and down without bending by reducing the picture level control, (contrast) then you corrected another common problem. If you can't then your convergence is off. After correcting the picture level go back and see if brightness needs a little more tweaking. These two controls interact with one another so you may need to go back and forth several times to get the best results. Also be sure to make adjustment at the time of day you do most of your TV viewing with room lighting as close as possible to what you usually have.

The last general adjustment is to adjust sharpness. Again a lot of people think more is better and push the control near or all the way up. It has the reverse effect. This is more subjective then the other settings. Most TV's I've seen have the best sharpness with the control between 30-40% of maximum. Anything beyond that and you are likely to reduce rather than improve overall picture detail. This is also true of over cranking the contrast. If you're guilty of that what you're doing is reducing detail in the shadow area of images so you'll see less, not more detail.

Setting proper color balance is a little trickier. There are several web pages that offer some simple procedures using color bars. Do a web search for NTSC color bars and also try NTSC test patterns. One example: http://www.videouniversity.com/tvbars2.htm

Ok, that's a brief overview.

Why would you want to go through the trouble? Because if you're going to spend hours, alright days tweaking your videos, then you want to view them under the best possible conditions. As you gain experience and start using the many advanced filter options part of Vegas Video you'll see even minor adjustments can make a rather dramatic improvement. Don't forget to calibrate any monitor you've hooked up to view the preview window in which is a better option then just adjusting off your computer monitor. If you must do it that way, make a test video of a still image and drag it across the timeline so you can apply various degrees of correction then burn a CD and see which way you need to lean to offset differences between how the video shows on your monitor and TV. This was the method I used prior to getting my digital camera. You can get pretty close with trial and error, but making adjustments in Vegas Video while viewing a connected TV monitor (not a second computer monitor) is a superior method.

Comments

SonyDennis wrote on 5/11/2002, 6:37 PM
Agreed. Before DVD's came out with THX Optimode tests, I used the "Video Essentials" disc, and found my TV had the Sharpness turned up too high. You get get detail where it doesn't exist, and this control is usually too high. Turning it down, to where the test pattern no longer showed ringing, made movies look *so* much better! It was worth the time to do the setup. I've heard great things about the AVIA disc too.
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BillyBoy wrote on 5/11/2002, 9:11 PM
Yea, it is a pretty comprehensive disk. Setting up to NTSC specs (close) without any color bar generator or other goodies most people don't have is just a small part of it. It is marketed to people setting up a home theater and walks you through all the steps of hooking up, placing and tweaking the various components.

I was guilty too of having my sharpness control on my big TV pushed way up, because I didn't adjust it to a test pattern. Once I did, and a couple days of getting use to it, you do start to see more detail, not less.
Stiffler wrote on 5/12/2002, 1:48 AM
BillyBoy...Thanks for the guide. I just bought a new TV and every thing seems out of whack, so this will be helpful.

Do you think it makes a difference what sorce my video is coming from for this? I have DVD with 'component' cables, DSS with an S-video connection, and my VHS with a composite video cable (yellow RCA type)?
BillyBoy wrote on 5/12/2002, 12:34 PM
Your welcome. Only because the picture quality should be better I would use a digital source if you can. To avoid the remote possibility of burning in a image into your TV screen don't leave any single stationary image for more than five minutes or so. Allow the system to warm up for at least 20-30 minutes before making any adjustments.

Actually talking about this brings back memories when I built my Heathkit TV around twenty years ago. Ouch, now that I think of it more like thirty years ago.
SonyDennis wrote on 5/12/2002, 5:51 PM
The issue I've had with this is that my Dish receiver has a different black level than my DVD player. I have to bump Brightness "2 clicks" when I switch to DVD. Someday, I'll upgrade to a DLP projector, but that's another project...
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bakerja wrote on 5/14/2002, 10:35 AM
VV3 has test patterns built in that are quite usefull also.

JAB