BillyBoy.....Question for you.

craftech wrote on 11/5/2003, 7:45 PM

Bill,
I am a bug as you are on high quality color. You have helped me in that respect more than anyone else on this forum and I really appreciate that.
When you get a chance, I wonder if you could tell me:

1. What is the maximum lenghth of video you try to fit on a single DVD before you split the video into two DVDs? I have not exceeded 1 hr. on a single DVD. My menus usually contain one Play icon and one Musical Scene Selection Icon which when clicked on averages around 10-15 motion thumbnails on three pages. There is also a wav file usually playing on the main menu page.

2. What are the bitrate settings you have found which represent the cutoff point at which a noticeable degradation in video quality occurs using DVDA?

3. How are you testing? I have to color correct a loop in Vegas. Render as Mpeg 2 and AC3. Import into DVDA. Author and burn the loop onto a DVD-RW. Then test it on several sets and go back to change the color correction settings or other fillters and do it all over again. It's a PIA.

Regards,

John

Comments

Softcorps wrote on 11/5/2003, 11:05 PM

Answering question #2 will also answer question #1.

Due it the way MPEG2 works, your source footage has a lot to do with how low a bitrate you can use and not see degradation. The over-simplified explanation of how MPEG2 works is that it uses the available bitrate to encode the difference between one frame and the next. If the footage is a noise-free "talking head" video with a static background, then you can use a fairly low bitrate because there is very little change from one frame to the next. However, if your video has a lot of fast motion or video noise, where virtually every pixel changes from one frame to the next, then you will need a much higher bitrate to keep the video from degrading. There is no hard and fast rule about how much video you can put on a DVD and still keep it looking decent, it almost completely depends on the video.

James

BillyBoy wrote on 11/5/2003, 11:27 PM

1. I seem to max out around 110-115 minutes using the default render settings and about the same type of menu structure as you use.

2. I'm probably not the right person to ask... I only dropped the bitrate a few times. When I did I went as low as 6 MBPS and it didn't seem to hurt but wasn't anything special no high speed action or anything that would suffer more from too low a bitrate.

3. About all I can suggest is once you calibrate your external monitor, trust it. I explained in another thread a few months back or more where I fed a test tape through my camera playing it on my external and big screen TV at the same time with a Radio Shack amp/splitter and tweaking both sets at once to get them as close as possible.

One extra thing you may want to try is find a few seconds of a really pristine extra crisp vid ideally some closeup of a person's face so you get a nice range of skintones in natual light and then view it with the Vegas Histogram scope as its on the external monitor.

Ideally this "test image" should have nearly a flat range in the histogram scope with the peaks in the shadows, midtones and highlight areas all roughly the same height somewhere in the 45-60% range in height on the verticale scale with the midtones just a little higher then either the shadows or highighlts and peaks in both the shadows and highlight range being very close in height to each other yet a little less then the height of the midtones. You may have to hunt a bit to find such an image, if you can't locate one use the Vegas filters (mainly levels on color corrector and gamma and color curves to get there. What you're trying to do is have a really good quality good contrast image where nothing is favored.

Now lastly adjust your external monitor ever so slightly (after it was calibrated) to get the best possible looking picture of this test image and like I said just trust the settings on your monitor afterwards.

Because we both know TV's can range all over the map if you're doing work for someone else error on the side to compensate for the typical Joe Average who probably got his TV's brightness and contrast cranked up beyond what it should be.

What I'm trying to say is its easier to once really take the time to mess with your external monior as opposed to going back and forth endlessly with each project tweaking to the nth degree. Because then all you got to do is get a balanced picture on the external and everything else falls into place. Then you can use the various FX filters with confidence that what you change is going to have the effect you want.

craftech wrote on 11/6/2003, 7:12 AM

Thanks Bill,

My problem has always been that I shoot pretty much exclusively stage productions. The last one was almost completely in the dark much of the time with a spot on the singers SOMETIMES. For each singer with a spot the lighting "engineeer" varied the spot around 4-5 times per song and in most cases would flare the subject with intense white for "effect". It was probably the most difficult video I have had to color correct. For the most part I find that under typical stage ligting situations, the scopes are virtually useless . I have seen a lot of very bad commercially produced footage of stage productions as well. Stage productions are best done with 35mm film because of it's wide exposure and color saturation latitude.

The VHS tapes made from the DV master came out BETTER than the DVD (one for Act 1 and one for Act 2). The reason was because I used my Proc Amp between the DV Master deck and the VHS duplicating rack. With a few twists of the knobs I was able to get great color. There is no way to capture the master back to the computer using the Proc Amp unless you feed the signal through the analog inputs of your camera and have it transcode the signal via firewire back into the computer in which case the signal would be degraded leaving me to color correct in Vegas all over again. Some Video Cards have S-Video inputs which would work, but mine does not.

Thanks for the above as always Bill.

Regards,

John

Softcorps wrote on 11/6/2003, 10:24 AM

Wouldn't it make more sense to calibrate your TV to a known reference like color bars and then watch a bunch of commercial releases and then try to make your stuff look like that, rather than try to compensate for the "average Joe's" misadjusted TV set? Not everyone's TV is misadjusted by the same amount, so trying to make your stuff look good on their TV seems like chasing your tail.

James

craftech wrote on 11/6/2003, 11:32 AM

If you use a video calibration DVD such as the Avia Guide to Home Theater or the Discwasher Home Theater Setup Disc you will see that you have to turn down the Picture and Brightness (Contrast and Brightness) (Black and White) levels to get it correct according to NTSC standards.
Invariably both of those settings will have to be turned DOWN. You can follow the same directions on various internet sites and if they are well written they will tell you the same thing.

So now you have a "perfectly calibrated" monitor according to accepted standards and you duplicate a bunch of tapes or discs to those standards and the customers tell you that the colors are off. Why?......Because manufacturers "default" settings (even the ones where you can choose between several default settings) ALL have the black and white levels too HIGH.

You are faced with two choices. Either ballpark it somewhere in between "default" settings and the "correct" settings as BillyBoy described above or include a note with your videos that the customer has his/her TV settings wrong and they should immediately adjust them in order to watch YOUR video. With that they conclude that you don't know what you are doing.
So now you say that some of your customers don't have that complaint. That is due to the comb filters and other electronics in some sets which have a wider latitude for automatic picture control settings. Usually that will be on the more expensive sets, but not necessarily.
I test my videos on 5 different brands of TV sets before I finalize them. That is why it takes me so long to deliver them. However, the people seem to love them.
Above, you said........."watch a bunch of commercial releases ".
As I stated earlier for the work I primarily do (stage productions with "funky lighting") I have seen more BAD commercially produced videos than good ones. My budget is a fraction of Hollywood's to put it mildly. With "well lit" subject matter under normal lighting the problem is greatly reduced.

John

Softcorps wrote on 11/6/2003, 2:41 PM

I just read the "discussion" between BillyBoy and John Cline on the Vegas forum with regards to monitor calibration and I don't want to start another argument. You do it your way, I'll do it mine.

James

BillyBoy wrote on 11/6/2003, 3:26 PM

When you're passionate about a topic, you sometimes have a spirited "discussion", that's all. <wink>

Without rehashing the whole discussion as to why you should or shouldn't its important to understand WHY I said what I did. Mainly because I know a lot of people in both forums number one aren't making vids that are going to be broadcast over TV so the discussion over "legal" signal strength for example (one of the main reason why you may want a NTSC monitor for more strict calibrations) is totally mute. Number two even if you are making something for broadcast few people, I'd say probably a handful of people in these forums would know how to properly calibrate a "professional" grade NTSC monitor as a first strep which is certainly necessary which is a lot tougher then using the simpler method I offered for a regular TV and needs some pretty fancy test equipment to accomplish and you need to know how to go about it. If you just use such a monitor out of the box its next to useless because its very easy to assume its ALREADY properly calibrated which I assure you it probably isn't. Third, if you read all the things I said in the various threads that this topic has come up you'll notice I said I compared my results to that of a very expensive NTSC monitor costing several thousand dollars which I first calibrated to specs, which as I reported was more "off" of specs then my cheap little TV was.

Anyhow you're right. You and everyone else can do it which ever way they like. All I'm doing is offering a possible alternative.

Further, I can really sympathize with John since he's got one of the most demanding challenges being fussy about color and levels like I am because trying to get good color correction and levels when the range is probably very compressed due to being in a dark theater and having to deal with ever changing harsh lighting it can get really hard to balance things off. Anyway, as usual I went on too long probably.