Thanks for the responses. The DVD isn't the issue, it worked in another DVD player and TV when we watched it earlier this week. It can from a TV station (WTVG) too, so I trust their work. I haven't tried another DVD player with the
system, but my guess is that it was something in the
processor. We had never had this problem before though.
I would like some more details on this. There is also an option to bypass the highres on the output. I don't think I tried this yet.
Well, I am not too sure why you haven't noticed it before. Unless something is really going bad, it should have been there any time you use the
switcher and it has to upscale the signal. By upscaling, I mean it is taking the
NTSC analog
composite video or component (Y/C or R-Y,B-Y,Y) and converting the approximately 720x480 (I said approximate don't no one go getting all picky or I'll have to start a new thread on resolutions) and upscaling it to 1024x768 which is the popular
projector standard. It *may* also be converting the scan rate and other voodoo for you as well. One thing you can do is set your output scan rate to 60hz as this is the closest to
NTSC video. If you are running the
projector at 70hz or some other freq, you can see where the
scaler is doing more work then it probably needs to do.
If you are playing back from a computer or other hires source, then it does not have to be upscaled and is passed right to the output (as quoted from the company's website). So, in a nutshell, anything that is not whatever the native output resolution of the
switcher/
scaler will have to bescaled / converted.
Also, the other poster is right that
DLP's insert a
bit of the delay due to the way they work. Another thing is that you *can* put delays on the mic lines provided all of the stars and planets align and you are in the perfect situation. I wouldn't count on this 99.9% of the time though cause it is pretty dang ugly for the person having to do the speaking. I am hoping that as processing speeds of the scalers get faster and we move over to HD sources that require less horsepower to process, this issue will fix itself.
Most of the time, unless there is something like a talking head in the video, most people will never notice it.
So, here are a few options:
Put an audio delay on the source (DVD, VHS, DVCAM, whatever is not native 1024x768
RGBHV).
Convert your media to some sort of video file and
play back from the computer. Test this first because now the computer is having to do the upscaling and they don't always look good. Remember you are taking a 720x480ish signal and bumping it up to 1024x768. To keep it looking the best, it needs to be played back at it's native resolution. For example, if you have some miniDV footage, then it will
play back at 720x480 which as you can tell is not "full
screen" (1024x768). You can set some players so that they
play in a window or you can embed it into something like
power point. Another thing that puts a hit on quality is
image compression. I find that a video from a DVD (MPEG2) looks horrible after the compressed
image gets processed yet again in the
scaler on it's way to 1024x768. Again, quality varies with the quality of the encode but just like audio, encode->decode->re-encode doesn't work so well. True, most of your digital formats such as miniDV are compressed but not as bad as DVD.
Check to see if the devices you are using can be gen-locked. This helps by bringing everything into time and you might makeup a few ms of time. I do this whenever possible because I can then
switch sources in pip windows without them going to black in between to resync. This won't be possible with a consumer DVD player and I don't know if they even make a genlockable DVD player.
As far as media goes, my preferences are in the following order DVCAM, BETA-SP (cause the machines are tanks),DVCPRO. I try to steer the clients away from DVD whenever possible.
Now, if you are working with HD sources and HDSDI signals, this is a totally different story. Most of those native resolutions are well above the 1024x768 and you are actually scaling down the video. Of course if you have HD video to work with in the first place, then you most likely will be using HD switchers and projectors as well.
Hope this helped you out and didn't confuse the issue.
kw