We have put together a video of a high school theater musical and we've noticed on the scenes where it is low light or a spotlighted subject. The darker area around the spotlight seems real grainey. But it seems like it is mainly when I play it on our DLP lcd tv not the standard TV. Any one have an experience with this. This is not the first time we've seen this. But it's always on low light. We have the exposure turned up on the camera to compensate for the low light.

Can't say for sure but my guess would be poor quality analog to digital conversion in the DLP device from the analog output of the DVD player to the screen. Many HDV digital TV's do a pretty poor job with analog video in.

Hate to say this, but using auto gain, or high gain levels on DV cameras or worse yet HDV cameras generates really nasty noise. There are some
de noiser apps out there to try to "clip" some of this.
When the mpeg encoder goes to work, it can't really tell what is noise and what is picture detail, so even more unwanted "artifacts" are added.
Now try up-scalling this result at least 3x. Add to that the fact that some HDTV handle SD very poorly.


There are some external mpeg encoders like TmpGe Source creator that have some filters included which can improve some low light grain and noise.
They work, but do not expect miracles.

Next time try to improve the lighting, or mabe rent a three chip camera with at least 1/3" chips.

LCD TV's often have problems with the colour black. So if you only see this with LCD tv’s this could be a cause. Look at the contrast ratio of the television. The higher the number, how better they can handle it. (the contrast ration actually tell you how many steps between white and black the screen can handle)

Another cause could be that the colour depth is removed due to the encoding.

I just reburned a copy of the project using the highest quality possible on Avid that would allow  it to fit on one disc.  I got to thinking.  When we recorded the play, we used Panasonic Super MiniDV 80 minute tapes.  They are designed for 3ccd cameras.  The question is,  we recorded in LP so we could get the 2 hours worth of use out of the tape to prevent running out of tape during the production.  Can recording in LP instead of SP  have that big of a difference in the quality of the outcome.  We normally record in LP to take advantage of the longer tape,  but most of our projects have had better lighting because they were for Hockey.  This would really be the first time we recorded something of this nature.  I did notice the difference in the picture when playing the dvd on a SD tv than on the HDTV.  Also I saw a difference playing it on 2 different dvd players.  Both dvd players were Standard Def.  I'm just baffled that it would look outstanding if I played the same dvd on the computer using the dvd player program,  but would look different on another tv.  I wish Dual layer disks were cheaper. 

We shot the play using a Canon GL2 and an XL1.  The Lighting we had no control of because it was the lighting of the auditorium that we shot in.  As for the exposure,  The exposures we set manually. 

In DV, there is no difference in picture quality in SP vs LP:the same bits are recorded on tape, it's just that the bit density is higher (and the risk of frame corruption also), at the expense of reliability & readability of the tape on camcorders other than the one that was used to shoot.

I've always wondered about this. Technically, BenoitM is correct. However, if you compare DVCAM (which is really the same as DV but at an even higher density) to DV and then to DV at LP, there is a difference. There shouldn't be, but there is.
 

Doesn't DVcam record at a faster tape spin rate? Could that account for the higher quality achieved?...........Edd

The head and tape speeds are different, but the data is the same. To the point that all Sony DV camcorders (or at least the miniDV ones) issued since the development of DVCAM and play back DVCAM tapes.