Comments

ByronIV wrote on 1/11/2003, 5:42 PM
If it's only photos, no. Interlaceing only really 'helps' when 2 elements are used together, one being that there is heavily fluid motion, and two, if it's going to be played back on a standard non-progressive tv and non-progressive DVD player.
harryset wrote on 1/11/2003, 9:09 PM
So. . . the next time I make a video for the gymnastics team, I should save that using interlacing.
Grazie wrote on 1/12/2003, 2:19 AM
Is there a website which has a "simple" explanation of Interlacing etc etc with advantages either way - yes?
mikkie wrote on 1/12/2003, 9:24 AM
The short answer is I think you can go either way to DVD, although you might want to keep it progressive to eliminate any quality loss from the conversion -- it might also look better on the high end systems we'll all have some day. Going to tape, you can probably keep it progressive as well, since the hardware you use to output the video stream should handle the conversion for you automatically. Not a bad idea to run a few test clips to tape and see how well your hardware handles it. At any rate, the less processing your images get, the truer to the originals the video will be.

The long answer...

You'll find I think that most template specs for DVD call for interlaced. On the other hand, if you take apart a commercially prepared movie DVD, you'll most often find the video stream is at the original 24 fps, progressive. It's my understanding that the player itself sets the output format and converts the video stream to whatever's required -- that way they don't have to create a PAL & NTSC version etc...

Going to tape however is a different story. Most TVs out there are somewhat primitive (by today's standards), interlaced, devices and feeding them a progressive video stream can cause odd things to happen with your pictures depending on the TV used to view them, as well as the pictures content.

On tape you should look for images jumping slightly up & down, look for colors that are off &/or more or less overloading the display (you'll know it when you see it) (use the safe filter in VV). You might have to add a blur to some or all of your pictures, since thin lines, especially horizontal ones can flicker or disappear from the interlacing. If you use any text, add a drop shadow completely surrounding the text for the same reason. Finally, view at least the test recordings on as many different TV's and VCR's as you can; you can have something not quite legal that'll work fine on one setup, but horribly on another, and you need to make sure your output hardware allows enough overscan so you don't have black bands on either side or the top & bottom of the screen.

DVD's are wonderful things when it comes to simplifying the setup, though you do have compatibility problems -- at least some people are not going to be able to view your burned DVDs. Tape doesn't have that problem, but there are an overwhelming number of things that you can worry about: the safe area of the screen & overscan, safe colors, some patterns will never look good, black & white levels & color space/range (all of which will be at least slightly different between the original pictures, the software, & the TV). Which is why I suggest so many times here to test your recording & hopefully you'll get lucky & won't have to worry about much of that.

For research, check out anything re: Adam Wilt for more info than most of us can handle on TV & DV specs, procedures, everything in between. Check out the forums at DV.com, especially for DVD authoring info & the compatibility problems I mentioned. If you want to explore the color range issues (virtually unlimited color range on your pics, 255 in most video software, around 235 broadcast I think), see if you can find a great article on the subject they ran a *while* back by Chris Meyer.

Gosh it'll be nice if Microsoft & Panasonic get their way & their standards are adopted... Author to winmedia, burn to disc, view anywhere on anything!
musicvid10 wrote on 1/12/2003, 12:51 PM
"Is there a website which has a "simple" explanation of Interlacing etc etc with advantages either way - yes?"

Here are two:
www.lukesvideo.com
www.100fps.com

One of the most knowledgable people in this area is Donald Graft. His tutorials for his excellent VirtualDub and Avisynth filters are ripe with information on the subject:
http://shelob.mordor.net/dgraft/
snicholshms wrote on 1/12/2003, 1:36 PM
This is interesting for me to understand.

ByronIV responded to the original question with: “Interlaceing only really 'helps' when 2 elements are used together, one being that there is heavily fluid motion, and two, if it's going to be played back on a standard non-progressive tv and non-progressive DVD player.”

harryset then said, "So. . . the next time I make a video for the gymnastics team, I should save that using interlacing."

Did I miss something here? Wouldn't you want to DE-Interlace gymnasts flying through the air? Doesn't that require checking the "Reduce Interlace Flicker" box in the video clip's properties? Same page..or am I a "few chapters behind?
Steve