Rendering HDV for the first time, having trouble

nadia wrote on 6/22/2007, 3:54 PM
Wow, this has been a long two days of trying to figure this out and I am at a stand still. I've tried so many different ways to render this 4 minute piece and I can't seem to render a clean copy (not to mention it takes 5 + hours for a 4 minute project. yikes! is that normal?)

So here's what is happening. Every render is coming out with an interlace problem. My project HDV 1080 60i. I'm rendering it in mpg2 format. I've tried rendering it with progressive scan with good quality render. I thought I would give lower and upper field a shot too but it failed me as well. What am I doing wrong? How do I get a clean copy? What render settings should I be using?

Also, I'm still getting to know the HDV format and don't understand a few things. Why does the render automatically go to 29.97 frame rate and 15i frame rate for a 60i?

Thanks for the help!!!

Comments

nadia wrote on 6/22/2007, 6:14 PM
Alright, got it figured out! i had to do a mix and match. I set the render as upper field while the project setting is at progressive scan, and I had to go into each file and check the reduce interlace flicker. BUT... now I have one black frame that decided to jump in. Well, looks like that was a more common problem for folks than this one, gonna go read those posts about unwanted black frames dropped in.
Laurence wrote on 6/22/2007, 7:11 PM
Keep in mind that your 1080i HDV footage is only going to really look right on an HDTV played back either from the camera or an HD DVD or Bluray player. From a computer monitor you it will never really look right in this format and you will think you have all sorts of problems that you really don't have.
nadia wrote on 6/22/2007, 9:01 PM
YAY! It finally worked!!! I set my RAM preview to 0 and now there are no unwanted black frames (thanks Bob!), and the interline twitter has also left the building! Finally, a clean copy (two days later!). lol.

Thanks for your reply Laurence, I will definitely add this variable to my "what the hell went wrong" list.
Stuart Robinson wrote on 6/22/2007, 9:18 PM
>From a computer monitor you it will never really look right in this format and you will think you have all sorts of problems that you really don't have.<

HDV footage is just like any other played back on a computer, if the player understands the format it'll look fine, in my experience the above simply isn't true.
Laurence wrote on 6/23/2007, 6:37 AM
You are having better luck than me then. The closest I can come to good 1080i playback is using the NVidia PureVideo decoder. Even then I still get all sorts of interlace artifacts. It is better however than all my other experiments. Part of this probably has to do with my 21 inch monitor not having enough resolution to do the 1080 frame without scaling downwards. I have no doubt that there are PC setups where 1080i playback looks good. Mine just isn't one of them. I suspect this is the case for many other people as well.

Having said that, when I copy this same 1080i footage to a PS3 data disc or a red laser HD DVD, it looks just wonderful: much better than I would have guessed from looking at my PC monitor.
Stuart Robinson wrote on 6/23/2007, 9:43 AM
>Part of this probably has to do with my 21 inch monitor not having enough resolution to do the 1080 frame without scaling downwards.<

That's probably it, especially as you're having the best luck with the PureVideo engine as it is known for its quality of scaling (up and down), in fact NVidia have some impressive clips to demo that.

I would imagine that trying to fit 1080 into a smaller screen area is going to look even worse if the clip is interlaced. My experience is much better than yours, perhaps due to the 24" Dell I've been using with my HDV clips.

Incidentally, I've been thinking for a while that shooting 25 or 25p HDV produces more MPEG artefacts in the source than shooting 50 or 60i, but that's not a scientific conclusion, just a casual observation.
Laurence wrote on 6/23/2007, 9:55 AM
I did a few jobs with Cineframe 30 but have now stopped using it. For one thing, autofocus is twice as slow with Cineframe 30. The judder drives me nuts as well. Also I like being able to add slow motion effects and you need the faster frame rate to do that. I haven't noticed more mpeg artifacts in that mode though.
4eyes wrote on 6/23/2007, 1:19 PM
da