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View Full Version : What resolution/mode to shoot?


Wheatloaf
07-07-2006, 02:32 PM
Hi everyone,

It's getting close to that exciting time where we choose the camera settings and shoot some test/previs. You'll have to excuse me if I need a lot of handholding at this stage. As I know more about the camera the the career I will hopefully contribute useful posts instead of always asking questions!

The director of this feature was intially assuming we'd shoot 1080, because I think in his mind that's what HD is. I was reluctant to add that much to our budget in that area (HDD space, renting additional cards) as I don't expect to see a film out for this movie... it's likely more of a festival and DVD type film. With this output in mind, how much am I really losing by going 720? What are the benifits of 1080?

If I do shoot 720, what is the best mode? Since we are probably doing DVD out, would 24p (which is the 24p inside the 30i signal, right?) be the best mode?

In the other thread about framerates, GeoMar said:
"One thing I like about 24Pn is that if you are making a DVD you can encode it as 24 fps and let the DVD player do the pulldown. With fewer frames to encode, you get more bandwidth per frame, which is cleaner compression. It's like getting free bandwidth."

Am I to understand that if I shoot 24pn there is no trouble outputting to DVD? No compatibility issues? And further, it looks great?

Besides the aesthetic difference, are there any technical limitations to mixing 24pn and other framerates like 26 or 28? I am giving each set of characters different looks, and one of the sets has kind of a surreal feel to it, and I'm wondering if 26fps might be a subtle way to bring that out, but I don't want to create post nightmares.

I also want to double check with you guys on the storage... 1080i/24p is 1min/1gb. 720/24pn is 4min/1GB, is that right? How much is 720/24p 720/24pa and 720/26p?

I hope these questions aren't too retarded. I tried to search, but I can't find any of it.

Thanks so much for your help!

Barry_Green
07-07-2006, 02:59 PM
720p is every bit as much "HD" as 1080i is. The only people who say otherwise either a) don't know what they're talking about; b) don't recognize that the entire European Broadcasters Union rejected interlace in general, and 1080i in particular, and endorsed 720/50p for the EBU, or c) work for Sony (whose new marketing slogan on their interlaced 1080i stuff is "True HD", despite the professional standards body of entire continents like Europe and Australia thumbing their noses at interlaced).

With that said, 1080/24p is higher definition than 720/24p is. At equivalent frame rates, the 1080 signal retains more definition. 720/60p has less spatial but more temporal resolution than 1080/60i, but at the same frame rate (720/24p vs. 1080/24p), 1080 is better.

If you're shooting to the cards, 720/24pN will give you 2.5x as much recording time on the card as 1080/24p will. In that context, 720/24pN is quite attractive. And the resolution loss is not *that* drastic; 1080/24p retains about 20% more resolution overall than 720/24pN does. So if you want the best image possible for an HD master, I'd say shoot 1080/24p if you can work with the recording time limits. If recording time is paramount, 720/24pN gives you 2.5 times as much recording time, for only a small penalty in ultimate resolution.

And yes you can make a 24p DVD from 720/24pN or 1080/24pA or 480/24pA, they all work very well. Remember that DVDs are standard-def only, so whether you shot 720 or 1080 or DVCPRO50 480/24pA, it'll all look basically the same on the DVD. The difference comes in if you want to make a high-def version of your production; that's when you would have wanted to shoot in HD in the first place.

For recording times, 1080 is 1 minute per gig. 720pN mode takes up a proportional amount of space based on what the frame rate is, so 720/60p is 1 minute per gig, 720/30p is 2 minutes per gig, etc.

Jim Carswell
07-07-2006, 03:11 PM
Hey Barry,
Just out of curiosity... what do you typically shoot? 720? 1080?

Also any chance of getting an HVX bootcamp event in Atlanta, Jacksonville, Charleston or Savannah?

Jim

araujofh
07-07-2006, 06:03 PM
Is there really much difference between 720p and 1080p on the HVX?

Would a film out from 720p vs 1080p be that noticeable?

JesterJJZ
07-07-2006, 06:43 PM
I tend to shoot 720p cause I use lot's of speed effects. I would sometimes shoot a shot in 1080p if I'm doing a composite. It gives me more to play with and looks better when downrezed to 720p.

Barry_Green
07-08-2006, 06:25 AM
Hey Barry,
Just out of curiosity... what do you typically shoot? 720? 1080?
I shoot 1080 whenever I have the option. It just retains a bit more resolution, about 20% more. 720 looks fine, and given that 720/24pN gives you 2.5 times as much recording time on the cards, well, that's hard to argue with. But I prefer 1080/24p whenever possible.

Also any chance of getting an HVX bootcamp event in Atlanta, Jacksonville, Charleston or Savannah?
No plans for any of those; I wouldn't mind doing Atlanta (since it's one of the four cities that my new airport flies directly to) but it's all up to however many will sign up, and if it makes sense to fly everyone across country to do it.

Barry_Green
07-08-2006, 06:27 AM
Is there really much difference between 720p and 1080p on the HVX?
About 20% more resolution, mostly horizontal but a little vertical too.

Would a film out from 720p vs 1080p be that noticeable?
The jump from standard-def to 720 is far more than the jump from 720 to 1080. From SD to 720 is night and day; from 720/24p to 1080/24p is like night and pre-dawn. It's a little different but not that much.

Now, with that said, remember that NTSC users used to think that shooting in PAL gave them higher res for a filmout, and PAL is 20% higher res than NTSC, so yes it may make a difference. But the big, big difference is made in shooting in HD instead of SD in the first place.

Wheatloaf
07-08-2006, 03:08 PM
Thank you very much for your detailed response.

It sounds like if I only have DVD out in mind that I can shoot 720 and be fine.

Realistically how far are we from being able to author our own BluRay or HDDVD DVDs? Should I even bother worrying about that? As I see it, a film out or BluRay/HDDVD are the only reasons I would have for retaining that extra 20%.

I still wonder if I will have issues mixing 24pN and other framerates on the same FCP timeline. I love the space saving of 24pN (the on the day implications of having more recording time are signficant for me), but it may need to jive with 26fps stuff in the same timeline.

Is there anything special you have to do in FCP for DVD out of 24pN or 24pA or 26fps or anything? The only reason I ask is because it was an issue specifically brought up by the director. Unfortunately post is like my kryponite so I was unable to respond in a detailed way. I suppose when we shoot our test footage he will be able to do a DVD out on his own and see how easy it is... is that a good plan?

Thanks Barry, et al. The hours of post reading I do here are always so informative!

Ryan Patrick O'Hara
07-08-2006, 07:06 PM
Hey Jim where are you from?
Count me in if you decide on a GA bootcamp.

Jim Carswell
07-08-2006, 07:18 PM
=Prodigy=
Thanks for your interest in a Georgia bootcamp. I'm in Savannah... but am willing to travel to Atlanta, Jacksonville, Charleston or even Tampa if needed for a bootcamp. How about you?

I just looked at your profile. Are you attending SCAD?
Jim

Ryan Patrick O'Hara
07-08-2006, 08:00 PM
Yes, I will be a third year film and television major. Very cool to find another Savannah HVXer!! How about you?

Jim Carswell
07-09-2006, 05:30 AM
I'm not one yet. Waiting for it to arrive. Looking forward to it :) . How long have you had yours? What sort of work are you doing with it?
Jim

Wheatloaf
07-10-2006, 06:38 AM
I still wonder if I will have issues mixing 24pN and other framerates on the same FCP timeline. I love the space saving of 24pN (the on the day implications of having more recording time are signficant for me), but it may need to jive with 26fps stuff in the same timeline.
This question still irks me. I won't be able to test it because the editor has different hardware and software than myself. We will definitely do a camera test, but I'd rather know sooner than later, as it affects some of my conceptual planning (my HVX arrives only a week ahead of day 1).

If anyone has experience with mixing framerates, I'd love to hear it!

Thanks!