720p or 1080 for digital projection? What's the best choice?

[Federico Aragon]

Hi all,

Wanted to know if there's anyone out there that has used the HVX200 for digital projection on the big screen for a film fest or similar project.

Basically I would like to learn from your experience and make the right choices to make this project look the best in the theater.

1. Details of shoot:Camera(HVX200 with P2 cards-dumping to mac), short film, day and night shots, etc. -We got all that covered-

2. Questions on shooting format:720p or 1080? 24p or 25p?

3. Post-prod workflow: Macpro - final cut (maybe use intermediate codec cineform or pro-res), some compositing, painting and/or roto work in AE, there will be no professional color grading so we'll try to nail our matrix and gamma settings as best as possible in production.

Best output for projection: motion jpg, .mov. .dpx? (Do film fests only use Barco projectors or others?)


Please answer ONLY if you've done it before, do not add tedious answers stating personal opinions on what you think would be the best.
I would like serious players answering this thread in order for all of us to benefit from their experience.

Thanks!

[Igor Ridanovic]

Hi Federico.

You should use 1080. As far as I recall HVX200 will record 1080 23.98p (24p) onto P2 media. The resolution of 1080 standard is barely lower than the projectable area of 1.85 35mm film scan. 720 on the other hand is much smaller and would not look as good projected.

If you're doing post in the U.S. make sure you use 23.98 and not 24 fps.

The best output for projection is video tape. HDCAM or D5. There are dozens of file formats and even more ways to screw the output up. It is safer to master your film on video tape although you can version it for other distribution channels and encode it to files. Which files depends on the outlet. As I mentioned, there are so many files it is hard to be ready for everything ahead of time. More often it is the distributor who will request a certain type of file to be delivered but this is rare. In most cases distributors will ask for a final color timed master and some other (audio) elements and various documents.

[Federico Aragon]

Great input Igor,

We're definitely doing post in the US. This will be a short film shot in the SD area.

As far as projection, I have not used a D5 or SR deck to project at any of my jobs (yet), but we do carry those decks for ingest, dubs and mastering purposes.

Please correct me if I'm wrong but you recommend shooting in 1080i/24p, then mastering to D5 or HDCAM tape and provide this to the projectionist? Or are you pointing out the best way to save a master of the project for any future need?


Thanks for your time and kind input.

[Brian Boyko]

I think I was reading something similar a while back.

The thing about 720p is that you give up a little bit of video quality, which might not be noticable on a projected screen, in exchange for longer recording time, less time rendering in post, and less HD space to archive.

As for 24p vs. 25p, 24p is probably the mode you want for the "film look." 30p is a clean, professional look but it doesn't look like film. 25p is similar to film but it's really most important for television broadcast in Europe and Australia - PAL countries.

And just a quick reminder:

720x480 at 60i is NTSC - compatible formats are 30p and 60i.
720x576 at 50i is PAL - compatible formats are 25p and 60i.

It is easier to convert 24p into NTSC than it is into PAL. Usually movies filmed in 24p on PAL undergo a 4% speedup to make editing simple, but that effect is noticeable.

[Igor Ridanovic]

Originally Posted by Federico Aragon

Great input Igor,
Please correct me if I'm wrong but you recommend shooting in 1080i/24p, then mastering to D5 or HDCAM tape and provide this to the projectionist? Or are you pointing out the best way to save a master of the project for any future need?
Thanks for your time and kind input.

Both. I'm suggesting mastering to one of the tape formats and using a submaster for festival viewing.

Here is just a few suggestions. Magnetic tape is a lousy archival medium. No one knows what the future holds but you can count on the fact that 30 years from now your finished HD master will be unusable. This is a whole another discussion in itself but it's good to be aware of it.

As far as the mastering format choice goes, HDCAM SR is the best if you record in 4:4:4 format, D5 is the next one and HDCAM is the weakest of the three.

4:4:4 doesn't make much sense unless your acquisition was also done in 4:4:4. D5 records in 10 bit unlike HDCAM which is 8 bit and more compressed than D5.

Still, you can achieve excellent results in HDCAM.

You wrote: "recommend shooting in 1080i/24p." Avoid interlaced standards like 1080i. If your goal is to do a theatrical release you should go progressive.

[Seun Osewa]

Obviously you should shoot the highest resolution you can afford to shoot. The HVX image is softer than other 1080p cameras in the first place.

[Dennis Schmitz]

Originally Posted by Seun Osewa

Obviously you should shoot the highest resolution you can afford to shoot. The HVX image is softer than other 1080p cameras in the first place.

The highest resolution the HVX200 offers is 960x540 (CCD wise...).
So there should be no big difference between 720p and 1080p on the HVX.

From what I've seen it seems that 720p is even better tthan 1080p on the HVX because there is some very strange stairstepping in 1080p on diagonal lines (upscaling issues?)...


regards Dennis

[Barry Green]

Originally Posted by Dennis Schmitz

The highest resolution the HVX200 offers is 960x540 (CCD wise...).

Yet this is not true. The highest resolution the HVX offers is about 1400x810 because of the spatial offset system. Each individual chip may be only 960x540, but you don't read each individual chip -- you read them all in combination, and in combination it delivers 1400x810.

So there should be no big difference between 720p and 1080p on the HVX.

And yet there is. 1080p is noticeably sharper than 720, as it should be. The HVX scans its chips into a 1920x1080 matrix, and downcoverts to the appropriate recording format.

1080P has about 20% more resolution, and is less visibly compressed, than 720p is. It just looks better all around.

From what I've seen it seems that 720p is even better tthan 1080p on the HVX because there is some very strange stairstepping in 1080p on diagonal lines (upscaling issues?)...

Don't know what you're referring to here. 1080i maybe, but not 1080p. 1080p on the HVX always looks better than 720p does.

[Chris Hurd]

Originally Posted by Barry Green

The highest resolution the HVX offers is about 1400x810 because of the spatial offset system.

Thanks Barry -- much appreciated. I try to catch this stuff myself but it's very difficult to keep up with it. I've lost count how many times I have stated on this site that the benefits of Pixel Shift are real, tangible, and highly relevant. It's difficult to comprehend how someone can look at an engine and ignore the dual overhead cams (the only analogy that comes to mind at the moment).

[Roshdi Alkadri]

hey chris, i know what settings are best used for projection. I've used the HVX on over 33 productions, so there shouldnt any reason to slaughter my posts. I do respect other people's knowledge like barry, but there's hundreds if not thousands of HVX users.

Projection: 1080p -more res, Cinelike D (dynamic range), OIS off, shutter 1/48th, sharpness -2

[Francesco Dal Bosco]

I've heard many times there is not a great difference from 720p to 1080p in the HVX video. It's a strange thing because in my HVX 1080p is far better than 720p, no doubt about it. You can easily see the difference.
I often use 720p (very good HD too) for storage and P2 space reasons but I would like to use 1080p instead. For projection purpose I think 1080 is the right choice.

[Seun Osewa]

Let's not forget that the DVCProHD codec which the HVX200 uses records 720p videos at a lower resolution (of 960x720 according to a certain website).

[Roshdi Alkadri]

you obviously want more pixels for projection, 1080p is the right choice. If you're gonna use 720p for the slowmo shots and intercut it with 1080p, you will see a difference but its not a big difference.

[Mark Donnell]

My only comment here is that I have used the HVX for over a year and have done extensive 1080i to 720p comparisons. Since I record almost everything at 60 FPS (sports events, etc) I don't have the luxury of 1080p. Although there is a very slight visible increase in sharpness at 1080i during playback, it is so slight that it doesn't offset that increased clarity of 720p when examining individual frames (versus 1080i fields). So the answer for me was 720p.

[Lee Wilson]

Originally Posted by Brian Boyko

And just a quick reminder:

720x480 at 60i is NTSC - compatible formats are 30p and 60i.
720x576 at 50i is PAL - compatible formats are 25p and 60i.

I think that should read:

720x480 at 60i is NTSC - compatible formats are 30p and 60i.
720x576 at 50i is PAL - compatible formats are 25p and 50i.