What resolution to record in

[smelni]

Here is a quantitative question.

If you have the HVX and plan to shoot 24P in DVCproHD - is there any reason not to shoot in 1080 instead of 720?

You will have more resolution and can always downconvert.

The only reason i can think of is to increase the capacity of a P2 card or cut down on the need for many many hard drives. But from a quality standpoint - isnt the more better at the beginning of the workflow?

 

[Tzedekh]

If you have the HVX and plan to shoot 24P in DVCproHD - is there any reason not to shoot in 1080 instead of 720? . . . The only reason i can think of is to increase the capacity of a P2 card or cut down on the need for many many hard drives.

If you were shooting only 24p, then 1080 would probably be better, but if you needed a variable frame rate (other than 30p, which the HVX will be able to do as 1080p30 as well as 720p30) for display at a 24-fps rate, then you would need to shoot in 720p.

 

[mgalvan]

Well, 720p definitely has at least one major thing over 1080p ... variable framerates.

Although Panasonic hasn't stated how many, I'm sure they'll implement the ones that would allow us to create very useable slow and fast motion in a 24p timeline. This opens up a lot of creative possibilties ...

 

[USLatin]

However, if you will not need any of the frame rates that are available only when shooting 720 and you shoot it in 1080 but you knew all along that you would be downconverting to 720: then just shoot it in 720 to avoid loosing quality in the down conversion.
Sorry if stating the obvious.

Deffenitely take a look at the "720P uprez methods" thread.

 

[aryk]

I can only speculate as it isn't out yet, but I want to shoot in 720 24p. I will mostly shoot for SD TV broadcasts so I don't need that much rez. Keeping the 720p will also allow me the flexability to shoot in different framerates for speed effects and stay consistant with the look.

 

[Jim Arthurs]

However, if you will not need any of the frame rates that are available only when shooting 720 and you shoot it in 1080 but you knew all along that you would be downconverting to 720: then just shoot it in 720 to avoid loosing quality in the down conversion.

Well, some additional thoughts here... shooting in 1080 would give BETTER 720p because of the downconvert, if you stay in 1080 up until the final render out and are not delivering in DVCPRO HD (say, making a QT file for film out)...

The reason? 1920 by 1080 is really 1280 by 1080 on the original DVC codec. Downconverting to 720p (again, if not winding up on the DVC codec) will preserve ALL 1280 wide pixels giving your 720p TRUE 1280 by 720 luma resolution (with some small improvement on vertical color space as well because of the downsampling...).

Another scenario for 720p could be this... on a visual effect heavy project, shoot all the normal footage at 720p and record just the greenscreen plates on 1080 for the added boost in quality for the matte, assuming that every little bit (pun intended) counts.

Having said all that, unless I need variable frame rates I'll want 1080p most often...

Regards,

Jim Arthurs

 

[Spiff]

(with some small improvement on vertical color space as well because of the downsampling...)

I'm not sure that statement's right. I expect the interpolation from 1080p would slightly soften the vertical resolution over shooting native 720, but the extra horizontal resolution would more than make up for it. The real question is the vertical resolution of the CCDs to begin with and what role the pixel shifting, interpolation, and sampling have to do with the effective resolution.

Regardless of details, 1080p24 yeilds 80 Mbps of data. 720p24 yields 40 Mbps of data. Considering the codec is identical, I expect 1080p24 to yield better results at all resolutions.

In addition, since it's looking like the "variable framerates" will be limited to 24p, 30p, 60p and maybe 2 or 3 others, there won't be a lot of slo-mo options. Further to that, I expect 720p60 would scale well to 1080p24 if necessary.

-Spiff

 

[Jim Arthurs]

Hi Spiff...

You are right, we don't yet know how the chips produce the 1080. I was making that assumption.

However, speaking for the luma, and assuming the chips record "real" 1080 via some method; either 1080 native rez or pixel shift; I doubt a good software downsampling of the final 1080 to 720 would be in any way softer compared to just shooting in 720. I would argue it would be better, as this is a form of super-sampling.

As to the color space improvement I mentioned, I'll stand by that statement... downsampling the size of the image will always increase the apparent chroma resolution.

All of these gains would be lost, as I said, if the final product is put back into the DVC codec at 720p...

Regards.

Jim Arthurs