HVX discussed in ASC magazine

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October's issue has an article under "Short Takes" about the music video for Switchfoot's "Awakening." The music video was shot in 720pN and then upconverted to 1080p for mastering. Here's an excerpt with a quote from the article by Michael Cioni of Plaster City Digital Post, Hollywood.

- Since completing "Awakening," Cioni recommends that cinematographers using the HVX200 record using the camera's internally upconverted 1080i format. "At first, everybody thought shooting at 1280x720 would be better because that's closer to the native resolution of the camera," explains Cioni. "With the HVX, in every frame you can actually see the compression - particularly in low light - and so you're scaling that compression 33 percent when you up-rez to the 1080 master. The compression at 1920x1080 is less visible because even at 1080, you have the same amount of compression you have in the 720 image. The downside is you have to record 1080i, and your card economy also tanks about 40 percent." -

This seems to contradict what I've heard about recording in 1080i. Any thoughts/explanations?
 
Wrong reasoning, but right results. I've been saying for two years now -- if you want the best results, shoot 1080.

Saying the 1080 is "internally upconverted" is just plain dead wrong. Saying 720 is closer to "the native resolution of the camera" is also dead wrong -- the native resolution of the camera is 2K. 720p is made from downscaling the internal 1920x1080 signal. So why not record the 1080 directly, instead of a downrezzed-to-720 signal? I mean, it's a common misconception, but it's still a misconception. The camera delivers a 1920x1080 signal from its chips to its DSP -- and Juan Pertierra says that it's actually capable of even more, it's capable of a 2K signal. So use that.

Furthermore, his observation on compression is right, but not as far as it should go. It's true that if you blew up a 720 image to the same size as a 1080 image, you'd see more compression artifacts because they would be optically magnified during the blow-up process. But it's more than that -- the 1080 is physically less compressed in the first place.

So again, for the best results, especially for blow-up, use 1080/24pA (not 1080i, heavens no). The only reason to use 720/24pN would be if you needed the space savings offered by that mode, or if you needed slow/fast mo, or if you're cutting on Avid which doesn't support pulldown removal. But as far as image, 1080/24pA is better than 720/24p.
 
Barry_Green said:
the native resolution of the camera is 2K. 720p is made from downscaling the internal 1920x1080 signal. .
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With all due respect Barry, since I owned the HVX200 as well; I must disagree with that statement. The HVX200's core head is not true 2k and no where near it.

Simple, just cause I have 8mm film scanned at 4k or even 2k doesn't all of a sudden turn my 8mm footage into 2k or 4k. It's still 8mm worth of detail, and no more or no less.

I do agree, that 1080 is the best mode to film with on the HVX200, and from there down convert to 720p if needed.

Just my two cents of reality IMHO......



Michael Pappas
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PappasArts said:
With all due respect Barry, since I owned the HVX200 as well; I must disagree with that statement. The HVX200's core head is not true 2k and no where near it.
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And yet that's the image that Juan of Reel-stream says he gets out of it. And you saw what he got from a standard-def DVX; or, i fyou haven't, you should check it out again. He gets sharper higher-res pictures from a DVX than most of the competing HD models. I have no doubt he'll get a legitimate genuine 2K out of the HVX with the Hydra.

Simple, just cause I have 8mm film scanned at 4k or even 2k doesn't all of a sudden turn my 8mm footage into 2k or 4k. It's still 8mm worth of detail, and no more or no less.
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That statement is true, obviously. But that's not what we're talking about here. There are people spreading the misinformation that the HVX is a "standard-def imager that up-resses to HD", or that it's a 720p camera that upresses to 1080. Those statements are completely inaccurate and do a great disservice to the users, as the interviewee of that article found out.

There is more detail in the 2K image of the Hydra than there is in the 1080p recording. There is more detail in the 1080p recording than there is in a 720p recording. Any conclusion other than that the HVX is delivering a true native resolution (and not up-rezzing) is just illogical as well as wrong.
 
Barry - I believe this 100% - but why the heck to people (esp. on another major board) still buy into this BS? Some of these are really smart people as well.

I wish Panny would write something officially so I could post a link to it everytime I hear that standard def line.
 
taormina said:
.........but why the heck to people (esp. on another major board) still buy into this BS? Some of these are really smart people as well.

I wish Panny would write something officially so I could post a link to it everytime I hear that standard def line.
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I've linked before to a document written by Panasonic themselves, and being 'official' has to be provable if challenged, see ftp://ftp.panasonic.com/pub/Panasonic/Drivers/PBTS/papers/AG-HVX200.CCD-WP.pdf .

It states fairly categorically that pixel shfting increases resolution by a factor of 1.5x if the lens is up to it, compared to native chip resolutions, and quotes that "up to" 1440x810 may be derived from the HVX200s chip set. With the caveat "Certainly this is a theoretical “best case scenario”........." (which I take to mean that by 1440 the mtf will have declined to zero) Other references I've seen put the figure at more like 1.3-1.4x - certainly I've not seen anything substantive to claim 2x.

It also gives a good analysis of their reasoning of designing the front end of the camera as they did, what they considered to be the best compromise set, which I for one find fairly convincing.

Will Hydra acheive 2k resolution? It certainly seems to me like perpetual motion is promised at the moment, but let's see what emerges. I have no doubt that it will be better than the cameras native recording, but true 2k? A 2k recording, undoubtably, but if it manages true 2k RESOLUTION within that it will rewrite Panasonics own rule book. In the meantime I'm minded to agree with Michael Pappas's comments about 2k scanning 8mm film.

But show me a test chart from Hydra showing true 2k resolution, and a zone plate showing it's not aliasing, and I shall be the first to sing it's praises. The most limiting factor with the DVX100 was the DV recording (esp for NTSC) which was fairly easy for Andromeda to overcome. With DVCProHD recording in camera, we have a very different scenario here.
 
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Anyhow:

Trust yur eyes.

I have never really understood where the crap comes in:

1. Pixelshift
2. Codec

But I tend to blame the codec as time goes by.

In studio we are now using the (seemingly irrational) workflow of recording through component to aja to prores.

There are catches... (component)

But there are clear gains as to noise and color

First thing I did when getting the cam was some quick a/b 720 vs 1080

1080 looks better...

Then I did some SD-out tests

1080 source looks better...

Can I elaborate?
Not really!
I'd take the Varicams 720 (with the Varicam dialect of the codec) any day.

But on the HVX, 1080 just looks better. To me.

Thus I NEVER shoot 720 if I don't need vfr.
(which I pretty regularily don't need...)

Gunleik
 
Look 1st said:
just like they did with Andromeda.
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Maybe I should add "and the laws of physics" to "the Panasonic rule book" .......... :)

I don't want to be seen as decrying Andromeda as such - I do think it will provide an improvement over an unmodded camera, but strongly suspect the advantages will be far more to do with dynamic range, much less resolution. What it could do though is provide the resolution that the HVX manages in 1080p mode at 60fps, and not just limited to 24.

Taormina asked for a link to a Panasonic reference about the technicalities of all this, to use to rebut "that standard def line". I've provided that - clearly it shouldn't be seen as a standard def camera - but the same White Paper holds no hope of true 2k resolution from this chipset, even if a 2k stream is output.
 
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Interesting point you raise Michael, "more to do with dynamic range", coupled with minus the compression that Hydra will provide. Can't deny, 2k from a 1/3" CCD is unique. 1/3" CCD known to be more noisy than larger chips, or is that more to do with compression, or a combo of both? Cardmaverick mentioned in other threads, that the HVX has smaller photosites than the DVX (same size chip), and this may pertain to resolution or noise (not sure on that)?

I tend to follow Gunleik, and trust my eyes. Not looking to take side here, very interesting discussion.

I am still banking on Hydra to give me a cost effective Viper/RED camera (saying "cost effective Viper/RED camera" may stir some debate! emphasis is "cost effective"), coupled with a 35mm adapter and cine glass. :D
 
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I'm just curious. What exactly are all you people doing with this 2k or even 1080p footage? What is the market for it? Do you guys all shoot theatrical stuff or burn out to film? If so what type of stuff? Anything I could go see and check out this 2k look? Or do you just want to shoot 2k then downrez it back to 1080i or 720p or SD for mass audience viewing? Does the 2k image really look that much better broadcast at 1080i and compressed by the broadcaster and then again by the DVR?

The reason ask is because the workflow for HVX200 720pn is so much easier than that of 1080pn and or 2k it's kinda hard to give up. But if the image is that heads and shoulders "holy smoke what did you shoot that on?" better. I'd consider it.

If all this 2k vs. 1080p vs. 720p vs. he said she said chip size business is just theoretical discussion for the fun of the forum that's cool but I would like to know.

I mean the switchfoot video is most likely going to be seen on Youtube by it's largest audience it's next audience is going to come from MTV. FUSE or the other cable companies. So what was the point of uprezing it to 1080p? Nobody is broadcasting that are they?

What am I missing here? I feel like I'm getting behind the curve on this one. So again I ask what are you guys shooting and where is it being seen?

Thanks!
 
I believe that no matter what your distribution format, you should always start off recording in the best possible format. (Also think about future-proofing)

After seeing what Chris is getting out of his Andromeda DVX, I believe that 2k from a Hydra HVX would look phenomenal if captured right. Following Chris' examples (assuming the basics hold true for the HVX) a 2k down-sampled to 1080p image would beat the pants of a lot of cameras, most costing several times the amount of the HVX.
 
Also, it is not just the 2k factor. Bypassing the DVCProHD codec means no compression and recording up to a 4:4:4 14-bit linear RGB signal, not the compressed encoded 8-bit 4:2:2 signal we get on our P2 cards, which is not bad, depending on your intended use. 14-bit, that is a lot of colors and grayscale steps. For the most part, I foreshadow recording from Hydra a 10-bit RGB via a record LUT will suffice for my use. Intended use, make Features that are in the works. Release from HD-DVD/B-Ray to DVD, etc. Film out not likely, however, intend to have a 2k or 1080p24 4:4:4 and/or a 4:2:2 master in CineForm codec.

Record size (up to 2k), bit rate (up to 14-bit) and uncompressed or lossless 4:4:4 signal, and cost effective. Yes please. :smile:
 
holditnowfilms said:
I'm just curious. What exactly are all you people doing with this 2k or even 1080p footage? What is the market for it?
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Less than a year ago I posted that the first "Full HD" or "True HD" (marketing speak for 1920x1080 res screens) were being seen in the shops, and with Blu-Ray/HD-DVD releases being predominantly 1080p the future must be a 1080 one.

In the next few days I shall be getting a flat screen for home use (a Panasonic plasma, incidentally) and looking round for that the impression is overwhelmingly of how many more - the majority maybe - of screens on the home market are 1920x1080, and the trend is expected to continue.
William_Robinette said:
After seeing what Chris is getting out of his Andromeda DVX, I believe that 2k from a Hydra HVX would look phenomenal............ assuming the basics hold true for the HVX..........
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The basics may hold true for dynamic range, but not necessarily for resolution. The basic DVX was most limited here by the recording medium - DV, and esp for NTSC - and far less the chip set, so bypassing the DV recording was an obvious way of getting substantially more performance.

But the HVX uses DVCProHD, not DV, so the same basics don't apply, and theory seems to suggest that the codec and chipset are much more closely matched now than they were with the DVX. Hence, a comparable resolution boost is unlikely.

Dynamic range and compression are different matters, and bypassing the 8 bit depth and compression of DVCProHD may give worthwhile benefits in post.
 
harddrive said:
But the HVX uses DVCProHD, not DV, so the same basics don't apply, and theory seems to suggest that the codec and chipset are much more closely matched now than they were with the DVX. Hence, a comparable resolution boost is unlikely.
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I was talking about dynamic range and noise. But still, I believe they will get more resolution out of the HVX. I agree that the jump from 1080p to 2k isn't nearly as large as 480p to 930p (Andromeda's spec I believe?) but I'll take it. The uncompressed feature is the most attractive, resolution matters less to me.

Still, the DVX is listed as having a 410,000 pixel chip set. The Andromeda increases that to the neighborhood of 1,425,000. Imagine what they can do with a 2,000,000ish chip set for a base.
 
William_Robinette said:
I was talking about dynamic range and noise. But still, I believe they will get more resolution out of the HVX. I agree that the jump from 1080p to 2k isn't nearly as large as 480p to 930p (Andromeda's spec I believe?) ..........

Still, the DVX is listed as having a 410,000 pixel chip set. The Andromeda increases that to the neighborhood of 1,425,000. Imagine what they can do with a 2,000,000ish chip set for a base.
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There are three very distinct issues which are getting badly blurred here:

1 Actual nos of pixels on chips
2 "Derived" resolution from the above
3 No of pixels recorded

1 and 3 are pretty obvious, and can be assigned exact numeric values. 2 is much more nebulous, largely due to the fact that resolution normally "tails away", and the figure you assign to it depends on to what extent you allow it to tail off. Panasonic refer to 1.5x the pixel count for a pixel shifted technique as the absolute limit, others refer to 1.3-1.4x as the figure where you've lost resolution for practical purposes. They are both correct, depending what you're interested in.

But even using the best figure (1.5) Panasonic say that you can't get any true resolution out of this chipset above 1440x810, and I'm sure would argue that therefore it and the DVCProHD codec at 1080p (with 1280 horizontal pixel recording resolution, not 1920) are a good match. And I'd agree.

And it doesn't matter how much you upscale the recording resolution - we're back to Michael Pappas point about scanning 8mm film at 2 and 4k resolutions. What's the point, the film is the limiting factor, not the recording format? All you're doing is increasing the data rate for no visible benefit.
The uncompressed feature is the most attractive, resolution matters less to me.
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Which is exactly where Hydra may be of practical benefit, I agree.
 
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