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VIPER and HVX-200. Cutting footage together.


Michael Totten
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Hi-

 

I just wrapped a short film using the Viper as the "A" camera and the HVX as the POV camera. On the Viper, I shot uncompressed 4:4:4 at 440 megabits to an HDCAM-SR deck in the 2:37 aspect ratio. We shot 1080p 23.98.

 

On the HVX, we shot 1080p 24/ 16:9, so I guess we'll have to crop and zoom to match the Vipers aspect ratio and I know we'll loose some resolution as a result. Before our online edit and color correct we'll convert all HVX footage to HDCAM-SR so I think that'll help with big with matching the cameras/colors.

 

My question is has anyone had any experience cutting footage from these two cameras together? If so, I'd like to here about your experience. Please send me a private message.

 

Best,

Michael

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Actually, Michael, I think you are the 1st in the world to ever use that combination.

 

It seems you have just completed the first project using pro HD cameras that are at the extreme opposites on the scale of resolution. *smile*

 

With Viper probably being the best in resolution and the HVX200 probably being the worst in resolution, we are anxiously awaiting your finished outcome. Please document your workflow process and report back to us.

 

If it all works out and looks great, you may have just demystified the measurebator talk on "what camera is best" for this or that!

 

*smile*

Edited by Mr. Shannon W. Rawls
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Hi-

 

I just wrapped a short film using the Viper as the "A" camera and the HVX as the POV camera. On the Viper, I shot uncompressed 4:4:4 at 440 megabits to an HDCAM-SR deck in the 2:37 aspect ratio. We shot 1080p 23.98.

 

On the HVX, we shot 1080p 24/ 16:9, so I guess we'll have to crop and zoom to match the Vipers aspect ratio and I know we'll loose some resolution as a result. Before our online edit and color correct we'll convert all HVX footage to HDCAM-SR so I think that'll help with big with matching the cameras/colors.

 

My question is has anyone had any experience cutting footage from these two cameras together? If so, I'd like to here about your experience. Please send me a private message.

 

Best,

Michael

 

 

Like Mr. Rawls said, those cameras are pretty opposite in every way. I think your best bet, since the HVX was used for some sort of POV, is to make the POVs look distinctly different than the rest of the footage. Trying to amke the two cut seamlessly will probably work about as well as mixing film and HD cams worked for Miami Vice...

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Like Mr. Rawls said, those cameras are pretty opposite in every way. I think your best bet, since the HVX was used for some sort of POV, is to make the POVs look distinctly different than the rest of the footage. Trying to amke the two cut seamlessly will probably work about as well as mixing film and HD cams worked for Miami Vice...

 

 

Yeah, I'm NOT trying to "match" the two cameras in anyway other than aspect ratio and color. The POV is going to be it's own unique type footage that will serve the story well. The point of view is coming from a man buried up to his waste in a desert dry lake bed. So he is really close to death.... his point of view is a little "off".

 

Here is a link to some set pics that someone snapped off.

 

http://homepage.mac.com/michaeltotten/SCORP%20/

 

I'll post some actual footage in the next couple days.

 

cheers,

Michael

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  • 1 year later...
What an awesome location. You lucky summamariches!!! *smile*

 

I pray it turns out well, that you entertain many and that you guys make millions and millions of dollars on this project. Good luck!

 

This is probably old news now, but Cloverfield did the exact same thing, shooting viper alongside HVX.

 

just an FYI

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  • 3 weeks later...
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The HVX200 doesn't shoot 1080p, many people I talk to recommend that you shoot in 720p on this camera, because it is the native resolution of the chips.

Actually not. The chips are 960 x 540. So both 1080p and 720p are upconversions. There are also strong proponents here of the 1080p upconversion. It should be easy to test both and pick the one that looks best at the far end of your workflow. Bear in mind the f/4 diffraction limit on 1/3" chips.

 

 

 

-- J.S.

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  • 6 months later...

You guys are all wrong. The hvx200 does not upprezz to 720p.

 

The green sensor is offset by 1 half a pixel, and the DSP uses pixel shift to resolve about 20 percent more detail than true 720p.

 

I know that from doing charts with the SDI out. The camera does truly resolve halfway between 720p and 1080p.

 

But then DVCRO Hd takes over and cuts the resolution again and makes the pixels non square..

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You guys are all wrong. The hvx200 does not upprezz to 720p.

 

The green sensor is offset by 1 half a pixel, and the DSP uses pixel shift to resolve about 20 percent more detail than true 720p.

 

I know that from doing charts with the SDI out. The camera does truly resolve halfway between 720p and 1080p.

 

But then DVCRO Hd takes over and cuts the resolution again and makes the pixels non square..

 

Hi,

 

As John said The chips are 960 x 540. The HVX is a very average camera.

 

All your charts show is that recording at 1080 produces more resoloution that at 720p, that does not say that the resoloution is more than 720p. If you looked at the output of a Viper next to the HVX you would realise that you are being tricked.

 

Stephen

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The hvx is a good camera. The viper is a better camera. So what?

 

The camera is not a one trick pony in the eyes of the thousands of indie filmmakers using it.

 

The camera resolves somewhere around 1400 horizontal lines.

 

We had a few fanboys when it was released, some of whom bought Red Ones as their careers had not been revolutionized.

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Why do we have go around labeling people as fanboys here? It just perpetuates the rediculous "my camera is better than yours" mantra. It's not needed.

 

If one person argues the respective benefits of one format or camera, and another person disagrees, does that make the former a fanboy?

 

It's a wild world full of formats, codecs, sensor types, compression types, pixel counts, ect

 

There will be a ton of opinions.

 

I think, if you can create art with your instrument (camera in this case) than that's what matters.

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  • 2 weeks later...
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Interesting.

What's an explanation behind this?

 

 

Light enters your lens as a wave. As these waves spread out, particles of light that pass through the center of the lens hit the center of the target faster than those diffracted more by the lens. Basically, any lens has a bright spot in the middle and everything else that comes through it does so at more of an angle so it takes a bit more to get there due to diffraction. Aim light through even the most perfect of lens and you will see it makes 'rings of light' on the other side as the light hits the target at some point. Look up Airy Pattern on the web to see a definition of this and you've found the core of the problem with small chips and a small iris'. As these waves hit the pixels in a chip you get overlapping of brights and darks due to the small individual target areas and the 'edges' of the waves of light. These areas that overlap (light and dark) end up canceling each other out making grey and cause you to lose sharpness of the image being projected through the lens. Technically it’s about contrast loss due to diffraction. The larger the targets on your chip, the more they get the good light and the less they get the overlaps of 'bad' light and hence loss of sharpness. On the other end of the equation, the higher the f-stop number the more you create bigger gray areas in those “rings” cause you are letting less of a wave through making more areas of light and dark after diffraction. On top of that different frequencies of light all have different timings in terms of the Airy Pattern created. In other words you have a rainbow of colors all trying to make their way into your CCD pixel. Add all sorts of coatings to lenses to try to alleviate this and you have the difference between better quality lenses and those things with the name ‘Leica’ printed on them that are found on cheap cameras. But even the best of the best lens has a physical limit to focusing light properly and it’s the iris that then becomes your worst enemy. See, there actually is a reason some lenses are $100k each. But money can’t buy love and eventually all lenses suffer the same fate, just some faster than others. The more you close down the iris the less light enters and the more your contrast drops. When it hits zero, you now have lost resolution. Every lens has a diffraction limit. Since it’s all-mathematical, known expressions for what percentage of contrast you have are known by the size of the target you have and the F-stop of the lens. It’s part of a big complicated equation called Modulation Transfer Function (MTF). On a chart that shows how much contrast ratio light gives you through a lens, the graph looks like a diagonal line for the most part in the center and curves off at the top and bottom. So for a camera like a 2/3 inch F900 you’d be at about 70% contrast at f4 meaning you haven’t hit the limit of measurable contrast (sharpness is still possible), but you are already close to making a worse picture than if you were wider on the lens. At about f13 on a F900 you are at the limit for contrast in the shortest frequencies and if you close down more than that you loose the "HD" in HDTV completely. In other words, you might as well have a SD camera cause your camera can't make HD. For a 1/3 inch chip zero contrast at the highest frequencies happens at F7. But because of the tiny size of the 1/3 inch chip, it doesn't take much before before you lose contrast fast at even wider f-stops and at 2.8 you get don't really do much better as you get about 65%. UGH! That graph of usable levels of light is a far shorter diagonal line on a 1/3 inch camera. So as far as you can stay away from F7 on a 1/3 inch chip camera and the more light you can let in by always shooting open as wide as you can, in addition to being as perfectly focused as possible, the more you are making the resolution the camera was designed to make. Of course as cheaper lenses on these cameras are often used, you end up having other aberration issues wide open but that’s another story. Want to see it all in action? You need a tripod, a camera and outdoors. Put ND on the lens and shoot any shot, a tree-lined driveway, etc for example making sure proper exposure gives you wide on you lens. Now take some ND out and shoot at f5.6. Now take more out until you are at f8. Now take you footage inside and do a split screen of the same shots at different f-stops. Notice how sharp and crisp the wide open looks and how miserable, soft and milky the closed down shot looks, sort of like a first generation DV camera. Welcome to physics.

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  • 1 month later...

I actually worked on a feature a while ago that did this (The Art of War 2) and it raised a few eyebrows when post swore it would cut together seamlessly. In fact, we probably shot a third of the film on the thing (it was a martial art heavy story, and the director loved the maneuverability of the thing). To be fair, I haven't seen it, and I'm sure the glaring flaws in the script would camouflage any glaring flaws in the cinematography, but it has been done at least once.

Edited by Dwight Hartnett
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