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#1 Brandon Petrie

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Posted 10 January 2007 - 02:44 AM

I am thinking of getting the hvx200 but am a bit worried and much ignorant about it's recording options.

As far as I understand, in any of these under $10,000 HD cameras, HDV or DVCpro or the P2 cards, you are not going to get a full quality 1440x1080 image. Am I wrong on this? It sounds like the p2 cards are the closest.

Is it possible to get that full quality image with a firestore or something else? What is the closest you can get to that resolution actually?
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#2 Brian Drysdale

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Posted 10 January 2007 - 05:14 AM

The best quality from the prosumer cameras is recording the HD SDI from either a Canon XL H1 or a JVC 250 onto a hard drive. Phil Rhodes has been testing this and says his results will be published in Showreel magazine.

http://www.cinematog...mp;#entry145789

Remember to factor in the price of the P2 cards when you're budgeting for buying the HVX200
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#3 Peter J DeCrescenzo

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Posted 10 January 2007 - 09:45 AM

Hi Brandon,

This has been discussed in these forums and elsewhere before, but ...

Brian is right, and hopefully Phil will have some additional information for us next month after his tests.

It's important to not confuse the capabilities of a video recording/playback medium with those of a camcorder's lens, image sensors and processing electronics (over-sharpening, compression, noise, etc.). These vary enormously, and each imposes significant limitations on video quality.

For example, all consumer/prosumer (and some pro) camcorders video recording formats (DV, DVD-Video, DVCAM, DVCPRO-25, DVCPRO-HD, XDCAM, XDCAM-HD, HDCAM) are 8-bit color digital video recording formats. Further, all but the high-end (more expensive) formats use 4:1:1 or 4:2:0 color subsampling, not 4:2:2 or 4:4:4. I believe this is also true for home theater HD-DVD and Blu-ray HD video disc recording formats, too.

A few pro video recording formats, possibly DigitalBetacam (?) and the newest HDCAM-SR format, are 10-bit color digital video recording formats.

10-bit color is noticeably more color information compared to 8-bit, and 4:2:2 and 4:4:4 color subsampling results in noticeably more accurate color compared to 4:1:1 or 4:2:0.

When I say "noticeable", I mean you can see it with your own eyes on a good display -- depending on the subject matter. For example, the difference may be easy to see in a chroma-keyed SFX scene, but difficult to discern in a dark scene containing few colors or within relatively fast motion.

8-bit color using, say, 4:2:0 color subsampling, doesn't have to look bad, but there are many, many possible factors, not the least of which is the skill of the people designing, lighting and blocking the scene which is recorded.

Lens quality typically makes a huge difference. For example, there's often not much point recording on a relatively hi-res recording format (say DVCPRO-HD or HDCAM) using a cheap lens with relatively low resolution, CA artifacts, and other problems. Most of the difference in cost between a typical consumer/prosumer lens and a typical pro lens is due to the actual image quality it can produce. High-quality lenses are very difficult to make, and as a result are usually very expensive!

The size, resolution and sensitivity of a video camera's image sensors, whether CCD or CMOS, are important. Even the relative size and other characteristics of the pixels within the image sensor make a big difference. For example, there might not be much point recording onto, say, HDCAM if the cam's CCDs are relatively small (less than 1/3"), especially in low-light, or when using an f-stop higher than 5.6 or so. The result will be low-res and/or noisy video.

Over-sharpening (detail/edge enhancement), compression, noise, and so forth caused by a video camera's processing electronics are very important factors. For example, you could use a very high-quality HD/cinema lens on a high-end pro 2/3" 3-CCD camcorder, but if the cam's detail setting is at a typical (too-high) factory preset value, the video will probably look awful.

Likewise, video noise levels in many consumer & pro video recording formats is relatively high. On many consumer & prosumer cams the video noise level often produce awful-looking video. This is a pet peeve of mine. :-)

Most hard-disk-based (or solid-state memory chip/P2) recording systems only substitute a hard-disk-drive or a memory chip for a (more common) tape medium. There's no difference in video quality -- the data recorded is the same whether on a HDD, P2 or tape. So, for example, DVCPRO-HD is the same quality regardless of what media it's recorded on. Tape, P2, Firestore; it's all the same quality.

All of the above recording formats are highly compressed. For example, DV and DVCPRO-25 are compressed by a factor of at least 5. Some of the high-end formats are less-compressed, say by a factor of 2-3. Compression often results in noticeable loss of video quality.

Some hard-disk-drive-based systems can record very high-quality video in uncompressed 10-bit 4:2:2 or 4:4:4 form. Typically these HDD-based recording systems use "live" SDI or HD-SDI video & audio source signals available on higher-end video cameras. Most of these systems use multiple HDD array (RAID) systems and are built from new-ish, fast-model Mac or PC computers fitted with SDI/HD-SDI video capture cards (AJA, BlackMagic, etc.). There are also (relatively expensive) standalone boxes available from several companies (such as Rosendahl BonsaiDrive, S-Two, etc.).

Having said all that, as Phil and others have elsewhere stated, some of the new, relatively low-cost HD & HDV camcorders are capable of producing and recording video which looks pretty darn good -- better than their overall system specs would imply! But as they say, you can't make a silk purse from a sow's ear. As always, it's: Garbage in, garbage out.

Also, as David M., Richard B. & others are happy to point out, if you really want good-looking motion pictures, just shoot film -- instead of video! :-)

But no matter what, all is lost in the case of a poor script, bad production design, blotchy makeup, harsh lighting, awkward blocking, iffy acting, crappy directing, and so forth! :-)

Hope this helps, and enjoy your research!
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