Graeme Nattress
Forum Replies Created
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I’m told that the “best” SD camera around is the SDX900. I’m very much looking forwards to seeing what the DVCpro50 mode looks like on the HVX….
Graeme
– http://www.nattress.com – Film Effects for FCP
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I think Panasonic want cheaper solutions for people and themselves. The introduction of this camera is one way they hope to bring costs down.
Graeme
– http://www.nattress.com – Film Effects for FCP
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I think the P2 cards need the “extra” reliability due to them being 4 SD cards in a RAID 0 configuration, so each card has to be 4 times as reliable to equate to the reliability of a single card in a digital camera.
Graeme
– http://www.nattress.com – Film Effects for FCP
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Sure, if you bring it in over SDI and edit it totally uncompressed. But that’s a pain and it’s expensive. The 24pA Panasonic solution is just so much better.
Graeme
– http://www.nattress.com – Film Effects for FCP
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Thanks. Yes, that was a good event.
Indeed yes, as long as the end result at 1080p looks good, then everyone will be happy. As I’m quoted as saying, I want high definition, not just high resolution!
Graeme
– http://www.nattress.com – Film Effects for FCP
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But the Varicam has 1280×720 CCDs, so somehow I don’t think the information you got was totally correct.
Graeme
– http://www.nattress.com – Film Effects for FCP
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Excellent post!
Does the camera have a physical anti-alias filter, and if so, does it go infront of the prism block, or infront of each CCD? Also, how the anti-aliassing filters “strength” work with the pixel offset??
The only mathematical paper I’ve read on anything close to pixel offset was showing how that the CCDs need to alias so that you can use the pixel offset to create an image of higher resolution that’s not aliassed, and the figure they were using was if the undersampling factor is n, then you need n^2 shifted CCDs to recreate that. In our case, we have 2 shifted CCDs, which would give a 1.414 undersampling factor. The paper was using vibration in a single CCD over time as the shift to recreate a higher resolution black and white infra-red image, so I don’t know how applicable their findings are to our 3CCD colour situation.
If anyone has any more information on this, then I’d really like to learn more.
Graeme
– http://www.nattress.com – Film Effects for FCP
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The CCDs can take in a range of light that is quite large. To fit this range better into video, and to get around some of the limitations of 8bit video, the image is gamma corrected to about 0.45 before being turned into 8bit video. This obviously needs to be done at a higher precision than 8bits to make the 8bit result as good as possible. Monitors have a gamma of about 2.2, which cancels out the 0.45 gamma correction so that we again see the correct image upon display.
The limits of DSP bit depth are really the noise floor of the CCD and the type of processing that you want the DSP to do. 14 bits sounds more than enough, but I’m surprised that they just don’t go to 16bits as word lengths of 16 usually compute better, even if it’s offering an extra 2 bits you don’t need. Any video DSP programmers here?
Graeme
– http://www.nattress.com – Film Effects for FCP
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Thanks Jan – that’s good to know. A good DSP makes all the difference!
Graeme
– http://www.nattress.com – Film Effects for FCP
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Sorry. Nobody knows what the A to D converter will be, or the DSP. However, DVCproHD is an 8bit format, if that helps.
Graeme
– http://www.nattress.com – Film Effects for FCP