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Canon EOS Crop Sensor for HD
APS-C sensor cameras including the 80D, 70D, 7D Mk. II, 7D, EOS M and Rebel models for HD video recording.


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Old September 20th, 2009, 02:23 PM   #16
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He's a marketing guy, rather than an engineer. Still, it's good when a marketing person understands use cases and user needs.

Also, as a marketing person, he probably didn't realize that the engineers would probably not want any information about their scanning structure to be hinted at in public. ;)

Anyway, that video is definitely worth watching...
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Old September 20th, 2009, 09:20 PM   #17
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Originally Posted by Chris Barcellos View Post
I am not sure how technically competent he is, as he seems to believe file size can be increased by a hack. My understanding is that file size (at least in HiDef) is limited by the 4 gig maximum size.
The problem is that the CF card standard requires that the cards have been formatted with either FAT16 or FAT32 (which the 5d2 uses) file systems. These days, most CF cards use FAT32 and this file system limits individual files to a maximum of 4 GB (HD or SD, there's no difference). The newer versions of Windows use the NTFS files system for its hard drives and they don't have this file size limitation.

But a file system is software. You theoretically can format a CF Card in a number of other ways (NTFS for example) or alternatively, you could produces a proprietary card that fits in a CF slot. But the camera would have to be reprogrammed to read and write to the CF Card using an alternate file system. And once you go this route, then you have to worry whether the CF card would work on a Mac (which can usually read NTFS formatted devices, but not write to them without using some tricks). Another problem is that small capacity CF cards use a lot of overhead (which shows up as unusable storage) when formatted as NTFS. But on bigger capacity cards, this problem is negligible.

BTW, those two Tim Smith videos really formalize the "legend" of the 5d2. Just about everything we know about the camera and its development appears to be correct. I'm also now convinced that the camera bins 6 pixels to get 1920 x 1080 video.
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Old September 20th, 2009, 10:01 PM   #18
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[...] He also confirms that they don't pixel skip. They bin them in groups of six to pull down to 1080.
It looks like a duck, walks like a duck, and quacks like a duck. But Canon Marketing says it is NOT a duck. If Marketing really is telling the truth, and they really are binning all the pixels on the sensor, then they are doing a stupendously terrible job of it, because the noise and moire is as bad as if they were reading only 1/3 rows.
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Old September 21st, 2009, 01:49 AM   #19
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Binning will also cause moire. It will also cause the chroma artifacts that we see. If they just read lines and filtered them properly, there would be no chroma artifacts per line on B&W images, and line skipping wouldn't add any chroma artifacts. As far as the noise goes, I'll take your word for it. I've never done the photo/video noise comparison.

Anyway, mysteries remain...

I expect that a future 1D-series cam will have the read speed and processing to be able to read the photo-sites and filter them properly. Or at least, for $5k+ or whatever they'll charge, it should...
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Old November 16th, 2009, 05:33 AM   #20
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Originally Posted by Daniel Browning View Post
It looks like a duck, walks like a duck, and quacks like a duck. But Canon Marketing says it is NOT a duck. If Marketing really is telling the truth, and they really are binning all the pixels on the sensor, then they are doing a stupendously terrible job of it, because the noise and moire is as bad as if they were reading only 1/3 rows.
There has been more analysis that shows Canon did not tell the truth. They are indeed skipping 2/3 rows:

Re: Update considering Canon's claim of 6 pixel binning: Open Talk Forum: Digital Photography Review

video from DSLRs: every third line used? - Luminous Landscape Forum
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Old November 16th, 2009, 09:52 AM   #21
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I wonder if the marketing guy spoke out of turn. It's unlikely that a marketing person would come up with that off the top of his head.

Given the low noise of the 1D4, maybe that's the binning camera...
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Old November 16th, 2009, 12:04 PM   #22
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Well, it sounded like he'd asked the engineers...

DSPographer is perhaps saying something along a compromise between both camps? He says the magnitude of the horizontal aliasing is consistent with binning three alternate same-color pixels per row (which would mean three out of six, perhaps where the "six pixel bin" idea comes from?)

However, on the vertical, he says the magnitude and the frequencies are consistent with 1-out-of-3 skipping.

But Tim Smith did flatly deny any pixel-skipping...

So maybe it bins three (out of six) together on the horizontal, and only takes one out of three vertically. That would make it effectively reading 1/9 of the sensor, or 2 megapixels out of 18. Which should give it the speed necessary to do 720/60p as well...

EDIT: Now that I go back through that thread, I see that's exactly what DSPographer was suggesting three weeks ago -- binning three consecutive same-color (out of six) on the horz, and skipping 2 out of three on the vert, to create an 1872x1053 image. Then demosaic'ing and scaling to 1920x1080. Which, if it's an 1872x1053 image before demosaic, that would explain its basically 720p res after demosaic (assuming about a 30% res loss due to the demosaic process).
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Old November 16th, 2009, 01:59 PM   #23
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Given the low noise of the 1D4, maybe that's the binning camera...
Yes, that could be it. It will be interesting to see it pointed to a zone plate after it hits the streets.

DSPographer just posted his test images and analysis of the horizontal and vertical frequency sweeps.
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