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January 27th, 2011, 05:53 PM | #1 |
Major Player
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Here's a question for you.
I was looking at the A1 specifications and I found that the HD and SD(16.9) have the same frame size, resolution and pixels.
HD approx. 1.56 Megapixels (1440 x 1080) SD (16:9) approx. 1.56 Megapixels (1440 x 1080) They are identical . So if I shoot SD (16.9) or HD the quality and file size are the same? Is this correct? It sure looks that way to me. Now standard SD SD (4:3) approx. 1.17 Megapixels (1080 x 1080) is not the same. So I'm presuming that the A1 down converts HD or SD (16.9) to create Standard SD (4.3). Correct? OK, So why not shoot SD (16.9) instead of HD, since SD (16.9) would be easier and faster to edit? ???? |
January 27th, 2011, 10:02 PM | #2 | |
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Wheras HDV will output to 1440x1080 pixels... |
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January 27th, 2011, 10:09 PM | #3 |
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I just double checked on the Web Site for the A1s. As per their own specs, the camera delivers SD (16:9) approx. 1.56 Megapixels (1440 x 1080).
?????? |
January 27th, 2011, 11:07 PM | #4 |
Inner Circle
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Hi, David...........
Not really my area of expertise, but I'l have a stab at this one, if I may.
I think where this all falls apart is between what the front end can aquire, and what the back end can write to tape, to keep within spec. The DV spec is pretty specific about what goes on the tape, the compression used and many other thngs as well. During the front end to back end journey, that aquisition has to be whittled down to what the DV spec allows on the tape, which is 720 X 480 pixels max, no matter what was taken in at the front end. Does the camera put out a higher resolution picture via the Firewire port during DV capture than is written to tape? Doubt it, otherwise any system designed for DV wouldn't be able to reckognise it, so it must be down sampled before it gets to that port. In short, no matter what the specs say, what is going in, is NOT what is coming out, as it MUST be DV compatible in SD mode. The overall bandwidth used during tape record of both SD and HD is pretty much identical, but there is a huge difference in the compression between the systems, which explains why the data rate is similar even though the data retrieved after is so much higher in HD. As to your specific question about shooting SD or HD to get editable SD footage, there are about 5,000 posts here that basically say the camera doesn't do as good a job of converting HD to SD as can be achieved in pretty well any decent NLE, so why shoot SD? If you're pushed for processing power or time, fine, shoot SD. Nearly everyone as posts on the subject say they get better results shoting HD then down converting. Heck, I'm not going to argue, I've never shot SD on the camera since I've had it. CS |
January 28th, 2011, 03:04 AM | #5 |
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Hi
Don't know what they mean with the SD resolution, it seems as the info you attatch is taken out of it's circumstances. To make it possible for us to help you must show more of the document or attatch a link to it. SD can never be HD resolution. A guess is that Canon mean that the whole CCD is used to capture SD. The picture will then ALWAYS be down converted to SD resolution, 720x480 (NTSC) or 720x576 (PAL) and stored that way on tape. Regards, /Bo |
January 28th, 2011, 08:06 AM | #6 |
Inner Circle
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David,
I agree with Chris' explanation. THe camera is using the whole sensor in SD 16:9 mode but down sampling it to standard DV format (720x480 anamorphic). You can prove this by recording to your MRC1K or to your computer directly. The resulting files will be 720x480 anamorphic. |
January 28th, 2011, 08:42 AM | #7 |
Major Player
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Then with the A1 there is no way to utilize the highest capabilities of the senor.
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January 28th, 2011, 08:56 AM | #8 |
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Yes there is. Shoot HDV (1440x1080). If you have need for SD, downconvert in post, nobody will see the difference.
Regards, /Bo |
January 28th, 2011, 08:48 PM | #9 |
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"Then with the A1 there is no way to utilize the highest capabilities of the senor. "
Yes there is..Learn about lighting and composition... David..... If you're planning on outputting to DVD, then stick to SD 16:9..It will save you the headaches of getting a downconvert.. If you're planning on delivering to BluRay or HD web, the stick to HDV 30fps ... Don't let the theoretical assumptions get in the way of having fun... Trust us on this...Go out and shoot!!! |
January 28th, 2011, 09:57 PM | #10 |
Major Player
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I'm shooting HD 30p. I have a friend looking for a backup camera and I suggested he purchase a used A1. That's when we read the A1s specs and noticed that the camera does SD (16:9) at approx. 1.56 Megapixels (1440 x 1080). Why Canon lists it like this in it's specs, I have no idea.
All it does is add to confusion. |
January 28th, 2011, 10:14 PM | #11 | |
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You will get far superior results if you shoot HD and use a quality down converting program such as VirtualDub (which is free) to get your SD footage. Most NLE's do a horrible job at resizing video, FCP, Adobe, and Sony Vegas are some of the worst. Yes, there is a longer workflow but it is worth it. I'd advise that you experiment for your self as I did. -Garrett |
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January 29th, 2011, 09:30 AM | #12 | |
Inner Circle
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Of course in this SD mode the camera is still shooting 1440 x 1080 (it's forced to when it's fitted with these chips) it's just that it does the down-conversion from HDV to SD on the fly, between chips and tape. tom. |
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February 3rd, 2011, 11:18 AM | #13 | |
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(Liquid is a bit of a "legacy" product now. It's cheaper, easier to use and all-round better than Avid's own Media Composer, so they've stopped developing it - IMHO, of course!! ;-) Therefore, I keep my eye out for alternatives. I haven't found one yet that makes better DVDs from HDV.)
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February 3rd, 2011, 06:16 PM | #14 |
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I'm using the A1 and AVID, mostly for SD productions, and this since roughly four years. I tested both ways quite thoroughly, shooting HDV and downconverting, as well as shooting in SD and going straight forward. May be I'm blind and dumb, but I couldn't figure out a significant difference. If you tweak the settings right, the A1 will give you great SD images right away. And you don't waste time with downconverting.
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February 3rd, 2011, 06:47 PM | #15 | ||
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Quote:
Quote:
-Garrett |
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