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Old June 20th, 2007, 06:57 PM   #16
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It's just a different workflow and not a matter of one connection superseding another.

Some users use firewire capture in the native DV or HDV codec with timecode and deck control. They may choose to re-encode the captured footage to another format after capturing.

Others will use HDMI, capture to their codec of choice and use firewire for deck control and still retain time code information. This way, they use the camera's hardware filtering to regain the 4:2:2 signal out of the camera.

Some other users capture live of the camera via HDMI into Uncompressed codec for green screen work bypassing HDV compressing to tape altogether.
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Old June 21st, 2007, 08:24 AM   #17
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Others will use HDMI, capture to their codec of choice and use firewire for deck control and still retain time code information. This way, they use the camera's hardware filtering to regain the 4:2:2 signal out of the camera.
Please explain how you regain a 4:2:2 signal when all you have to start out with is 4:2:0. Is it the Wizard of Oz at work? How can you retain time code info, when is has been lost during HDMI transfer? What about all the other data thrown away during transfer with HDMI?

You make it sound like you drive your Trabant into your garage, attach the charger to your battery and expect to drive out of your garage driving a Bentley. Just to make it clear, even with charged batteries a Trabant is still a Trabant.
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Old June 21st, 2007, 09:48 PM   #18
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The HDMI output is a YUV 4:2:2 video signal and is derived by the camera's internal hardware processing from the HDV footage on tape. As mentioned previously, timecode is captured because it comes in via firewire as the NLEs use that as the timecode source when not using DV or HDV. This is similar to capturing HD-SDI and getting time code from the RS422 control. Other data will not be captured.
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Old June 22nd, 2007, 04:16 AM   #19
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concrete question about HDMI capture

Im just learning about this issue, so forgive me my ignorance:

would it be better quality (lets say color space) an HDV-on-tape image captured by HDMI to AspectHD, than by firewire to AspectHD?
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Old June 22nd, 2007, 03:50 PM   #20
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My whole reason for going with HDMI capture was that I heard it was higher resolution than Firewire: 1920x1080 (HDMI) vs 1440x1080 (Firewire). It appears this may be a myth? And if HDMI captures contain no timecode, I don't undertsnad all the hoopla. It MUST contain SOME sort of time stamp, no?
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Old June 22nd, 2007, 05:12 PM   #21
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My whole reason for going with HDMI capture was that I heard it was higher resolution than Firewire: 1920x1080 (HDMI) vs 1440x1080 (Firewire). It appears this may be a myth? And if HDMI captures contain no timecode, I don't undertsnad all the hoopla. It MUST contain SOME sort of time stamp, no?
IMO it is all a myth. Once your signal is on tape, it is recorded at 1440x1080 in a 4:2:0 color space and heavily compressed. If you add some arbitrary bits to make it into 4:2:2 color space, it does not add information, it just adds some arbitrary bits that were lost previously, not meaningful information. A second thing to consider is the placement of the HDI chip in relation to the DSP. In most consumer camera's it is placed after the DSP, which means that the original signal (1920x1080) has been converted to 1440x1080 with a PAR of 1.333.

Look at it as if it were taxation. You earn $ 1000, the IRS comes along and they have you pay your taxes, say $ 800 (yeah, they are greedy), so you end up with $ 200. Whatever you do, your spending power is limited to $ 200, unless you find a way the IRS does not stop by (HD-SDI or HDMI live). Where and how you spend that $ 200 amount is up to you, just as HDMI or fire wire. But there is no way you can make that $ 200 into $ 500 or more without cheating the system.

Signals once recorded at 4:2:0 can be artificially converted to 4:2:2 color space, but do not gain you anything. Just like the $ 200 can be changed into other denominations, but will not by some magical trick amount to $ 500.

Just my 0.02 cents
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Old June 23rd, 2007, 12:38 AM   #22
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HDMI Cont'd

I'm using HDMI now to connect to Sony 40x series LCD TV with the Canon HV20. Suppossedly 1080p LCD TV, Having shot on Sony High Def tape. Sony also tell me the two HDMI ports are HDMI 1.3 Standard. Yet I can not find this on any Sony specs.We are told HDMI 1.3 will be more future proof for handling far more data. The Camcorder is supposed to be true HD. Yet I only ever get 1080i. It all seems to be some kind of Joke. Some HDMI Gold/silver cables costing up to hundreds of dollars to just a few. HDMI is HDMI should handle the standard whatever the cost. The only advantage to me is connecting one cable with the video signal also instead of two cables.
I Have yet to see 1080P on my latest Sony model from any source. Even latest games on Sony PS3 are only 720p.
Bought my HDMI cable for around $25.
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