HDMI Editing and uncompressed HD footage

prisma

prisma

Member
What are the advantages to use a HDMI capture card like the blackmagic to import uncompresed HD footage from a HD camera? How much hard drive space from an external firewire disk would be needed for a 17 to 40 minutes film? Also, if you edit with uncompress HD what do you do with that footage once you finish editing? I mean do you need to burn it with a blue ray DVD? an HD DVD? or you can just burn a dual layer DVD and play the film in a HD DVD player? Can a normal dual layer DVD burner burn HD DVD media? sorry to ask to many questions but im really confused rigth now. There is limited information about this on the internet. and the information that is available sometimes is contradictory.

Thank you guys.
 
Another question: Do you really need the balckmagic to capture uncompress HD (8bit - 10 bit) or there is a way (workaround) to capture it via firewire? also, if you video card has HD display capabilities (like my nvidia 7600GT) can you do color correction of your HD footage on your HD flat monitor with a DVI-O port?

sorry to ask to many questions :embarasse
 
You can't capture uncompressed over firewire because the data rate of HD is too high. The only advantage of uncompressed HD editing is you bypass whatever compresssion the camera is introducing to the footage. For example, uncompressed HDV footage would retain the 4:2:2 color space vs. the compressed color space of 4:2:0. Visually there is very little difference between the two but where it counts is if you plan to do heavy color correction/green screening then you want as much color information as possible.

I'm not too sure about how much space uncompressed HD will take up for 17-40 mintues I would expect at least more than 1 TB of space. You don't want to shoot the whole film uncompressed anyway. There's no way of doing it unless you bring your computer along and tether the camera to it while recording, making recording uncompressed useful only for very specific studio situations. Editing wise uncompressed HD will completely kill your computer's performances unless you have a very fast hard drive system, preferably RAID together. The graphic card won't help you there. But if you ever manage to get it edited then the footage is exactly like normal footage. It can be burned on to Blu-Ray or HD-DVD and played in a compatible player but not on a double layer disk (except as data).
 
jade8472 said:
For example, uncompressed HDV footage would retain the 4:2:2 color space vs. the compressed color space of 4:2:0.
Click to expand...

HDV can't "retain" that which it never had. HDV is 4:2:0.

Transferring your footage via HDMI won't magically give you back that last bit of color information that was never recorded.
 
mcgeedigital said:
HDV can't "retain" that which it never had. HDV is 4:2:0.

Transferring your footage via HDMI won't magically give you back that last bit of color information that was never recorded.
Click to expand...
Image is read in camera internally as 4:2:2, then HDV encoded to 4:2:0 for output through firewire. Capturing via HDMI or analog component bypasses HDV compression and gives you 4:2:2 color space. This is true for the A1, the V1U and the upcoming HV20.
 
Capturing from tape via HDMI I understand that it will not make the footage any better but. Will it make it easer to use in post?
 
That depends on what your capturing and what your idea of easier is.

If your capturing from an HDV camera then I believe its easier because your no longer editing HDV natively, however you will need a lot more disk space and significantly faster I/O.

Uncompressed 4:4:4 HD is approximately 192MB/s, 4:2:2 is a little less. I doubt such a small inexpensive card could capture that much data without compressing it somewhere. So I take that back...

I think the Blackmagic codec for this card uses motion jpeg, not a good compressor for editing, I imagine if you look closely you'll see jpeg artifacts - especially around text etc.
If that's the case you may want to check out alternative codecs like Cineform.

But basically I don't know, however, if I'm correct about the Blackmagic codec then there's a reall possibility that the quality will not be that great especially if your capturing from HDV tape. You'll have jpeg compressed HDV - that can't look good...

These might be good questions to answer before purchasing though. If you do purchase this card maybe you could share your experiences.
 
I just got this card in my new dual quad core. I can't get it to work yet. I can't find any support for it either.
 
Uh. What system are you on? Mac or PC first off? have you gone to the site? There's a lot of iNtensity support on the Blackmagic site.
 
Yes I have been to their site that is where I started. I followed the directions that came with the card but I can’t get it to work. I don’t see a user forum on their site so I was looking for someone that has the card and was able to get it to work for some insight.
I am sure I have a operator malfunction of some sort that I must overcome. My system is a PC dual quad setup just got it yesterday.
 
I would call there support line, I called about a problem with the intensity card and thre tech support was very nice and actually helpfull!
 
Ronbo said:
Yes I have been to their site that is where I started. I followed the directions that came with the card but I can’t get it to work. I don’t see a user forum on their site so I was looking for someone that has the card and was able to get it to work for some insight.
I am sure I have a operator malfunction of some sort that I must overcome. My system is a PC dual quad setup just got it yesterday.
Click to expand...
Is the card plugged into a PCIexpress x1 or greater slot? Or just a PCI slot? Can't be in just a regular PCI slot. This is what forced me to change my Core 2 setup.
 
I kinda have it working now.

When I capture in premiere pro under the blackmagic presets there is no video playing in the capture screen but the video is there after I close the capture window.

But it won’t play on the blackmagic timeline if I open it in an hdv project it will play.
 
Is anyone using this card? If so can you tell me your work flow? Right now mine is capture using black magic presets then close that project open a new project import the video and edit from there. This makes no sense. Why won’t the video play on the BM timeline? I guess I will have to call the company and see if this is the way this thing is intended to work.
 
MiniMan13 you have the intensity card? How is it working for you? Are you using it to capture 422 avi or mjpeg?
 
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