Intensity and HDV

[Luke Maslen]

Hi Pablo,

Wow, you’ve asked a lot of good questions!

[Pablo Hill] “I know that if I capture trough HDMI my files will be a lot bigger, but will I have a better quality? What will my benefits be?”

If you capture video live from your camera through the Intensity card, you will bypass the compression to tape or flash disk and capture uncompressed 4:2:2 quality.

If you have already recorded to tape or flash disk, you will not increase the video quality by capturing via HDMI as compression has already occurred. However by capturing via HDMI, you will be able to capture in to a convenient, professional codec for editing. If you capture to an uncompressed timeline, you will not only retain the maximum quality of your video but you can then render and add effects as much as you like without any generational loss of quality.

As you know, codecs such as HDV and AVCHD use long-GOP compression. This is frustrating when editing because you cannot place your edits wherever you like and you are often forced to make them a few frames before or after point at which you wanted to make an edit. By capturing via the HDMI output of your camera, you not only retain maximum quality of your video but you can capture to an intra-frame codec which means that every frame is self-contained and you can edit anywhere you like. You can capture to professional compressed codecs such as ProRes, DVCPRO HD and PhotoJPEG or, to avoid any generational loss of quality, you can capture to an uncompressed timeline. The choice is yours.

For example, if you want to capture video and then add text and graphics prior to burning a DVD, it would be best to capture to an uncompressed timeline so that the text and graphics remain sharp during the editing process prior to encoding for DVD. If you capture to a compressed timeline, you’ll notice the edges of your text and graphics are likely to be soft and this will look even software and/or suffer from conspicuous compression artifacts when encoding for DVD. These compression artifacts will be far less prevalent if you have worked on an uncompressed timeline.

If you are intending to send video back out through Firewire, then you should go with Firewire for both ingest and output. However if you are not outputting through Firewire, then capturing via Intensity makes a lot of sense.

[Pablo Hill] “is my setup enough and how will I be able to control the deck if I’m not connected using firewire? Or maby I should stick with firewire.”

The Intensity Pro card is not suited for use with a Betacam SP deck. It lacks RS-422 device control and the audio inputs and outputs use HiFi level audio on RCA connections rather than the professional balanced XLR audio required by the Betacam SP deck. If you want a card for use with professional and broadcast decks, as well as for capturing the HDMI output of prosumer cameras, then the DeckLink HD Extreme 2 card has all the connections you need. It has professional and consumer breakout cables for connecting to almost any video and audio equipment and the cost is US$995. It also includes RS-422 device control and reference input for locking to other devices. It even includes 3 Gb/s SDI connections for use with existing SD and HD SDI equipment and new 3 Gb/s SDI hardware which supports up to 2K film quality via a single BNC cable.

[Pablo Hill] “I know that’s a lot but I have this going around in my head for the last week and the web does not have an answer for such a specific setup. “

You’re questions are the right questions to ask before starting your projects so please ask more if there is anything that isn’t clear.

Regards,

Luke Maslen
Blackmagic Design