2012 High bitrate hacks... cards to keep up
 

Read several dozen threads now on the general topic, and I'm still not quite sure whether I can get the full benefit of some of these hacks without going out hdmi.

I realize part of the problem is that many threeads are old, and the recommendations are out no longer valid, so I just wanted to double check.

Likely ordering the camera today, and may want to tack on some cards to the order.

Basically, I see that the Sandisk extreme class 10 cards have a max rate of 30mbps, and some of the hacks are doing between 40-176mbps.

I must be missing something somewhere. Doesn't that mean the cards are incapable of capturing everything.

Is it compressing then? If so, what's being lost? Is it possible to get the exact same thing you would with live output... but captured on a card?

Still not clear after all this reading either whether the new crop of cards are any benefit over the class 10.

thx.

Re: 2012 High bitrate hacks... cards to keep up
 

Can you go any higher than class 10 without going to the SDXC and is the GH2 SDXC compatible?

Re: 2012 High bitrate hacks... cards to keep up
 

Well, that's what I meant by the new ones. I thought it was compatible, though may not be able to take full advantage of differences. Actually some conflicting info I've stumbled across on both points, though.

Basically, just wondering about what happens to everything over the card's bitrate and whether it's possible to do equivalent to live capture via hdmi.

Re: 2012 High bitrate hacks... cards to keep up
 

Got the same questions and am looking forward to the answers Greg.
I feel like I'm starting the learning curve from scratch.

Re: 2012 High bitrate hacks... cards to keep up
 

Well there's a missing piece somewhere, because I've dug up multiple threads where people say they're doing these high bitrate hacks...

... and the advice they get is to use the Sandisk extreme class 10 cards.


... which as near as I can tell won't support those bitrates.

Re: 2012 High bitrate hacks... cards to keep up
 

The cards are rated in terms of MBps (megabytes), whereas the patches are rated in terms of mbps (megabits).

1 byte equals 8 bits, so theoretically a 30 MBps card should be fast enough for anything up to 240 mbps; however, it's a good idea to have a large overhead in case the card hangs.

It gets more complicated when it comes to UHS-1 cards. The Sandisk Extreme HD video card is 30 MBps (like the Extreme III), but it relies on UHS-1 to get to that speed. If I recall correctly, the speed on the Extreme HD video without utilizing UHS-1 is only 20 MBps.
I'm not positive that the GH2 supports UHS-1, so you might be better off with a traditional Extreme III over an Extreme HD Video if you plan on using high bit rate hacks.

Re: 2012 High bitrate hacks... cards to keep up
 

Ahh... ok.

I knew there was a missed connection somewhere as the responses didn't seem to address the numbers not adding up.

I'll go back and reread some of it now.

Re: 2012 High bitrate hacks... cards to keep up
 

The card I am using for the latest Driftwood is SDHC 95MB/s, necessary if you want to span.

Re: 2012 High bitrate hacks... cards to keep up
 

Ahh... yeah. That's the other bit I was trying to remember.

So the extreme pro, then.

Gettin' pricey, but rather make sure I have the right tools than get stuck later.

Spanning aside, does that speed make a real difference in any other way?

Re: 2012 High bitrate hacks... cards to keep up
 

Found the answer...

Panasonic GH2 with UHS-I and SDXC - Personal View Talks
I've a couple of reports of SD UHS-1 working with the GH2 (a couple on this forum, one elsewhere, and digitalrev.com is actually bundling the GH2 with a UHS-I card), and UHS-I is faster than SDHC class 10, so it would seem to be the logical choice when pushing the bitrate limits.

However, there are also a couple of reports of UHS-I cards performing similar to a SDHC class 6. Also linked from the GH2 hack thread was this test: Benchmark Results: Read/Write Throughput : 10 SDXC/SDHC Memory Cards, Rounded Up And Benchmarked which seems to indicate current UHS-I cards may have slower continuous write speed than speed class 10 (though they have much faster read).

Also, the GH2 is compatible with SDXC according to the spec on the Panasonic website - but I see no discussion of results here yet.

Re: 2012 High bitrate hacks... cards to keep up
 

I've been using a Sandisk SDXC 45mb card so far. It works fine but I'm going to try a cheapie Transcend class 10, 64 gig today.

I normally avoid these like the the plague and wouldn't think about using one on a paying job, but....I'm reading a lot of people that are using them on the moderate bitrate hacks, with success.

It would be nice to be able to use a less expensive card but I'm not sure I'll ever be comfortable with one.

It's funny how some camera's can be picky about a card other cameras work great with. I have 12 GOPRO Hd1 and Hd2's. They are the most card finicky cameras I own. They work best with Sandisk class 6, 16 gig.

Re: 2012 High bitrate hacks... cards to keep up
 

I finally got a lockup with the Sandisk but not the Transcend.
I shut down and pulled the battery, then tried the Sandisk again. Worked fine that time.

Re: 2012 High bitrate hacks... cards to keep up
 

Well, camera, lens, and lighting are on their way, and my goal for the day today is to figure out and order any peripherals that are necessary to get rolling.

Mainly, that means an ac adapter for studio use, a tripod, and to get my direction chosen for recording.

I've been reading up as much as possible about blackmagic cards, ninja (REALLY don't want to have to spend more than the camera for recording solution), etc.

Overall, it's seeming more and more like the HDMI thing is just a potentially endless series of headaches that could shut down a shoot... and which in the end can actually cause some color issues while not outputting 4:2:2 which would have been my goal anyway.

Open to any contrary input, but it's looking for now like I should just focus on getting the highest stable quality I can from the cards, and get them ordered.

I've read a good bit now about the uhs-1 cards being crippled. Seeming more and more like going with the class 10 sandisk is the way to go.

Any other input before I pull the trigger?

Trying to also difinitively choose my hack, but I just don't feel like I am quite well enough informed at the moment.