SD-Cards

Hi Muroshi, Class 4 is not enough for some high detail scenes (deep DOF). Class 6 minimum, ideally. You can buy Class 10 Transcend SDHC cards for cheap. As for the capacity of the card, it will "fill up" faster depending on the bitrate of the video, not just the frame size (1080p vs 720p).

Sorry I don't have the numbers to calculate for you.

Generally, 8GB is the minimum I would use without expecting frustrating moments of running out of space everyday. With the hacked GH1 I used a 16GB Transcend SDHC Class 10 card:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820208535

At that price, perhaps you could afford 2 or 3.

Another note, with SDHC cards, sadly brand name matters more than Class rating, as companies lie about actual read/write speeds. See this review, for example:

http://www.tomshardware.com/charts/sdhc-memory-card-charts/Minimum-Write-Transfer-Rates,864.html
 
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Thanks for your information. About 60$ for 32GB here. I don't have a notebook so I better get them bigger then.
 
DanDOF said:
With the hacked GH1 I used a 16GB Transcend SDHC Class 10 card:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820208535
Click to expand...

What am I missing here? The maximum AVCHD bit rate for the GH2 is 24Mb/sec, yet the above 16 GB card is rated at 20MB/s. What gives?

"Adhering to the new Class 10 specification, Transcend’s SDHC cards perform at a transfer rate up to 20MB/s on devices supporting SD 3.0, ensuring your device remains quick and responsive while recording and viewing files."


When I bought my GH2 I was also sold the recommended Class 10 16 GB SanDisk Extreme SDHC card with up to 30MB/s transfer ("200 X"). $150 vs $27 above (!!) Is all this over-kill? and how fast is quite fast enough?
 
Very good. 8 bits = 1 Byte.

Or 8 bits / second = 1 Byte / second

Or: 240 Megabits / second = 30 MegaBytes / second

So I'm using a 240 Megabits / second transfer rate card to record GH2 video that encodes at a rate of 24 Megabits / second. Why?

I know I'm missing something well,duh fundamental here. What is it?
 
I'm stumped, but what rate does a Class 4 card have anyway? Basically I suggest the OP to use Class 6 or higher.
 
From p.29 in the DMC-GH2 user manual:
http://dlc.panasonic-europe-service.com/EUDocs/

"... Use a card with SD Speed Class with “Class 4” or higher when recording motion pictures in [AVCHD]. Also, use a card with SD Speed Class with “Class 6” or higher when recording motion pictures in [MOTION JPEG]. ..."

It would be worth testing if using a class 10 card in a GH2 allows it to save stills (photos) faster than a slower card. And a class 10 card can typically transfer files from the card to your computer faster, when using a fast card reader.

But unless someone has found otherwise, for video recording & playback a GH2 only needs class 4 or 6, as described in the user manual.
 
A good class 4 will be enough for default bitrates. But if the Gh2 gets hacked you may very well need a faster card. 20MB/s is 160Mb/s but you have to remember that that speed is the peak speed, that is why they say "up to" sustained speeds can be much lower. Some cheaper cards are only fast in the first few portions of the card then get snail slow. That is why it is good to read independent reviews or tests that do sustained throughput test on the whole card.
 
The card reading and writing speed is quite decent the GH1 so it does pay to get a faster card it's noticeable when the buffer clears after taking quick succession shots.
 
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