Which Sandisk is best for Gh-1 1080/24P?

B

BrianBrook

Active member
I was all set to buy Sandisk Extreme III 30/MB class 6, 16 gig for about $100 when I found SanDisk Extreme HD Video 20/MB class 6, 16 gig for $75-I'd pay the extra no problem for a better card but using the GH-1 there wouldn't be any difference-right? BTW-the Extreme HD Video card just came out so I can't seem to find any reviews on it-anyone else using it w/ GH-1? Thanks in advance!
 
That's a class 4 card-do you shoot 1080/24p with that and no problems? I'm going with at least class 6 especially with Tester13 on the job!
 
BrianBrook said:
That's a class 4 card-do you shoot 1080/24p with that and no problems? I'm going with at least class 6 especially with Tester13 on the job!
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I'm not an arm-chair/forum video expert...alls I know how to do is go out and make a living with my camera...and the Sandisk Ultra II has been fine. I think the transfer rate of the card is probably way overkill for the GH1's consumer-grade data rate...but that's just my guess. Maybe the GH2 will need more. :D....hoping!

Knock on wood. :cheesy:
 
Yeah class 4 is definitely enough for the GH1. It's only 17mbps in both 1080p or 720p modes.

Having said that, getting faster cards will future proof you for other cameras you may get in the future. The one advantage you will find now if you get faster cards is the faster data rate when transferring to your computer.
 
deltoidjohn said:
Yeah class 4 is definitely enough for the GH1. It's only 17mbps in both 1080p or 720p modes.
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Alas...it is not so simple.

The GH1 user manual specifies Class 6+ for video. I believe they have good reasons for this requirement:

  1. The "speed class" of a SD(HC) card is based on a blank card with zero bad blocks. But in the real world, our cards have other files, and remapped blocks, and fragmentation, so real-world write speed can be lower.
  2. Speed class is measured at the manufacturer's discretion with some (unspecified) size or time of data transfer. A "Class 4" card that does 32Mbps for a long data transfer (e.g. 100MB), might do a much lower rate over 1 or 2 seconds. I have interfaced directly with SD & SDHC cards, and it is not unusual for their memory controllers to introduce large delays/latencies (many milliseconds) before a write is committed.
  3. File system controllers introduce even more latency. The FAT file systems used by our cameras become increasingly slow & inefficient as the number of files and amount of fragmentation increase.
  4. 17Mbps is the (average?) data rate of a final video file from the GH1. It does not represent the write speed. That file is written in short bursts of data that might far exceed 17Mbps.

Overall...the minimum SD card data rate is complicated & unpredictable, even for a camera maker. So...they do real-world tests with real-world memory cards during product development...and they specify a card "class" that will work close to 100% of the time.

For the GH1, that spec is Class 6 or higher. A Class 4 card might work, but no guarantees. It depends on the specific card, block allocation, instantaneous video bandwidth, and many other factors.

I would not gamble on a Class 4 card for 1080 or 720p video on this camera. Especially when Class 6 cards are so cheap. You can buy a good 16GB Class 6 card for less than $40.

FWIW...I own and use several different brands of SD(HC) card...SanDisk, SanDisk Ultra, Kingston, Transcend, PNY, and some other no-name brands. I have interfaced with some of these cards via microcontroller, with interesting results. You might be surprised which cards are fastest. :)

J
 
So how does PNY compare to other SD cards in your testings. I have a class 4 PNY that never gave me an issue with the GH1 but a class 6 Transcend has on the first day I really used it which was during this event:
http://vimeo.com/10662174

The clips have stop recording a few times because of write speed that the camera claims. I haven't had much problems since then but on a gig, I would probably trust my class 4 PNY more.

Still, I don't think you'll find much issues using a Sandisk class 6. Months ago, I have spent a lot of time thinking about rather or not I should spend the extra cash on a 16GB version and when I finally decided to take the plunge, I end up loosing it on the first day that I take it out. It pissed me off that instead of loosing any of my cheaper SDHC cards, I had to loose the the most expansive one.
 
I ended up going with the Sandisk Extreme HD Video 20/MB class 6-I'll use it for camera tests before a shoot I've lined up this summer. I really don't mind spending a little more for less problems down the line, it's easy to compromise w/ equipment but in the past it's always bitten me in the posterior!
 
My card is a 16GB Transcend Class 6, haven't yet had a problem with it. Still, I'll probably upgrade to a SanDisk Class 6 or 10 32GB and use the 16GB for my Zoom H4.
 
I couldn't find a SanDisk 32 MB Extreme III 30MB/s class 6 for less than $185, until it goes down it just make more sense to get two 16MB cards for less, plus it doubles the error probability.
 
i have been using for 6 months class6 8gb verbatim cards and i always had problems when going over 70% capacity... on power on the camera would report "memory card error" which forced me to turn off and on again... in 1024 i would usually get lots of speed error stops during recording ( and i had 4 cards so it's not only 1 ).
last week one card stopped working in camera ( "no memory card" error...) but the card can be used in a card reader on pc or mac...
so i finally bought 2 8g sandisk ExtermIII cards and used them extensively this weekend and had not one problem... well worth the extra money
 
Your post illustrates why I don't believe it's practical or even sensible to take the frugal route when it comes to cheap SDHC cards, plus my cards will be the eqivalent to "Master tapes" holding the archival original footage for my feature film, not a good area to save a few bucks-I reserve that for food and neccesities!
 
BrianBrook said:
I couldn't find a SanDisk 32 MB Extreme III 30MB/s class 6 for less than $185, until it goes down it just make more sense to get two 16MB cards for less, plus it doubles the error probability.
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You know, you can only record about 14 seconds of footage on 32MB and only 7 seconds on 16MB. Frankly, I'm surprised that you can find cards that small these days. :cheesy:

SanDisk is the biggest brand simply because it's the biggest manufacturer. That doesn't mean that its products are always the best.
 
Hello,

I'm new to the GH1 scene and I'm looking for a good memory card reader.

Here are my specs:

GH1 (soon hacked)
iMac 2.4 GHz intel Core 2 Duo
Sandisk Extreme, 4 GB, Class 10 memory cards

Thank you,

Trey
 
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