Is there any harm in using a class 2 sdhc card in a pocket hd camcorder?

[yoda313]

So is there any harm in using a class 2 sdhc card in a pocket hd camera?

I was informed by a sales clerk that it should be a class 4 or higher sd card for hd.

My family just bought the kodak zi8 hd cam. It actually does recognize and record to class 2 sdhc micro sd cards (I am using an adapter for the micro card as its slot is for a full size sdhc card. )

I think we'll be using 720p60fps for most occasions for recording. Is class 2 ok for this? Will there be any side effects for using a lower rated card for hd recording?

[aedipuss]

i'd guess it will work most times... until it can't write to the card fast enough, then it will crash and create a corrupt file, probably during something important and irreplaceable. up to you.

[yoda313]

i'd guess it will work most times... until it can't write to the card fast enough, then it will crash and create a corrupt file, probably during something important and irreplaceable. up to you.

So the class really does matter for hd recording?

I guess I'll just be using this for beginner use where I'm not planning on preserving the files.

Will a class 4 be the minimum to get? How many classes are there? What is the recommended transfer rate?

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Also the 8gb class 2 card I have shows just over an hour of recording space for 720p60fps on a blank card (7.38gb actual). So am I right in deducing that a 16gb card will allow for 2 hours at 720p60fps?

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Thanks for the responses......

[edDV]

i'd guess it will work most times... until it can't write to the card fast enough, then it will crash and create a corrupt file, probably during something important and irreplaceable. up to you.

So the class really does matter for hd recording?

I guess I'll just be using this for beginner use where I'm not planning on preserving the files.

Will a class 4 be the minimum to get? How many classes are there? What is the recommended transfer rate?

-----------------------------

Also the 8gb class 2 card I have shows just over an hour of recording space for 720p60fps on a blank card (7.38gb actual). So am I right in deducing that a 16gb card will allow for 2 hours at 720p60fps?

---------------------------------

Thanks for the responses......

The "class" or "level" of flash media refers to the sustained write/read bit rate they can handle. Note that is spec degrades as the media fills or with number of record/erase cycles.

A "class 2" card is usually sufficient for taking still pictures but is inadequate for higher quality HD video modes. It may work at the 8 Mb/s setting or less. Even at 8 Mb/s it is on the edge for reliability.

For standard AVCHD modes (17Mb/s or 24 Mb/s) , level 4 to level 6 cards are needed. The manual will say which is needed for your particular camcorder.

[jagabo]

http://www.sdcard.org/developers/tech/speed_class/

[yoda313]

Thanks everyone.

For standard AVCHD modes (17Mb/s or 24 Mb/s) , level 4 to level 6 cards are needed. The manual will say which is needed for your particular camcorder.

Unfortunately the manual just says it supports up to 32gb it doesn't specify classes or transfer rates. I did get this off of kodaks website:

NOTE:When recording/playing HD video, we recommend the fastest possible card. Class 6 cards are the fastest currently available.

So I should invest in a class 6 then? I'll check em out.

Thanks for the information everyone.

[Doug2dvd]

I use 16gb Adata class 6 card in my Kodak Playsport. It records about 3 hours of HD video. I would recommend an 8gb card. When the card gets about half full the camera is slow to access the memory. Video starts/stops are slower and browsing files gets slow. I don't know if this is because of the cheap card I bought or is camera CPU is just slow.

[yoda313]

Kodak Playsport

That was actually the camera we were going to buy but the zi8 was being discontinued and had more features for less money (plus we didn't need the waterproof feature).

16gb Adata class 6 card............................It records about 3 hours of HD video

Is that continuous 3 hours or does it record in multiple files? I don't know that I'd ever be recording that long continuously but I would like the option. Is that the 720p 30fps mode?

I would recommend an 8gb card. When the card gets about half full the camera is slow to access the memory. Video starts/stops are slower and browsing files gets slow.

I'd like to have the ability to record 2 hours - if it weren't too much more I wouldn't mind the 16gb. When you say start and stops are slow do you mean just playback or does it actually hinder the reaction time from hitting record to the time it actually starts recording?

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Thanks again for all the info. I'm pretty hd literate but obviously this is my first foray into hd video recording.

[Doug2dvd]

Kodak Playsport

That was actually the camera we were going to buy but the zi8 was being discontinued and had more features for less money (plus we didn't need the waterproof feature).

16gb Adata class 6 card............................It records about 3 hours of HD video

Is that continuous 3 hours or does it record in multiple files? I don't know that I'd ever be recording that long continuously but I would like the option. Is that the 720p 30fps mode?

I would recommend an 8gb card. When the card gets about half full the camera is slow to access the memory. Video starts/stops are slower and browsing files gets slow.

I'd like to have the ability to record 2 hours - if it weren't too much more I wouldn't mind the 16gb. When you say start and stops are slow do you mean just playback or does it actually hinder the reaction time from hitting record to the time it actually starts recording?

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Thanks again for all the info. I'm pretty hd literate but obviously this is my first foray into hd video recording.

I really like the playsport. It is cheap, small, and has a decent picture for my uses.

3 hours recording is for 720p 60fps or 1080p 30fps. 720p 30 fps gets about 4 hours on the 16 gb card.

I usually record only 1-2 minutes clips but I think if you recorded straight for an hour or so you would get one big file.

The slowdown is just when you hit the button or navigate the menus. The actual recording does not slow down. When I record for the first hour or son on an empty card I don't notice any lag.

[lordsmurf]

I use a piece-of-crap 16GB Adata CompactFlash in my Nikon D3s, and it records 720p just fine. That same card hangs itself when shooting even 5fps of still images. The buffer cannot empty quick enough to the card on continuous shooting. But apparently HD video is less demanding than tons of stills. I've dedicated that card to Slot 2 for video only.

I've not looked into it deeper. I'm sure there's a logical reason (backed up with some math).

[edDV]

I use a piece-of-crap 16GB Adata CompactFlash in my Nikon D3s, and it records 720p just fine. That same card hangs itself when shooting even 5fps of still images. The buffer cannot empty quick enough to the card on continuous shooting. But apparently HD video is less demanding than tons of stills. I've dedicated that card to Slot 2 for video only.

I've not looked into it deeper. I'm sure there's a logical reason (backed up with some math).

1080 60i and 720 60p need about the same bit rate. 720 30p (e.g. AVCHD Lite) uses half but will appear stepped in motion on a large screen HDTV. 1080 60p needs about double the bit rate of 1080 60i.

Keep in mind that 1280x720 is less than one Megapixel per frame. Stills generally use 24 bits per pixel for 4:4:4 RGB. AVCHD video uses 4:2:0 (12 bits per luma pixel average per frame).

[yoda313]

Thanks for the discussions guys.

I couldn't really get a hold of a class 6 card.

I got a san disk ultra class 4 sdhc 8gb card.

It is the one that says up to 15mb/s 100x (it does mention write speed will be slower).

I think it seems to be good. I did a test where I recorded a short clip and then stopped and started a new segment and it seemed to pick up almost immediately when I clicked the record button.

I think this should do well.

I appreciate all the advice.

[edDV]

Reliability is the issue. Keep in mind the defragmentation issues.

If you don't care if some clips go wiggy, experiment and let us know.

[yoda313]

@eddv - defragmentation? So do I need to defrag the memory card regularly?

And by the way - wiggy????? Is that a technical term I haven't come across yet?

[lordsmurf]

It's 720/24p on the D3s.

[edDV]

@eddv - defragmentation? So do I need to defrag the memory card regularly?

And by the way - wiggy????? Is that a technical term I haven't come across yet?

The way I understand flash media, they deteriorate or "wear" with write cycles. Defragmentation causes a flurry of writes as the files are moved and reconstructed. There may be less wear if you simply move the files to a hard drive leaving an empty flash card.

By "wiggy" I mean lost data (pixels, lines, fields, frames). Some of these will be masked by error correction. If you push more data to flash memory than it can sustain, buffers fill and eventually data is lost. The designers of the hardware choose when to warn you with error reporting or just let it happen.

[jagabo]

I got a san disk ultra class 4 sdhc 8gb card.

It is the one that says up to 15mb/s 100x (it does mention write speed will be slower).

I think it seems to be good. I did a test where I recorded a short clip and then stopped and started a new segment and it seemed to pick up almost immediately when I clicked the record button.

If the camera can't spool the video from its internal buffer to the flash card fast enough -- what I've usually seen happen is the camera just stops recording when the internal buffer is full. The amount of time this takes varies depending on the size of the internal buffer, speed of the card, and bitrate of the recording. The way to test if your card is fast enough is to make a long recording then check it for artifacts.

[yoda313]

The way to test if your card is fast enough is to make a long recording then check it for artifacts.

Thanks. I'll try that.

they deteriorate or "wear" with write cycles.

Is there an estimated life span for flash for video cameras? Or is it better just to buy a new one every year or two?

Also I envision offloading most clips and leaving the card virtually empty most of the time - except for trips when copying can be problematic.

[edDV]

they deteriorate or "wear" with write cycles.

Is there an estimated life span for flash for video cameras? Or is it better just to buy a new one every year or two?

The "this" is the flash card not the camcorder except for any internal flash RAM.