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-   -   SDXC can you record longer than 4gb/12 mins? (https://www.dvinfo.net/forum/photo-hd-video-d-slr-others/486773-sdxc-can-you-record-longer-than-4gb-12-mins.html)

Dave Morgan October 29th, 2010 01:01 AM

SDXC can you record longer than 4gb/12 mins?
 
im going to be getting a sony a580 and am trying to find out if by using a SDXC card if you can record video longer than the normal using a SDHC card?

Daniel von Euw October 29th, 2010 04:39 AM

I have the same question about the 550D / T2i.

SDXC cards with exFAT filesystem should be able to do this.


regards
Daniel

Kin Lau October 29th, 2010 07:39 AM

For cameras with a 4gig limit, you have to work around it. The firmware is deliberately crippled, there's nothing you can do to change it.

Daniel von Euw October 29th, 2010 08:08 AM

The 4gig limit is not a problem of a "crippled" firmware - its a filesystem issue.

SD, SDHC und CF Cards use filesystems that support only files up to 4gig.

SDXC cards use exFAT filesystem that support files with over 4gig.


regards
Daniel

Perrone Ford October 29th, 2010 08:21 AM

Quote:

Originally Posted by Daniel von Euw (Post 1583436)
The 4gig limit is not a problem of a "crippled" firmware - its a filesystem issue.

SD, SDHC und CF Cards use filesystems that support only files up to 4gig.

SDXC cards use exFAT filesystem that support files with over 4gig.


regards
Daniel

Sorry, not true at all. My EX1 uses FAT and I can record continuously until the card is full. Whether that be 1 hour or 20. The camera simply closes one file, then opens a new one for writing. This has been done since tapeless cameras were brought on the market. The makers of these cameras have chosen not to implement this. It is a deliberate choice.

Daniel von Euw October 29th, 2010 09:05 AM

@Perrone Ford:

My and Dave's question was not why the sony or canon DSLR's do not beginn a new file after reaching the 4gig filesize.

Our question is what happend with SDXC cards?

Will the camera write also only 4gig files tought no technical reason exists?

Or will it write up to 29:59 min if the camera does not overheat?

Have someone testet this with SDXC cards?


regards
Daniel

Kin Lau October 29th, 2010 09:37 AM

It's a _design_ decision. After stated many times before, file spanning works _fine_, Canon and others simply _chose_ not to implement it due to EU tax laws. Simple as that.

My Canon HF100 and Panasonic GH1 both work fine with SDHC and FAT file systems, and there's no software record limit.

Daniel von Euw October 29th, 2010 11:05 AM

I knew that file spanning works fine and that it's a design decision to do it or not.

But with SDXC and exFAT you don't need file spanning to record more than 12 min and due to EU tax laws its allow to record up to 29:59 min.

So you knew from personal experience that also with SDXC cards the camera stop by 4gig filesize?


regards
Daniel

Buba Kastorski October 29th, 2010 03:00 PM

I don't think it matters if SDXC supports files larger than 4Gb, I can format sd card with NTFS, pop it into EX1, and it will have to re-format it to FAT in order to be able to record, so the question is if your camera will support other tha FAT FS.

Chris Leong November 13th, 2010 10:48 PM

There's a sensor heating issue also at play here.
The DSLRs aren't optimised for video shooting and so they tend to run hot when the mirror's up and they're essentially in live view/video mode.
So the 12 / 20 minute clip limits have to do with that too.

But also:
Looking at the D7000 with its overflow capability, like the EX1/3, there's theoretically no limit to the length of shot that's possible, regardless of file size. With the overflow, as soon as one card gets full, writing switches over to the other card. While that's happening, in theory you could pull the first card, insert a fresh one, and keep going.
In the EX1 or 3 that's exactly what happens, no matter if you have a 2GB card in or a 32GB card in.
You can take one continuous clip that spans several card-loads. But even though, like the EX1, the D7000 has two card capacity, you can't exceed the recording time limit on each clip.

In theory, the same would be possible for a DSLR. However, two things, 1) the sensor heating, as I mentioned above and 2) the fact that they didn't pay royalties for proper AVC aquisitiion (or whatever the video compression system is) means that they've essentially crippled or cut off the maximum recording times to the lengths they are now.

Not that this should be a problem, of course. How many people actually watch single shots that last for 12 minutes without a cut?

C

Perrone Ford November 13th, 2010 10:59 PM

Quote:

Originally Posted by Chris Leong (Post 1587878)
Not that this should be a problem, of course. How many people actually watch single shots that last for 12 minutes without a cut?

C

You ever film a press panel? A speech? A conference presentation? I've filmed all three with no breaks for over 45 minutes. Occasionally over an hour which is why I went tapeless in 2004. MiniDV proved too short for the panels I was assigned to shoot.

Eric Pascarelli November 14th, 2010 06:46 PM

I did an interview with my EX1 that lasted more than three hours. Definitely a shortcoming of DSLRs, that you can't do it.


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