I’ve had a couple of people contact me regarding selecting a SDHC card to use with their Sony EX1 cameras and SDHC adaptors. While SDHC is not a replacement for SxS cards in critical applications they do have their uses where SxS may be impractical (e.g for handing over to a client at the end of a shoot).
Up until a few months ago the SDHC card of choice was produced by Transcend. Their cards seemed to be both fast enough and reliable enough to be able to cope with the 35 meg per second + overheads that the EX1 requires to reliably record.
However from mid summer onwards I began to notice that some of the Transcend SDHC 16 meg cards we were purchasing seemed to be slower than our older cards. Some cards were taking as long as 10 seconds to finish writing. I wasn’t the only one to notice this either as some of the users at DVinfo.net began to complain of slower performance and even failed recordings.
In short if you buy a Transcend card today although it may be within the Class 6 specification, it may well not be reliable in your EX1. For whatever reason the performance of the cards has changed for the EX1.
All is not lost however. After some research I found that ATP ProMax SDHC cards seemed to be a potential replacement. I’ve now purchased four of these cards and although more expensive than the Transcend cards they seem to be up to the job. I’ve run the cards through tests in the office and in the field and as far as I can see they appear to be the best match available in the UK at the moment.
The ATP ProMax SDHC card seems to be a good match for the Sony EX1
However these is some bad news….. Whereas everyone and their dog will sell you a Transcend card at knock down prices the ATP cards are somewhat harder to locate in the UK. After clearing out Amazon of the only 2 cards they had, I had to order 2 more cards from the USA. The good news is that after a few weeks of being out of stock, Amazon UK seem to have some more cards in….(deep breath) a steep £44.85 each, nearly twice what we’ve been paying for the equivalent Transcend.
ATP Pro 16gb SHDC card on Amazon
I’m yet to find any other UK supplier. One other company did list them on their website but don’t have any stock. If anyone reading this finds another UK supplier then please let me know and I’ll post it here.
There are arguements raging on the various forums about the merits of SxS v SDHC. SDHC has its uses but you should always throughly test cards before you use them in a live video production situation with your EX1. There is an inherent risk with any recording media be it film being accidentally exposed or tape jamming up. Contrary to popular belief solid state media is not infallible. Have confidence in your media before you set out on a shoot.
Critically you must not press record before the red light above the card has cleared. I always have the song “Red Light Spells Danger” by Billy Ocean in my head during those 5 or so seconds it takes to clear. When the light goes green I then always count to three before pressing record again. That way you can be sure of avoiding “media restore” errors.
SDHC adaptors are another tool in your video production arsenal. However it remains to be seen what the impact of Sony introducing their own adaptors will be and what impact any of the rumoured firmware updates will have on the existing SDHC solutions.
This blog entry is provided for informational purposes for the EX1 user community only. Users purchasing and using SDHC do so entirely at their own risk.
#1 by Jeff Scott at November 16th, 2009
Thanks for the info. You mention you do thorough testing on all your SDHC cards. Could you explain your testing process, please? I recently had a Sandisk card crap out on me. Thanks! Jeff
#2 by admin at November 16th, 2009
This isn’t fool proof or scientific but is meant to simulate what happens in real life. I sometimes point the EX1 at a TV with some fast moving action for this.
First of all I fill the card with clips of between 5 seconds and 15 minutes. It’s important to ensure you have something moving in the viewfinder as the EX1 uses a VBR codec therefore the datarate can change.
I also record some overcranked material at 40fps (again with moving material in the viewfinder) in with these clips. I know some cards will go higher than 40fps but again it’s a VBR codec. You might be able to happily overcrank to 45fps with the lens cap on, but it’s no test.
During the first test keep an eye on how long the red light takes to clear each time. Notice any variation? Is it consistently approx 5 seconds or less? Does it sometimes take longer?
When the card is full, transfer the footage in. Does it all transfer and play OK? No glitches? Does the transfer slow down at any point or is it consistent? What we’re looking for is consistency across the card.
When that’s done I format the card in the camera and then do a couple of run throughs just filling the card with clips of between 15-30 minutes. Then I transfer the footage in and check it.
By then I’ve done 3 run throughs and to my mind any problems should have appeared.
I used to run the media through various check disk utilities but since one faulty card made it past this test I abandoned it. It appears that some cards aren’t faulty as such, but just have slight variations in write speed.
This testing isn’t foolproof but at least should give you confidence that you’ve tried a card before you take it into the field. The key thing is ensuring it takes approx 5 seconds to clear the red light. What I noticed with one of my faulty Transcends was that if the first and second clip on the card were a certain length red light would take up to 10 seconds to clear and could also trigger a media restore with the loss of the clip.
#3 by Jeff Scott at November 16th, 2009
Thanks for the explanation! The Sandisk that went bad didn’t kill all the clips, just the first one. It was an important interview. I’ve tried restoring the media numerous times. The five other clips play fine. The bad mp4 will play for :30sec before triggering an error message in the cam. I’ve tried copying the suspect file on PCs and Macs with no luck. I keep getting error messages. Any advice to save/repair the clip OR should I move into the acceptance phase and plan for a proper burial? Thanks! Jeff
#4 by admin at November 17th, 2009
I had joy with XDCAM Transfer. I clipped around the offending broken section and managed to recover most of the video apart from a few minutes around where it went wrong.
However I was then stuck with MP4 files. However this piece of software allowed me to insert mp4 files onto the Final Cut timeline:
http://calibratedsoftware.com/MP4EXImport_Mac.asp
Restoring the media doesn’t usually help. All the camera appears to do is rewrite the XML files the EX1 saves.
Another important point is that if you have a faulty card, write protect it straight away. MacOS and other OS’s like to write stuff to any media inserted. No guarantee this won’t make things worse.
#5 by admin at November 17th, 2009
Sorry, I meant Clip Browser. Clip Browser will often play “broken” clips and will let you clip out the sections that are OK.