SDHC substitute for SxS cards

[Greg Boston]

Originally Posted by Steven Thomas

The door issue is not a show stopper. Afterall, when using Sony's new video capture drive you have to leave the door open.

And if you're just using one card, you can put it in the front slot and slide the access door partially closed over slot 2.

-gb-

[Steven Thomas]

Thanks Greg. That's what I'm doing.

I have (yet) another expresscard coming next week to try. It has the spring type recessed cavity for media. I'm hoping it works like the Kensington.

[Steven Thomas]

Matthew at "another" forum sparked this next test:

Ok..
I performed a quick test for S&Q.

Camera set to 720 24P S&Q ON at 40 FPS. (Almost half speed) I had no errors, but I only ran if for 5 minutes or so.
It failed when S&Q was set to 45.

During playback, since the resultant overcrank S&Q file maintains the 35mbps (40mbps peak), the S&Q record data rate must maintain a linear relationship; therefore, overcranking at 40FPS at 24FPS: 40FPS / 24FPS = ~ 1.66X

Data rate linear relationship:
The base recording data rate (HQ in this case 35mbps (peak at 40mbps) So,
40mbps x 1.66 = 66.4 mbps. Which is the same as 8.3MB/s

Bear in mind longer tests would need to be taken, but based on the S&Q mode overcranking a 24P mode at 40 FPS without failing it appears the Kensington 7-in-1 Expresscard adaptor and Extreme III 30MB/s SDHC is capable of 8.3MB/s.

Since the EX HQ modes top out at (40mbps/8)= 5MB/s and this combo is capable of 8.3MB/s, this leaves 40% headroom while running all HQ modes. This is good news and explains why this combo works well!


Although 8.3MB/s is good news, you can't help but wonder why not a higher data rate.
I've clocked the SDHC card and it over 15MB/s read and write sustained.

I now REALLY believe the bootleneck is how Sony is offering the data rate over USB at this port. It for sure explains why their own drive will not support S&Q mode.

[Ola Christoffersson]

Originally Posted by Steven Thomas

Day three testing the expresscard adaptor / Extreme SDHC in the EX1:

1, Kensington 7-in-1 Media Reader $ 36 (USD)
1, SanDisk Extreme III 16GB 30MB/s version $129 (USD)

No issues recording or playing any of the HQ or SP modes (No S&Q)

Today I tried the above combo but with the 8GB-card. So far it has been performing exactly like the SxS-cards with exception of S&Q (which I have not tried).
First I filled the card with random short and long clips here at the office and then I went out filming. I threw away bad takes just like I usually do and no issues!
Filled up the card and I am copying it to my PC now. It is much slower copying though but for 1/8:th of the price of a SxS-card I don't mind!

Has anyone had any errors using the Sandisk Extreme III? I am tempted to start using it in production.

[Paul Kellett]

Has anyone had clips spanning cards yet ?
Do the spanning also work ok, as with sxs cards ?
Either sandisk to sony sxs or sandisk to sandisk ?

Paul.

[Paul Kellett]

[QUOTE=Ola Christoffersson;940820]Filled up the card and I am copying it to my PC now. It is much slower copying though but for 1/8:th of the price of a SxS-card I don't mind!

QUOTE]

I presume you're plugging the sd card into a normal sd card slot on your pc, i wonder what transfer speed can be expected if the sd card was left in the sxs>sd adaptor then that was plugged into a sxs slot on a pc ?

Does a normal card reader slot connect inside the pc via the usb header ? If so then you'll get the usb bottle neck.

Paul.

[Nick Schale]

Wow... keep up the great work guys!!!

[Steven Thomas]

Based on the read specs direct using my reader and the new Extreme 16GB SDHC (I clocked at reading 20MB/s), it should transfer to your computer at 1.2GB/minute.

[Steven Thomas]

Originally Posted by Ola Christoffersson

Has anyone had any errors using the Sandisk Extreme III? I am tempted to start using it in production.

Ola,
I'm on day 5 and have yet to have an error. I've been trying to force erros with quick start and stops and also filling the media right to the end.... No issues!

As I mentioned in my last post, I estimated this combo alows 40% of data rate headroom running HQ (35mbps).

[Alister Chapman]

I've cycled through a few 8Gb Transcend Class 6 cards with no errors during normal use. I get downloads to my Mac that are about 30% slower than SxS, but it's still a lot faster than real time. One of the great things is being able to use a cheap SD to USB adapter to bring in footage to my MacPro.

[Keith Moreau]

Originally Posted by Paul Kellett

Has anyone had clips spanning cards yet ?
Do the spanning also work ok, as with sxs cards ?
Either sandisk to sony sxs or sandisk to sandisk ?

Paul.

I tried spanning from an 8GB SxS in slot A to a 16GB Sandisk Extreme III with the Kensington adapter yesterday with one long 1.5 hour clip (actually Parrots in our town of Brisbane, the same parrots as the ones in "The Wild Parrots of Telegraph Hill" by Judy Irving). I used 1080 30P mode.

To add more complexity into the mix I took the SDHC card out, which had about 11GB in it and transferred it to a little SDHC to Hard disk stand alone media transfer unit I had. This unit is pretty slow, took about 20-30 minutes to transfer from the Sandisk Extreme III SDHC to the stand alone hard disk unit, but it completed. I didn't have to do this, I could have just put the Kensington adapter/Sandisk Extreme III into my Macbook pro (which I've done before), but I wanted to see if this transfer workflow would work. (and it did).

Then I connected the stand-alone hard disk unit via USB to my Mac, and it had the BPAV folder. I copied that over to my Mac, that took about 18 minutes.

I used XDCam transfer 2.7 to add both the Card A expresscard BPAV folder and the Sandisk Extreme BPAV folder (which had gone through a roundabout transfer to my Mac) and imported the clips folders both folders.

The resultant Quicktime file of about 1.5 hours played perfectly. So I would say this worked. I guess next would be Sandisk Extreme III in card A and B and do the spanning thing, but so far seems to work. Now if we could get that darn SxS door to close...

Using just the Expresscard slot in my Macbookpro to copy, and the Sandisk Extreme/Kensington combo, it seems to transfer at about 50%-75% of the of the Sony SxS cards -about 1GB per minute.

[Steven Thomas]

You're right Keith, by my earlier speed tests and calculations, the new Extreme III reads at around 20MB/s = 1.2GB/minute

[Steven Thomas]

BTW,
I wrote to Kensington tech support and asked if the Expresscard 7-in-1 was capable of 32GB SDHC (I believe it will since 16GB cards work), and I also asked if they had an equivalent expresscard reader with the low profile "spring type" media card slot.

His reply was that the expresscard reader was not SDHC capable...

LOL, apparently he did not read the whole mesage I sent. I mentioned we were using 16GB SDHC with no problems.

Unreal...

Having said that, I can not find any technical spec that shows it works with SDHC.
But, we all know it is SDHC capable..

[Alex Raskin]

Is this of interest?

Lexar intros 16GB high-speed SD card | Crave, the gadget blog - CNET

[Steven Thomas]

Alex, that card is actually 2 to 3 times slower than the new SanDisk Extreme III 16GB 30MB/s version.