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UlfLaursen
07-28-2016, 11:18 AM
Hi

i was wondering if I need Lexar 2000X 128 GB to record 4K, or these would be sufficient:

http://www.lexar.com/pro-1000x-sd

what do you guys use?

thanks for any input

Ulf

Barry_Green
07-28-2016, 11:22 AM
The "1000x" and "2000x" are meaningless when it comes to suitability for recording. Those are marketing-speak, not technical specs.

What you need are (at least) UHS-1 U3 cards. The ones you linked to are UHS-2 U3 cards, so yes, they would be plenty sufficient.

UlfLaursen
07-28-2016, 11:25 AM
Thanks Barry - btw. Love your you tube videoes on the DVX200 - thanks for sharing them too!

Ulf

JRJphoto
07-28-2016, 11:43 AM
I am using SanDisk Extreme UHS-I U3 Class 10 cards in SDXC 128, 64 and SDHC 32 GB flavors. Two each SDXC for the DVX200 and one SDHC that is usually inside the stills camera.

UlfLaursen
07-28-2016, 11:48 AM
Thanks Jason :)

MScrip
07-29-2016, 03:01 AM
Hi

i was wondering if I need Lexar 2000X 128 GB to record 4K, or these would be sufficient:

http://www.lexar.com/pro-1000x-sd

what do you guys use?

thanks for any input

Ulf

I can echo the other people here. You don't need those 2000x cards. I've used Lexar 1000x cards for recording 4K in the Panasonic FZ1000. They will work fine in the DVX200 too.

What you're really looking for in any card is the write speed of the card.

Those 1000x SDXC cards claim to support 75MB/s to 80MB/s write speeds.

The DVX200 records 4K at up to 150Mbps... which translates to about 19MB/s

So there's plenty of headroom for writing 4K to those cards.

And when you get back to your computer... the read speed of those cards is fantastic too. With a USB 3.0 UHS-II card reader... you should be able to pull files off the cards approaching their maximum read speed... 150MB/s

I only have a UHS-I card reader... but I can still pull files off at around 90MB/s... (which is still great)

In conclusion... the 1000x cards are fine. There's no need to buy the 2000x cards since the DVX200 wouldn't be able to take advantage of their faster write speed anyway. The only thing you'd gain from the 2000x cards is faster read speed in the computer... but I don't think the extra cost is worth it.

UlfLaursen
07-29-2016, 08:07 AM
Thanks MScrip

i have several modules in this series, on thunderbolt and love it :)

http://www.lexar.com/workflow

Ulf

ericyoung
07-29-2016, 10:21 AM
More specifically it's the SUSTAINED MINIMUM WRITE speed that is important for RECORDING video. This is specified by the U3 designation which means a sustained minimum write speed of 30MB/s (that's MegaBytes).

Barry_Green
07-29-2016, 10:34 AM
More specifically it's the SUSTAINED MINIMUM WRITE speed that is important for RECORDING video. This is specified by the U3 designation which means a sustained minimum write speed of 30MB/s (that's MegaBytes).

Exactly. That's exactly why those naming conventions exist -- because they are guaranteed sustained minimums, which is what the camera needs to know. The 75MBps or 80MBps claim or whatever is, again, marketing-speak; generally the manufacturer will say "up to 75MBps" which is effectively meaningless -- I mean, they're saying "it will be less than 75MBps", which, heck, 3mbps is less than 75MBps, so really, what does that 75MBps figure really mean? Even if it's an average, it's no good -- if the card writes 8,000 MBps for eighty sectors, and then drops down to 6MBps for one sector, and then back up to 900 MBps for the next ten sectors, the card will still fail. Because that one sector where it was below the minimum necessary speed, will cause a failure.

You need a SUSTAINED MINIMUM that is a higher rate than the camera sends data at. And the industry standard for classifying sustained minimum speeds is either "Class" (i.e., Class 10) for SDHC cards, or "U" (i.e., U1, or U3) for SDXC cards. UHS-I U3 is the specification the DVX200 needs to handle 100Mbps or higher footage.

UlfLaursen
07-29-2016, 10:39 AM
Thanks guys - all has been most helpful :)

Ulf

DLD
07-29-2016, 10:46 AM
The "new" ratings for the sustained speeds are V30; V60; V90. All denote Mega Bytes per second (MB/s). V30 should be sufficient for DVX200 but, if someone is using an external recorder with ProRes, then s/he should look for the particular product manufacturer's recommendations.

Barry_Green
07-29-2016, 11:40 AM
Yes, the new V30 designation is supposed to be equivalent to UHS-I U3, which is what the DVX200 requires.
https://www.sdcard.org/press/thoughtleadership/160301SD_March_Thought_Leadership_FINAL_video_spee d_class.html

Eventually they will be transitioning all labeling to the new V6/V10/V30/V60/V90, which is a far more useful indicator than "UHS-1 U3"... but until that transition is complete, folks should be aware that the requirements for the DVX200 can be satisfied by either V30/V60/V90, or by UHS-I U3, or UHS-II U3.

*of course, this whole UHS situation is slightly silly anyway. They used to classify cards by "Class", so Class 2 was 2MBps, Class 4 was 4MBPS, 6=6MBps, 10=10MBps. Then they went for this weird UHS classification, and now they're going back to where they started, but adding a "V" to it. So now C10 is the same as V10, C6 is the same as V6. I guess we'll look back on the whole "UHS" naming phase and wonder what they were thinking, but soon (hopefully) they'll have it sorted out to where it all makes logical sense again.