SD cards for high bitrate footage, discussion

dbwolfe

Active member
I have a 32GB SanDisk Extreme Class 10 SDHC card that says 30MB/s right on it and I'm able to cause the recording to fail with the tester13 'C' settings for 44mbit. I'm really pushing the codec by using a a high shutter speed (1/500) SH mode (720p60) and whipping the camera around. I'm sticking with the 'B' 36mbit settings for now as I haven't had any failures.
 
that says 30MB/s right on it
Be aware that the "30MB/s" statement is pure horsecrap. As is all other statements of "266x" and "300x" and "133x". It's meaningless.

On an SDHC card, the "Class" designation is the only one that counts, because that is a *guaranteed minimum* write speed. The "30MB/s" and "133x" stuff is marketing-speak only, and it usually refers to the "maximum" speed of the card. Which is just pointless. Maximum potential theoretical "in the perfect case" ratings, are pie-in-the-sky. What counts is the minimum guaranteed speed.

On a Class 10 card, you should be able to go to 80 megabits, less overhead (if any).
 
I have a 32GB SanDisk Extreme Class 10 SDHC card that says 30MB/s right on it and I'm able to cause the recording to fail with the tester13 'C' settings for 44mbit. I'm really pushing the codec by using a a high shutter speed (1/500) SH mode (720p60) and whipping the camera around. I'm sticking with the 'B' 36mbit settings for now as I haven't had any failures.

Likes tester13 said - it seems it's not the card write speeds that are the bottleneck, it might be a combination of software/hardware in camera.
I've been shooting on "D" settings writing to A-data class 6 16GB-ers all day yesterday (generally considered budget SDHC cards) and didn't have any issues. I guess I was getting lucky.
 
Be aware that the "30MB/s" statement is pure horsecrap. As is all other statements of "266x" and "300x" and "133x". It's meaningless.

On an SDHC card, the "Class" designation is the only one that counts, because that is a *guaranteed minimum* write speed. The "30MB/s" and "133x" stuff is marketing-speak only, and it usually refers to the "maximum" speed of the card. Which is just pointless. Maximum potential theoretical "in the perfect case" ratings, are pie-in-the-sky. What counts is the minimum guaranteed speed.

On a Class 10 card, you should be able to go to 80 megabits, less overhead (if any).

Likes tester13 said - it seems it's not the card write speeds that are the bottleneck, it might be a combination of software/hardware in camera.
I've been shooting on "D" settings writing to A-data class 6 16GB-ers all day yesterday (generally considered budget SDHC cards) and didn't have any issues. I guess I was getting lucky.

BTW, just wanted to mention that A-Data Class 10 cards are now hitting the shelves at $22 ~ $28 (USD) for an 8GB card and right around $50 for the 16GB ones. I bought two 8GB ones yesterday for $28 ea. - I was thinking of offering to supply them here for DU members only but when I looked around that was also a common price in the US so - just a little heads up... Class 10 cards are cheap now! (If they weren't before.)
 
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BTW, just wanted to mention that A-Data Class 10 cards are now hitting the shelves at $22 ~ $28 (USD) for an 8GB card and right around $50 for the 16GB ones. I bought two 8GB ones yesterday for $28 - I was thinking of offering to supply them here for DU members only but when I looked around that was also a common price in the US so - just a little heads up... Class 10 cards are cheap now! (If they weren't before.)

That worries me. Are you sure they're Class 10? I dunno how to confirm but these days people can label whatever they want.

I'mma go with overpriced Sandisks to be sure.
 
That worries me. Are you sure they're Class 10? I dunno how to confirm but these days people can label whatever they want.

I'mma go with overpriced Sandisks to be sure.

Those A-Data cards have very bad reviews on Amazon.

Naw, put your worries to rest. And please... Amazon reviews? Oh my....

Anyway, here's what we're talking about:

I've already removed the (impossible to open) plastic outer shell but this is what you get for your twenty bucks. I have 12 A-Data CF cards mixed with a bunch of Sandisk cards and they've always been just fine. <shrug> Anyways, I'm not trying to promote any brands or anything but if you're in the market for inexpensive class 10 cards here ya go. These are not to be confused with the "Calss 10 Turbo" cards from A-Data though. http://www.hitechreview.com/cameras/a-data-unveils-turbo-series-sdhc-class-10-memory-card/13170/ - whatever the differences might be.


EDIT1:

I just tested the card and the results are in. I used the GH1 camera as a card reader to level the playing field a little bit:

Write File Size: 2,445,121,268
Write Time: 7min 11sec.
Speed in MB/s: 5.673
Speed in mb/s: 45.385

Read File Size: 2,445,121,268
Read Time: 4min 39sec
Speed in MB/s: 8.764
Speed in mb/s: 70.111​

AJA, and SpeedTools QuickBench confirmed nearly identical results. I'm not sure if this is good or bad though. I'm a CF man... ;)

EDIT2:
OOps, And after unplugging 5 other USB devices I get:

Read Speed: 9.6 MB/s, 76.8 mb/s

Write Speed: 7.6 MB/s, 60.8 mb/s

Sorry for the bad testing conditions!
 
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SD cards for high bitrate footage, discussion

We discuss any SD card related questions, card brands, etc, only in this topic.
 
Could there be a performance difference between 4GB, 8GB, 16GB, and 32GB cards in the same brand, series, and class? I've been using 4GB so I can back up each card to DVD, but thinking the higher bitrate will lower recording time I'm not thinking of getting 16GB or 32GB cards and backing up to portable USB drives. Any thoughts?
 
That's what I asked in another thread. I would definitely want to know how the top SDHC cards from Panasonic and Sandisk compare.


Dbwolfe, It's good that you started this thread.
 
I've mentioned elsewhere that my Transcend 16gb Class 6 cards couldn't handle MJPEG for more than a few seconds, but I remembered I also have an 8gb Kingston Class 6 and I can report it handles 50mbps 1080p MJPEG just fine.
 
I've mentioned elsewhere that my Transcend 16gb Class 6 cards couldn't handle MJPEG for more than a few seconds, but I remembered I also have an 8gb Kingston Class 6 and I can report it handles 50mbps 1080p MJPEG just fine.


Did you push the Kingstons and test a higher bitrate to see what the threshold is? 75mbps or higher?
 
> Camera Expert <

I actually didn't start this thread. I think Barry Green started it using my comment from another thread as the starting point. so the credit goes to Barry, good idea since the new higher bitrates will definitely be dependent on specific cards. I only use SanDisk and Panasonic myself.
 
Just done some tests with the following settings in ptool3:

Native 24p/25p
Video Buffer 84,000,000
Video Bitrate Adj 60,000,000
Overall Bitrate Adj 56,000,000
Limiting Bitrate Adj 60,000,000


Camera settings: AVCHD FHD


I did some "Samurai swinging sword of death" pans on two different cards.

Transcend 16GB class 6 - result "motion was cancelled due to writing limitation of the card". This also seemed to cause a corruption of the card which locked up the gh-thirteen. Deleting the files from the card (via another device) fixed it.

Transcend 8GB class 10 - success! A good two minutes of wild pans over lots of detailed scenery and it didn't miss a beat. Playback through camera was perfect too.

As the Transcend class 10 cards seem to be pretty cheap (around half the price of a similar Panny) I'm going to grab a 16GB version and hope it's as good as their 8GB.
 
> Camera Expert <

I actually didn't start this thread. I think Barry Green started it using my comment from another thread as the starting point. so the credit goes to Barry, good idea since the new higher bitrates will definitely be dependent on specific cards. I only use SanDisk and Panasonic myself.
This is the part the bugs me a little. I have an important shoot next week dealing with a couple of famous individuals and I'm dying to try it out but the thought of my PNY class 4 or Transcend class 6 card stop writing in the middle of something important is nerve racking. Maybe my lost Sandisk class 6 card will show up before then.

I really don't want to have to buy a new card but learning what will be the best until that day comes will be a good thing if I do decide to blow a lot of money.
 
Happened to me today. Tried to shoot MJPEG off the EOSHD settings for 50 mBit. I'm getting 30-35 Mbit had a one gig card class 4, worked ok, has a class 6 16gb (transcend) worked just fine. No errors. Checking to see if the class 6 card wrote faster, still haven't compared.

Off to buy a card now and try a class 10 for the first time.

I'm back to thinking how to go from 30p to 25p again though:)

Anyway, this is about cards, I'll post up in a coupla days what happened off each class 4/class 6 class/10, but till now with the 4 and the 6 no issues no freezing no nothing. smooth as heck.

Oh and the footage, even at 30 mBit is mad. mad crazy clean. Shingles and fences and water and leaves yay.
 
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