For stills I've always had a couple of SanDisk Extreme III 4GB disks. I've never had issues with the cards. Is there anything in particular to look for when dealing with HD in the 7D (Or that people have noticed in their 5Dii)

This page may be of interest:
Levi Buzolic CompactFlash for Canon 5D Mark II Video (http://levibuzolic.com/2009/01/cf-for-canon-5dmk2-video/)

The transfer rate of the 7D is probably very similar to the 5D Mark II

Jason,

I've always used the Extreme III in the 5d2 (video) with no problems. I wouldn't go any slower than that, but I don't think you need to go faster either (unless you have extra cash). Bear in mind that 4gb is only 12 minutes recording time in HD (assuming 7d will be same as 5d), so you'll need a few cards. Currently I use 2x 8gb and 1x 4gb, but will be picking up another 16gb Extreme III, as I'm using the 5d more and more and shooting HDV less. It's a beautiful thing that the media is reusable, but scary in that with HDV tape (even the best ones) are relatively cheap and you can save your master tapes in case of disaster. It's troubling sometimes to re-format CF cards when you've got important footage on there (back-ups to multiple hard drives now).

I and several others on here use Kingston Elite Pro 32 GB 133x CompactFlash Memory Card for video on the 5dmkii. They are cheap and have been very reliable to date. The only negative I haven't been able to quickly take a still pic while video recording.

Does anyone prefer the Extreme IV cards. Do they make a difference?

Peter

I forget where I read it, I think in a CF Card review on B&H, but someone was saying that his Extreme III or equivalent was great except for when taking a still during HD video recording -- that it would cause a bit more of a delay and a few occasional lost frames compared to doing the same with a UDMA-enabled CF card like the Extreme IV, Hoodman Raw, Ridata 32 GB UDMA, etc.

I think I'll have a 16GB super-fast UDMA card or two for my main photo/video cards, and then multiple more affordable 32GB fast cards for extra video shooting in the field, and a UDMA-enabled CF card reader for my MacBook Pro Express Card slot, if there is such a thing, or at least a Firewire UDMA CF card reader (faster real speed than USB 2).

There are now newer and faster cards than the IV

SanDisk | Products | DSLR | SanDisk® Extreme® Pro? CompactFlash® Card (http://www.sandisk.com/products/dslr/sandisk-extreme-pro-compactflash-card.aspx)

Peter

Yes :) ... Just saw the Extreme Pro news on robgalbraith.com -- an excellent pro digiSLR site that also tests CF cards, a MacBook Pro monitors for color accuracy, etc.

Hopefully the not-as-new Extreme IVs and other UDMA cards will drop in price substantially before my mid-October trip to Thailand with my 7D that is on order :)

OK - I need it explained to me like a 4th grader.

As far as we know, will the Extreme III be perfectly fine on the 7D? Is there absolutely any reason to go faster? For example, which of the below would be better:

SanDisk 32 GB Extreme III Compact Flash Memory Card - Pack of 3 for $519.95

or

SanDisk 8 GB Extreme IV Compact Flash Memory Card - Pack of 3 for $299.95

Keeping in mind that switching cards (the time it takes) is not an issue.

For _video_, even the Extreme III's 30MB/s is way more than enough. The 7D is only 40Mb/s (note the lower case b, Megabits vs MegaBytes), which is only 5MB/s.

The main reason for faster CF's is not video, but when you're shooting 8fps of 17mp RAW files. That's 22megs per file, 8 per second or 88megaBytes per second. Now you see why Sandisk came up with the 90MB/s Extreme Pro series.

Bought a pack of 3 SanDisk Extreme III 30MB/s Edition 16GB for 250USD plus 90USD rebate.

OK - I need it explained to me like a 4th grader.

With the right card reader extreme IV will copy to the computer faster. On camera a fast card matter to some still photographers. But not for video, as emptying the buffer is not an issue.

Extreme III is a good conservative choice. But only buy cards that say "30mbs" on the front. These are UDMA. There are older extreme III that are not UDMA.

Tim Smith of Canon specifically recommends using UDMA cards. He said that people have reported glitching or banding when using non-UDMA cards, and that those things just don't happen when using UDMA. He said their speculation is that the codec may be dumbing down the bitrate to accomodate the slower cards, and that when using a UDMA card, such "dumbing down" never needs to happen.

Tim Smith of Canon specifically recommends using UDMA cards. He said that people have reported glitching or banding when using non-UDMA cards, and that those things just don't happen when using UDMA. He said their speculation is that the codec may be dumbing down the bitrate to accomodate the slower cards, and that when using a UDMA card, such "dumbing down" never needs to happen.

I saw the video in which he made that statement. He seems like a very smart man, but how does he as a representative of the company speculate on what "might" be happening. It seems to me a more definite statement is needed-- not the "codec may be dumbing down" . He also made statements about mods to frame rate for the 5D on the chip and other sought after revisions not being possible or feasible. On the other hand, he freely admitted he never thought Canon would even make a change to let the camera go to a manual mode. He seemed to have a lot of experience with the camera-- espeically in the early days before the new firmware, but I am not so sure we can trust his technical pronouncements.

YIKES! ... Was this only with the 7D?
And have any 5DmkII owners experienced anything similar, with the somewhat lower bitrate?

Not that glitches/banding are ever OK in serious usage, but did Smith say how often these things were present and how readily visible they are?

WHY would this happen, when the codec is about 48mBITSsec/6mBYTESsec and Extreme IIIs are 30mBYTESsec and thus should have PLENTY of speed for the 7D's video?!?

Megabits to Megabytes Conversion Calculator (http://www.unitconversion.org/data-storage/megabits-to-megabytes-conversion.html)

Question - I know the speed of the card impacts the time it takes to upload but does it matter for recording video as long as your not experiencing buffer issues? I've been using SanDisk Ultra ll 15MB/S with no issues. They're relatively inexpensive so I'm wondering if there is any reason to buy faster cards. I think the minimum requirement for the 5D is 9MB/S.

I would personally stick with UDMA cards. As Barry Green wrote, Tim Smith of Canon stated that there have been problems with non-UDMA cards.

I've read that with slow cards, video still records, but the encoder's bitrate might adjust downward for slower cards. Sure, you'll still have video, and it might look fine, but you never know if the compression would be better on a faster card.

UDMA is cheap insurance.

I hope I find out that UDMA cards are pricey excess in real life 7D video usage, 'cause the next level down is so much more affordable if you have to load up with big fast cards for a big, long field trip ... but you might be right, we'll see.

As a frequent still shooter, I will make sure my main/primary cards are tough and UDMA, regardless, though.

I've read that with slow cards, video still records, but the encoder's bitrate might adjust downward for slower cards. Sure, you'll still have video, and it might look fine, but you never know if the compression would be better on a faster card.

UDMA is cheap insurance.

I can confirm that this is not true. I've been testing this with my 7D.

With a slower non-UDMA card, the buffer fills - you see a status bar on-screen, and then it simply _stops_ recording when the buffer is full.

Bitrates are running btwn 45-47mbit/s, or 5.75MB/s.

...With a slower non-UDMA card, the buffer fills - you see a status bar on-screen, and then it simply _stops_ recording when the buffer is full...

Well, at least you know when your card isn't fast enough.

I wonder if they changed their approach in the 7D. I've never heard of this behavior in the 5D2.

I can tell you for sure that 4GB 150x cards don't cut it. (got my 7D today) Cuts out after 5 seconds or so of recording.

Going to return the cards I bought and wait until someone comes out with a good, cheap card recommendation that's KNOWN to work with the 7D.

I'm not 100% sure, but I believe that UDMA is the key requirement.

Canon recommends UDMA cards for the 5D2, but non-UDMA cards don't fail hard. (They apparently show artifacts like streaking and might drop frames.)

It seems that the 7D doesn't fail gracefully with non-UDMA cards. A better solution would be to fail gracefully, but to notify users that the card is too slow for optimum use.

... someone was saying that his Extreme III or equivalent was great except for when taking a still during HD video recording -- that it would cause a bit more of a delay and a few occasional lost frames ...That's not a function of the card at all. When taking a still photo during video recording, there will be a 1-sec. freeze frame recorded to video. That's just the way the camera works. Card choice does not affect this.

...I am not so sure we can trust his technical pronouncements.I have known him personally for ten years, so believe me, *I* am sure we can trust his technical pronouncements.

I'm not 100% sure, but I believe that UDMA is the key requirement.Canon USA made this clear to me in November of last year when I was originally briefed on the 5D Mk. II. Perhaps it is my own fault for not clearly emphasizing this enough in our 5D Mk. II forum, but UDMA has *always* been the key requirement in selecting Compact Flash cards for the EOS 5D Mk. II (and now the EOS 7D). Hope this helps,

Picked up this SanDisk 8GB UDMA 400x 60MB/s Compact Flash card yesterday ($120)... I'll let y'all know how it goes.

Just to add that I've use my 7D with several non-UDMA A-Data 16gig and 32gig CF's (A-Data has a UDMA and a regular line, these are the regular type), and they work fine in video mode. They're about 1/2 the speed of my Extreme III's 30MB/s CFs when shooting stills. I also have a 4gig A-Data CF, and that one stops recording in about 5 seconds.

In using non-UDMA cards, I've not notice _any_ streaking or artifacts or drop-frames. 5.75MB/s or 47mbit/s (same bitrate for 720/60p, 1080/24p and 1080/30p) is not very much at all.

Well, at least you know when your card isn't fast enough.




Actually Canon suggests that the processor may cut the data rate on cards sensed as slower. The speaker even suggested that slow cards may cause higher noise.

I'm in the "it's not worth the risk" camp.

I'm not understanding about UDMA cards as being "pricey". What are you guys doing, using cards only once?

Actually Canon suggests that the processor may cut the data rate on cards sensed as slower. The speaker even suggested that slow cards may cause higher noise.

That was for the 5D2, wasn't it? The 7D could be different.

That was for the 5D2, wasn't it? The 7D could be different.

Unless Canon is definite the logical approach is conservative. It's an odd area to go cheap. I'm not even suggesting the best cards are necessary. Just the UDMA cards from the brands that have consistently produced trouble-free memory.
Now if a card has worked well for several hours of shooting and the footage has been edited, that's a pretty good test. But early on I had some 300X cards that showed some buffer filling but didn't quit for a few tapings. But finally I did get a buffer overflow that stopped the recording. There are infrequent but not unexpected conditions in the data flow that are difficult for non-UDMA cards to handle

You have to remember that UDMA CF's are designed more for DSLR's with their "bursty" style of files writes rather than the constant but much lower speed writes of video.

The UDMA spec is old, that's the old ATA/ATAPI standard. Most of us have moved on to SATA drives now. The UDMA spec is only for the _max_ transfer speed of the _interface_, not the actual thru-put of the card. So it's not surprising that Don is running into this problem with his 300x cards. Do you mind letting us know which brand/model they are?

The manual for my Edirol R09 actually recommends not using the fastest SDHC cards available, but sticking with Class 4 instead, citing the "bursty" nature of the faster cards as a reason.

It would be nice if DVInfo could keep a database similar to the Rob Galbraith SD/CF page of which SDHC and CF cards have worked well for video, and which cameras they were tested on.

Just an FYI…

I set my 7D up in the backyard, wide lens, lots of detail, and let it record an 11 minute clip to one of my SanDisk Extreme III 32GB cards. No problems at all, no buffer issues, it just works.

--SM

You have to remember that UDMA CF's are designed more for DSLR's with their "bursty" style of files writes rather than the constant but much lower speed writes of video.

Without a data analyzer, we don't know that the video output isn't bursty. For all we know, the DIGIC writes to RAM and then bursts to the memory between scans.

I'm not saying that I think it's bursty, but we can't assume that it's not.