SDHC vs. CF

I always have both CF and SD cards in my 7D2, but always write to the SD card and never (except by accident) to the CF card. The reason is that the CF is an old Transcend card, whereas the SD is a new SanDisk Extreme Pro. I'm not going to update the CF because it is a dying breed. The SanDisk Pro is plenty fast for me in burst mode.

The CF card is in the camera just as a backup.

On older cameras it might be better to use CF for the faster speeds offered. For example my 60D could only write at up to around 30-45MB/s to its SD card even if a faster one was installed. I think it'd be safe to assume cameras of similar age would be the same speed, and so CF would have faster options. My current 7DII can fully utilise the 95MB/s SD cards I purchased for the 60D (before I realised they were a waste on the 60D), and if I was to get CF I could get slightly faster at near double the price. Why bother? I'll just stick with SD. My laptop and other systems only have SD readers built in which makes things easier too.

SD gives me the convenience AND the speed. With newer cameras they're the way to go IMHO. Only go CF if you're using them on an older camera.

Faster cards than what the camera supports are not always a complete loss, assuming they have superior read speeds and use a card reader that will support them.

The difference really isn't all that huge, but being able to move images from the card to a storage drive a little faster can be a nice bonus in some cases. I don't really see a difference when taking photos with my newer set of CF cards and a few of the older slower ones that I have, but it does shave a little time off loading stuff to the computer afterwards by way of an external card reader. And when it comes to loading up a weekend worth of sports photos it can add up to a few minutes.

CF is not only on its way out, it is actually at the end of its life already. It is such a niche market at this point. The selling price is so high that manufacturers can afford to do lot of testing and screen for CF. Basically with he column and selling price, cost to make is not an issue. On the other hand, SD is commodity, the cost to manufacture matters a lot, thus the quality can be compromise. For this reason, the reliability of CF is higher than SD by a big margin. But it is no way to say SD isn't reliable.

Having the above said, if I have option to choose between CF and SD today, I will definitely go with SD. With cost of CF and the nearly end of life form factor, I just won't spend money on them

There was a big deal about this when the camera was released, but performance-wise in a 5D3 you're much better off with the CF card. Just put it in burst mode and try it for yourself - the SD is much slower because it doesn't support UHS. This is true also if you're writing to both cards at the same time (which sucks if you like to back up in-camera). The camera slows to the speed of the slowest card.

I've had SD cards fall apart on me, so I much prefer CF cards for their robust build and slightly larger size. The pins are a non-issue as long as your card reader, camera, etc. has enough depth between the opening for the card and the pins. I've only bent pins on (cheap) readers with very shallow CF slots.

Josh_30 wrote in post #17429396
There was a big deal about this when the camera was released, but performance-wise in a 5D3 you're much better off with the CF card. Just put it in burst mode and try it for yourself - the SD is much slower because it doesn't support UHS.

SD cards can support the UHS standard, specifically the SD Association states "The UHS Speed Classes defined by the SD Association are UHS Speed Class 1 (U1) and UHS Speed Class 3 (U3)." The card should have the letter "U" with a 1 or 3 in it.

Whether it makes a difference is undetermined.

cerett wrote in post #17382137
Beyond the obvious difference in physical size, is there any advantage of one over the other if your camera takes both? Is SDHC a safe storage media?

It depends on your camera.
5D3 is slower on SD cards.

They keep trying to make the CF go away, but then they up the pixel count and the video frame rates making the parallel I/O of the CF cards all that much more attractive than the constrictive serial data flow in SD cards. The memory tests of Rob Galbraith used to prove this over and over, but then he stopped running and publishing test results. SD adopts faster standards, but then CF comes along and ups theirs, too -- and one is hard pressed to make a one-bit wide SD datastream as efficient in moving data as an 8-bit wide data stream.

The industry should recognize the inherent strengths of CF vs. SD, and make the devices FIT where each is used to its best advantage! SD when you want cheaper storage, CF when you want speedier data flow!

Wilt wrote in post #17440991
They keep trying to make the CF go away, but then they up the pixel count and the video frame rates making the parallel I/O of the CF cards all that much more attractive than the constrictive serial data flow in SD cards. The memory tests of Rob Galbraith used to prove this over and over, but then he stopped running and publishing test results. SD adopts faster standards, but then CF comes along and ups theirs, too -- and one is hard pressed to make a one-bit wide SD datastream as efficient in moving data as an 8-bit wide data stream.

CF is faster, but not by much, and in many cases SD is fast enough. For me fast SDs meet my requirements when doing bursts photographing birds. So I use SD (I keep old CF cards as backup).

No point in spending money on speed you never use.

How do you explain the 3:1 speed differentials seen in camera tests with both CF and SD memory in the same camera?

http://www.cameramemor​yspeed.com …st-sd-cf-card-comparison/
showed 27 to 37% speed advantage for CF in the 7DII, admittedly at $39 price disadvantage. But if you are waiting for the buffer to empty all the time during hired jobs, a few bucks is worthwhile so you miss less of the action!

Wilt wrote in post #17441074
How do you explain the 3:1 speed differentials seen in camera tests with both CF and SD memory in the same camera?

http://www.cameramemor​yspeed.com …st-sd-cf-card-comparison/
showed 27 to 37% speed advantage for CF in the 7DII, admittedly at $39 price disadvantage. But if you are waiting for the buffer to empty all the time during hired jobs, a few bucks is worthwhile so you miss less of the action!

So CF is 30% faster. I use the Sandisk Extreme Pro SD. It is cheap and very fast and all I need.

John from PA wrote in post #17440769
SD cards can support the UHS standard, specifically the SD Association states "The UHS Speed Classes defined by the SD Association are UHS Speed Class 1 (U1) and UHS Speed Class 3 (U3)." The card should have the letter "U" with a 1 or 3 in it.

Whether it makes a difference is undetermined.

You are both correct. SD card itself can be UHS-1 interface. But the host, could be a card reader or camera slot, also need to support UHS-1 in order to operate at this mode. 5D3's SD slow does NOT support UHS-1. Its interface only support up to 25MB/s. So no matter how fast of a card you put in, you can't go above 25MB/s. In reality, with interface overhead, the limite is more like 18-19.

To be technically currect, the proper designation should be UHS-1 Speed Class 3. UHS-1 standard has interface speed up to 104MB/s. There is a UHS-II stardard which can do to 3xxMB/s.

From what I was reading. The reader makes a difference as well. This is the link I was reading from. LINK~~ http://blog.photoshelt​er.com …e-why-you-should-upgrade/