There's been enough dissections on how Canon and Nikon shot themselves in their respective feet by releasing mirrorless systems with only single card slots. Trust Tony and Chelsea Northrup, though, to spice things up a bit with some scientific analysis.
I know that this has been debated ad-nauseam, but I haven't actually seen any proper data on just how often the unspeakable happens. If anyone is a little tight of purse or just on the fence about it all, it helps to have solid figures to guide one in the right direction.
The Northrups conducted a poll among their followers asking them their experiences with memory card failure rates. The poll, consisting of 4,344 people, while not a giant sample size, still seems like a size which one can pull some relevant data out of. And that's one of the things that I think this channel is best at. I always enjoy the Northrup's videos, but I find the more analytical ones to be almost always enlightening with regard to the more technical aspects of photography.
The arguments have gone back and forth over this, even on this website, but it's this kind of analysis that might actually sway people instead of one-off horror stories. I won't spoil the results by repeating them here, so please watch the video and share your thoughts below.
Why is he (or anyone) lumping the Nikon Zs in with the Canon R here? The Nikon Zs use XQD cards, which are far more robust, both physically and in the bus protocol, and are known to fail far, far, FAR less often than SD cards. In fact, Thom Hogan did an informal survey among his colleagues and couldn't find a single instance of an XQD card failure.
Sorry,, that is not the way it works. Two of an inferior SD cards, which have a higher failure rate, if that failure rate is significantly higher than say a XQD card, at some failure rate, will be less reliable than a single XQD card. It is a basic engineering probability problem. An example is airplanes. It used to be that 4 engines were required to fly across the Atlantic. Now, 2 engine airplanes fly across because their 2 engines are just as or more reliable than the previous 4 engine planes.
They can use two now because they can still fly the plane with one, which is the requirement (that it stays in the air). In the old days with the old tech the planes couldn't fly with only one engine due to power and design limitations. Jet engines have always been reliable, because they have to be.
Absolutely correct. People make it far more complicated than it is; failure rates, some cards are more reliable than others, etc. It's not relevant.
The fact is that having a backup is better than no backup. Period. Card failure isn't the ONLY thing that can result in loss of data.
General probability, regardless of your opinion or experience will state having a backup is better than not having one. Use a single card slot, I don't care. Just don't argue against it. Your reason doesn't matter.
I remember my very first wedding (an event that takes around 1-2 hours in total with a peak of critical events lasting for maximum 10 minutes) shooting with a 6D as main camera and the card inside it got corrupted. Oh boy, the chills... Fortunately, my heavy electronics & computer science background kicked in and after 2 long and dizzying days I was able to recover all of the pictures (and more) from the SD card, but that event taught me a very good lesson.
It's not a novelty to get your card corrupted because a filthy data stream was unexpectedly still active at disconnect (the same reason why USB sticks get corrupted sometimes when you don't "safely remove hardware") or god knows what other reasons. But if you expect to shoot events that cannot simply be re-shot, that additional slot is something to consider if you expect to build up some reputation.
Lexar cards are pure rubbish.
It’s amazing. Tony recognizes hateful commenters about his SD card failure opinions and 1 or 2 slot cameras, then quickly makes a new video addressing the issue yet shutting up those who claim the otherwise.
He is efficient, quick and very good on his job. Congratulations to Tony.
Here is some obvious precautions we all can take:
1) Do not take in and out your SD card often. Prefer to use usb cable and keep the card in as much as you can.
2) If you must take the card out, do not use it on multiple devices. Multiple laptops, iPads through adapters.
3) Dedicate SD card per camera. Try not to use the same card in multiple cameras. Especially multiple brands and type of cameras.
4) Do buy 2 card slot cameras. At least for the important shoots configure the slots so you have a back up.
5) Do demand the camera manufacturers to install inbody memory. Either to use for primery or secondary recording. Anybody has heard of a disk failure on iPhones? Less likely.