If you paid attention to the introduction of Canon's and Nikon's first full-frame DSLRs – the EOS R, Z6 and Z7 – you would have noticed that some people were rather unhappy that they only had one card slot – an SD card Slot for the Canon and an XQD slot for the Nikons instead of dual memory card slots. So, let's find out what the big deal was.
Professional and prosumer cameras traditionally come with two card slots
Canon and Nikon have traditionally included two card slots in their prosumer and professional offerings. Usually it was an SD card slot and a CF or other faster card slot, but as SD card speeds have increased, this has changed a bit. Sony mirrorless SLR cameras use all two regular SD card slots.
You can use two slots in several ways:
- You can put RAW files on one card and JPEGs on another card. That way, you'll have all the data, but you'll also have smaller photos that you can quickly edit on the go.
- You can put RAW files on both cards, giving you a perfect backup if something happens to a card. This is the most popular use.
- You can first shoot one card and then the next, which gives you more space. As prices for SD cards have dropped, this is far from popular. Now, when people want more space, they go with bigger cards.
Shooting to dual-card slots, however, was never without its downsides. Since the camera had to write on two cards at the same time (and one was often slower), she was able to slow down the speed with which the camera could take several photos. They were wedding and landscape photographers, for whom data integrity was more important than the burst speed they used. Sports or wildlife photographers were often unable to do that.
Nikon has apparently addressed this with the Z6 and Z7: They have used a single XQD slot that offers a faster standard than SD cards. This means that the cameras ̵
Has only one card slot that is so insecure
The whole uproar is
- That many people rely on two card slots.
- That a single card slot is so much more insecure than two.
I suppose Canon and Nikon did their research and found that the vast majority of people who bought their top-end cameras did not use or at least did not trust duplicate card slots. The amateur photography market dwarfs the professional market
The second issue is a bit more thorny. Memory cards can and may fail. It's easy to find horror stories from photographers who lose amazing images that cost a lot of time and money to create. It's stupid to think SD cards are 100% reliable. However, the likelihood that you have a problem with your SD cards when using high quality cards and treating them well is tiny. It's like a reverse lottery: Someone will lose data, but the likelihood that you are you is next to nothing.
For photographers who need data security, wedding photographers are by far the biggest one's big day – then dual-card slots are a must and Canon, and Nikon's decision is a nightmare. After all, wedding photographers are one of the largest groups of professionals.
For everyone else it's probably not that big a deal. I shoot at dual-card slots because it's a good idea, but it's not critical to my workflow. With a single card slot, I would risk a bit more, but realistically, I tend to lose pictures because my camera is stolen, as an SD card fails.
And really, that's the decision that all face now. Canon and Nikon have decided that a single card slot is good enough and most people are likely to. A few more photographers will lose images if they decide to become mirrorless, but the vast majority will not notice the change. In addition, Sony still makes cameras with two card slots – and who knows, the uproar might be enough to get Canon and Nikon to add them in the second generation.