How to Set the Sony a7R III to Automatically Switch to Memory Card Slot 2 when Slot 1 is Full

By default, the Sony a7r iii doesn’t automatically switch to memory card slot 2 when the card in slot 1 is full. So if you’re getting an error message that there’s no space on the memory card and it’s not automatically switching to the card in slot 2, here’s how to change that.

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Filed Under: Mirrorless Cameras

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The Sony a7R III has two SD memory card slots. You have quite a bit of control over how they’re used. For example, you can prioritize one, designate one for movie files, or set it up to mirror image the files.

They’re the types of things that are pretty standard on top-of-the-line cameras these days, but there was one specific setting on the Sony that caught me by surprise and temporarily halted my shooting while I tried to figure out the solution. It might have been an obvious fix to some shooters, but it wasn’t for me.

I had two memory cards inserted. With 85-megabyte RAW files, filling up memory cards is an occupational hazard with the a7r iii. But after filling up one, I was getting the error message at the top of this page that reads “No space on the memory card. Slot 1.

It’s a showstopper error–while it tells you what the problem is, it’s not the least bit helpful in steering you toward a solution. And yet you can’t keep shooting until you fix it. Sure, you could physically swap out the memory card, but you shouldn’t have to when the camera has two memory cards.

In fact, you don’t have to do that. But the catch is that the default setting on the a7r iii is for it not to roll over to slot 2 when the card in slot 1 is empty. I assumed that it would.

It’s not complicated to change the setting so that it does roll over, but it did initially take me some time on-site scrolling through menu options trying to find where to change the setting. So I’m posting it here in the hope that it helps someone else (and probably me again, next time when I forget).

How to Change the Setting

You can find the relevant menu item on the menu system on the back screen under the general setup tab (the toolbox icon). It’s the sixth page “Setup6”, and the setting you’re looking for is called “Rec. Media Settings.”

Sony a7r iii memory card slots automatic rollover 1

Once you drill down to that, you have some submenu options. Among them is the “Auto Switch Media” option.

By default, it’s off. Switch it to On.

You’ll now have it roll over automatically to Slot 2 when the card in Slot 1 is full.

Sony a7r iii memory card slots automatic rollover 2

As I said, it’s not complicated. But if you’re fumbling around in the menu system trying to find where to change it, hopefully, this might help. I do find it a bit odd that it’s not set to automatically rollover by default and it caught me out the first time, but now I leave it on the automatic switch setting.

Frequently Asked Questions

Can the Sony A7R III use different types of memory cards?

Yes, the Sony A7R III is compatible with SD cards (SDHC/SDXC) and is designed to work best with fast UHS-II SD cards.

If you’re using two memory cards, they do not need to be identical types, brands, or storage capacities (although the latter is useful if you’re using the mirror setting).

What happens if both memory cards are full?

If both memory cards are full, the camera will stop recording and display a warning message. To continue shooting, you’ll need to replace one or both of the full cards with empty cards or delete some files to free up space.

Can I switch between memory cards manually during a shoot?

Yes, you can manually switch between memory cards during a shoot. To do this, go to the ‘Rec. Media Settings’ menu, select ‘Prioritize Rec. Media,’ and choose the desired card slot.

How can I tell which memory card is currently in use?

On the Sony A7R III’s display, you’ll see a small icon indicating which card slot is currently in use. The icon will show either ‘1’ or ‘2,’ representing the respective memory card slots.

David Coleman / Photographer

David Coleman

I'm a professional freelance travel photographer based in Washington DC. Seven continents, up mountains, underwater, and a bunch of places in between. My images have appeared in numerous publications, and you can check out some of my travel photography here. More »