Using second SD in A7iii reduces write speed

[Mikehhh]

Still working how to move my Nikon workflow over to Sony.

A gripe I'm having is the SD backup in camera.

I have an UHS2 card in slot 1. UHS1 in slot 2.

They write and clear the buffer at the exact same rate.

I did a little test and filled the buffer (about 55 compressed raw shots) and it took around 36 seconds to dump to both cards. And I could see on screen both cards dumped at the same rate.

Taking slot 2 card out, leaving just the uhs2 card. 60 shots cleared in 24 seconds.

So....I just wasted money on uhs 2 cards or am I missing something.

I'd have thought the slot 2 dump would just happen in the back ground. Maybe grabbing from slot 1 so the buffer can just clear quickly.

[IamNic]

Hello @Mikehhh,

the question I ask myself now is if the data transfer is slower because two cards get written to simultaniously OR because the writespeed from the camera is limited by the slowest card.

If the former is the case, even a second UHS2 card wouldn't make anything faster, if the latter is the case, you could easily test it by just having the UHS1 card in the primary slot and doing the same test you did with the UHS2 card.

At least from my point of view that would be the easiest way to see which of the two options is the case.

- Nic

[ThorEgil]

Writing to slot 2 by reading from slot 1 would beat the purpose of dual cards. If card 1 one breaks down you will have nothing.

[IamNic]

Hello @ThorEgil,

I don't quite get what your reply has to do with the query of @Mikehhh...

- Nic

[ThorEgil]

@IamNic

My comment was to the last sentence in the opening post.

[IamNic]

Hello @ThorEgil,

thanks for the clarification, now I understand, thank you.

- Nic