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The maximum number of images you'll be able to wirelessly transfer at once is 500. This number can vary substantially because of issues such as battery power and signal strength.
Since you're only able to transfer 250 images at once, we recommend limiting the number of images you transfer to 250 or so, then send the next 250 images.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.