[Shupienis]

Hello fellow K-3 III users and Linux users! As we all know the world runs on Windows™ and stuff that works there does not necessarily support Linux. It is often easy for the experienced user to fix these little issues and enjoy our familiar crash-free, marketing-free use of our favorite cameras using our favorite operating system.

The issue: While using Linux, Rapid Photo Downloader and other software applications fail to connect to your shiny new K3 Mark III via the USB-3/USB-C connection.

Symptoms: Programs attempting to access the photos on the K-3 III via the USB-3 connection fail and report "unable to read device" or "device not found" and the like. If you are using a USB-2 port on your computer, the problem might not occur, but does occur when you use your computer's USB-3 or USB-C ports.

More information: It's a permission thing. The K-3 III registers itself as a USB device which can be found in /dev/bus/usb. The plug-and-play automatically assigned permissions for that device, when connected via USB-3, restrict reading and writing to that device to only the "root" user, and members of the "audio" group.

The Solution: from the command line, type:

Code:

sudo adduser <yourID> audio

After the command has completed successfully, log out and log back in. You should now be able to connect to your K-3 III via the USB 3 cable at full USB-C speed!

[Not a Number]

Thank you for the tip.

I don't use Linux and know next to nothing about it. The K-3 mark III use MTP (Media Transfer Protocol) with the USB connection so I would guess using the MTP mount options would work as well.

[Shupienis]

Thank you for the tip.

I don't use Linux and know next to nothing about it. The K-3 mark III use MTP (Media Transfer Protocol) with the USB connection so I would guess using the MTP mount options would work as well.

You are correct—the only protocol available in the K-3 III for file transfer is MTP, and that is what my software will use for the K-3 III.

The "UNIX way" involves low-level services (or "daemons") as an interface layer between physical devices and applications. Every program that wants to download files from the camera via a USB cable goes through the "gphoto2" service, which negotiates with each USB device to discover and use the appropriate file transfer protocol. In practice, I simultaneously download photos from both cards in my K-1 (via PTP orMTP for videos), both cards in my K-3 III (via MTP), my iPhone (via file system mount), and sometimes both cards in my Nikon (via PTP or file system mount). Because of the middle-ware server, I don't know and don't have to care which protocol is being used for which device, and they can all dump their new photos as quickly as possible.

Simultaneously, as in "all at the same time".

It makes me happy!!!

[stevebrot]

More information: It's a permission thing. The K-3 III registers itself as a USB device which can be found in /dev/bus/usb. The plug-and-play automatically assigned permissions for that device, when connected via USB-3, restrict reading and writing to that device to only the "root" user, and members of the "audio" group.

Now you've got me curious. I have never tried to mount my K-3 to my Linux box. Maybe it is time to give it a try!

Simultaneously, as in "all at the same time".

Multiplexed, as in "it only looks that way".


Steve

[jcr]

I feel like I should point out that (at least on my 2015 MacBook Pro Retina) the USB-C–to–USB-A cable included with the K-3 mark III was only connecting at USB2 speeds (480mb/s). So I tried a different cable and got the full USB3 "SuperSpeed" (5gb/s).

I don't know if the cable included with my camera was defective, or not certified for USB3 speeds and only really meant for charging, or what. But if you are noticing slower than expected transfer speeds from your K-3iii, check the interface speed and maybe try a different cable.

[beachgardener]

Nice one, thanks all for the information here.