After years of resisting the impulse, I finally broke down and got a smartphone, mainly to make traveling a bit easier. Now I can better handle airline and hotel booking and car rental more easily in airports and on the road. One of the reasons I wanted a "smart phone" was so that I wouldn't have to pack my 12 year old DSLR camera and lenses on every trip where I might want photos. I won't go into how I ended up with an iPhone SE, but that is what I have. So now I have to live with the iPhone's quirks. One of the hurdles I had to overcome was getting photos off the phone and onto my Linux Mint v18.2 desktop machine for editing and archiving.
The first thing I tried was connecting the iPhone to my Linux desktop via the supplied Lightning-USB cable. Mint sees and mounts the camera as a USB storage device *but* can't "see" any content (appears empty). Caja recognizes the device as an iPhone and offers to open "Pix" to retrieve media from it. Great, but ... Pix can't see anything either. Bummer. Next, what will my wife's iMac do with a connected iPhone?
On the Mac, the iPhone is recognized but is not treated as a normal storage device, so the file manager again "sees" nothing. So, I tried launching the "Photos" program standard with MacOS and viola!; it can see and import the content. Once in the Photos database, the pics can be exported so they can be moved/copied anywhere needed. But that is sub-optimal since that requires the use of my wife's computer and an import and export operation before the pics can get to the intended destination. On the iPhone I can sync the pics to my iCloud account where I can download the pics via a web browser. But that means uploading and downloading every image (each image is ~1.5MB) and takes time and bandwidth. Again sub-optimal. Just to be complete I tried connecting the iPhone to my Chromebook, expecting the same behavior I had with Mint. But no! It automatically mounted the iPhone and can access the photo directories directly. I already have a userland file system utilizing SFTP (file transfer over SSH) over the home network that allows me to mount my home directory of my desktop machine onto the Chromebook, so I can directly copy the pics from the iPhone to Mint via the Chromebook.
My goal was to not store photos on the iPhone, just keep them there until they can be transferred to my desktop machine for curation. I also wanted to avoid dependence on the Internet for transport and also avoid storing the pics on iCloud. I can send pics via email directly from the iPhone, but that isn't suitable for bulk transfer. So, while it would have been better if Mint could deal with the iPhone directly at least I have an acceptable pathway for transfer. Who would have guessed that the least powerful platform of the three (Chromebook) would be the one most capable of performing this task?
I see evidence that in the past "Pix" was able to transfer media files from the iPhone, but I think later versions of iOS have become more restrictive. As recently as June 2016 it appears that "ifuse" could be used directly to perform this task as described here:
http://www.dedoimedo.com/computers/linux-iphone-6.html
I don't like the fact that Apple conspires to keep users in their walled garden. Only through the use of Apple's "Photos" (or worse, iTunes) program can photos be managed locally and the path to Apple's iCloud is the path of least resistance.
I do hope that there will be an update to Pix or some similar open-source tool that will make life easier but at least I can work with what I have. I did search the web for Ubuntu-iPhone tools and saw the evidence that in the past transfer was possible via Pix and Shotwell. In 2017 I am left with three ways to transfer my pictures:
1. Chromebook via SFTP or sneaker net (SD card or USB stick)
2. MacOS Photos program with SCP or sneaker net
3. iPhone to iCloud and web browser
Update: 9 June 2018
It turns out that I needed Linux kernel 4.15.x in order to import iPhone photos via "Shotwell". I recently got a new System76 "Galago Pro" laptop with Ubuntu 18.04 LTS, which comes with kernel 4.15.x and viola, I can now import those photos without any of the trouble I had previously. When the next LTS of Mint is released (this summer), it too should be able to perform this trick on my desktop as well.
