The higher compression in new media formats Apple added in iOS 11 can nearly double the amount of photos and video you can store when you take pictures and shoot movies on your iPhone or iPad.
However, using HEIF (High Efficiency Image File Format) and HEVC (High Efficiency Video Coding) becomes a problem if you haven’t installed macOS 10.13 High Sierra or later. Earlier versions of Photos and macOS lack support for those two compressed formats.
While many people update all their Apple hardware around the same time, it’s not possible for everyone, such as folks running Macs that don’t meet the latest system requirements. A Macworld reader found a problem in transferring images from an iPhone with iOS 11 or later installed (she didn’t specify exactly) and macOS 10.12 Sierra or earlier. She received the extremely helpful message that the “operation couldn’t be completed” with the error code “com.apple.ImageCaptureCore error -9937.” (Is it really too much to ask to have human-readable error codes this many decades into the home-computing revolution?)
If you see this error, it’s highly likely your iPhone or iPad is set to capture images in HEIF and HEVC, but your Mac can’t import them into Photos—or iPhoto, for that matter.
Check your camera settings in Settings > Camera > Formats. If it’s set to High Efficiency, then the newer compressed formats are in use; Most Compatible, and the iPhone uses JPEG and H.264 video. (Technically, HEVC is H.265 video, where the previous flavor is the more widely supported H.264 encoding; both are packaged into a MOV file by iOS, iPadOS, and macOS, which is a generic video package format, rather than an encoding type.)
If you have High Efficiency enabled, a Mac with Sierra or earlier installed can’t import the images without conversion. However, in Settings > Photos the Transfer to Mac or PC option can be set to Automatic, and an iPhone or iPad should export them in a readable format when your Mac tries to import them, bypassing the compatibility issue. That doesn’t always seem to work.
You should be able to switch to Image Capture on your Mac, import the incompatible files, and then use a conversion tool, like iMazing HEIC Converter (free) for images, which runs on macOS 10.9 and later, and the free VLC, which lets you open and convert HEVC files.
The other possibility is that while you’re capturing images and videos in the compatible, older formats, your phone or tablet is exporting the wrong format. In that case, again go to Settings > Photos and change the transfer setting to Original and try again. For some reason, that fixes the import problem for some people, even though it seems counter-intuitive.
This Mac 911 article is in response to a question submitted by Macworld reader Nichole.
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