Thunderbolt Display as AV Output?

I am using an iMac 5k with two Apple Thunderbolt displays.

Is their anyway to configure (or trick) FCPx into seeing one of my thunderbolt display using AV Output (so I can use it as a viewing monitor as I edit)? If not, thats a stupefying oversight on Apple's part - as Premiere does it without a problem. Can't really be HDMI only can it?

You'll need something like a Blackmagic UltraStudio Mini Monitor to get A/V output from your iMac. Only certain Macs with built-in HDMI can do A/V output directly. Here's what Apple has to say about this.

Note that a Thunderbolt to HDMI adapter will NOT work. It will only work as a second display, not as a viewing monitor.

Send feedback to Apple about this and maybe they'll fix it some day. A/V output should definitely work out of the box for any Mac. As you say, Premiere can do it, so should FCP X.

Before getting a UltraStudio MiniMonitor (or equivalent), beware that FCP X does not work perfectly with this type of solution. The issue is that the content on the A/V monitor will not be in sync with the viewer on your main computer screen. The A/V output is maybe 4-5 frames behind, which means that audio will be noticeably out of sync when looking at one of the monitors. Not great.
This is not an issue with the hardware, it's on Apple to make FCP X work better.

"Note that a Thunderbolt to HDMI adapter will NOT work. It will only work as a second display, not as a viewing monitor."

Well actually a thunderbolt to HDMI - works just fine with AV Output on my iMac. So yes despite what Apple say it does work.

Its just I want to use my thunderbolt monitor to view my video output as that's on my desk.

Pretty infuriating really. I used to be FCPX's biggest advocate but its stuff like this that is making Premiere my editor of choice these days (never thought I'd ever say that a few years ago).

I'll second that a "thunderbolt to HDMI" will work as an AV output with FCPX.

It's even nice that you can also mouse over to that screen and swipe it out as an additional desktop at your whim.

As for making your "thunderbolt monitor" work, I'm not sure if you can. the closest I could think of is just setting it so your viewer shows up on it. not quite the same, (ie, not full screen) but you have the added bonus of having scopes on them, and if you have your viewer to 100% you still get pixel for pixel readout if you're using HD fotage.

All the best,

I wonder when they added the Thunderbolt->HDMI output capability, I have completely missed it in the release notes. It makes it even more baffling that simple Thunderbolt output is a no go.
Thanks for the heads up, I look forward to trying it out!

FCP X seems very particular about when it allows A/V output. I have an older mini DisplayPort -> HDMI adapter that in general works just fine with the physically identical Thunderbolt port. The system recognizes the HDMI monitor and can output to it, but FCP X can't use it. If I switch the adapter to a Thunderbolt -> HDMI it shows up in FCP X. But only if the monitor is set to 1920x1080, other resolutions do not work. I'm guessing that changing the resolution of one of your monitors to 1920x1080 won't work either?

These very specific restrictions to A/V output are odd, especially since they do not seem to be properly documented. Intuitively, A/V output should be allowed to any connected monitor, I can't see any reason why it shouldn't be.

You might want to check some of these:

www.fcp.co/forum/4-final-cut-pro-x-fcpx/...n-2013-imac-it-works

www.fcp.co/fcp-forum/4-final-cut-pro-x-f...from-fcpx-on-imac-5k

support.apple.com/en-us/HT200185

I don't use HDMI for monitoring, but here's a comment from someone who uses 3 displays including a 4K TV: an Apple LED Cinema Display (24"), a Planar 27" PXL2790MW hooked up via Thunderbolt to Display Port, and a Seiki 39" UHD TV (via HDMI).

"FCPX on the late 2013 mac pro or 15" Retina MBP supports broadcast monitoring (HD, and 4K) via HDMI right out of the computer - in "A/V Output" mode the HDMI panel will show up if turned on. It won't however work with Final Cut Pro X to monitor in 4K UNLESS you turn the HiDPI "retina" scaling off first. That's easy enough to do and is a quick click of a button in display preferences. In fact FCPX won't show any video out on the panel in A/V Output unless the monitor is shown at its native resolution."

- Ronny