Here's what I've learned so far, but I'm still not able to get ATV to playback a slo-mo clip directly from the 5s. I did get it to work via iMovie - but what a pain! Instructions below - it shouldn't have to be this complicated of a work flow.
It appears that legacy devices may not be able to play slo-mo. Why is not clear but my guess is 120fps is not supported. We saw this in older generation ATV's when itunes could play a 1080p movie, but the ATV could not 'see' that movie until new ATV hardware was released with faster processors and iTunes was updated.
A key discovery for me was that Photostream supports a shared slo-mo clip (at least when played back from a 5, 5s or latest iPad, all with iOS7). Others subscribed to my Photostream could see the slo-mo effect.
My devices are:
- iphone 5s
- ipad (latest) with iOS7
- Desktop: Mac Pro, OS X 10.8.5, Aperture, FCP X, iMovie
- ATV: current
A slo-mo clip recorded on the 5s plays back as expected, but only through the camera/photos app. iPhoto and iMovie do not retain the slo-mo effect on the 5s.
If I Airdrop the clip to another 5s, 5, or iPad, slo-mo is retained. And iMovie on iPad will recognize the slo-mo.
If I Airplay to ATV, it is a black screen. Audio is present. No video, but the progress bar suggests it is streaming video.
I can share the clip to Photostream, and slo-mo is retained if played back on 5, 5s or iPad. It does not appear on ATV photostream.
Aperture does not see the clip in Photostream.
FCP X can import the movie from the 5s. It does not retain slo-mo. It chokes in playback and needs optimization to playback without dropped frames (also a function of my older CPU performance).
If I use the Image Capture OSX app to copy the clip to my Mac Pro, it does not retain slo-mo (quicktime/itunes)
The only way I can view slo-mo in ATV is by using iMovie as follows:
1) Airdrop the clip to iPad
2) Import to iMovie on Ipad and confirm slo-mo is working.
3) Goto iMovie project screen and Share the project to iTunes
4) Connect the iPad to your desktop/laptop
5) Select your iPad from the Sidebar in iTunes
6) Choose "Apps"
7) On the App screen, scroll down to "File Sharing" in the main body of the Apps window
8) Choose iMovie. You should see the iPad imovie clip in the right pane under iMovie Documents.
9) Click "Save to..." at the bottom and save to a folder you'll remember.
10) Go to that folder and open the iMovie mobile project. It should launch iMovie (OS X) and import it.
11) Play the clip in iMovie on your desktop/laptop to confirm slo-mo is retained.
12) You should be able to Share from iMovie (on OS X) to your favorite destination, including iTunes. That will allow you to view on ATV.
Be aware that the shared clip is 29.97 fps with the slo-mo effect preserved.
Again, I can't get the above to work if I go directly from the 5s to OS X iMovie. I could only make it work via my iPad.
This convoluted work flow is clearly not how it should be, but if you want a work around, this should help you until a fix is released.