Premiere exports my camera footage but not my iphone footage when put together

[firegoddess]

Hello,

I am having an issue when I try to export my footage in Premiere Pro.

I have exported videos from my Sony a6400 camera before and it has worked just fine. 

I have also exported videos from my iPhone 11 and it has worked just fine. 

I export footage from both devices into .mp4 files 

But when I try to combine footage from both my camera and my iPhone into 1 .mp4 file it isn't working. 

My video is basically all camera footage until about the last 20 seconds where I used iPhone footage. 

What happens when I export is that it gets stuck at about "23 seconds left", but when I go to the folder where the file is supposed to be exporting to, the video is already there. But when I click into the video, all of the footage is there except the very end where my iPhone footage should be. 

I don't know if this is because of different fps, or perhaps that I'm combining .mp4 and .mov footage and trying to export both to .mp4, or something else. I also just switched over to a Macbook Pro with the M1 Pro chip, so I'm not sure if that has anything to do with it. I was able to install Adobe just fine and use it after I installed the latest Rosetta ...

For reference I was shooting at:

4K at 60 fps on my iPhone 

XAVC S 4K  (30 P 100 M) on my Sony

*If this isn't the information you need to help me solve this issue, please let me know. I'm clearly a novice.

Thanks in advance!

[Peru Bob · Accepted solution]

Please use the free MediaInfo and post a screenshot of the properties of your iPhone footage in tree view:
https://mediaarea.net/en/MediaInfo

Many users are having issues with VFR. If the file is variable frame rate, use Handbrake to convert to constant frame rate:
https://handbrake.fr/downloads.php
Here is a tutorial:
https://www.youtube.com/watch?time_continue=34&v=xlvxgVREX-Y

Shutter Encoder may also be used to convert to Constant Frame Rate:
https://www.shutterencoder.com/en/

[firegoddess]

Hi, @Peru Bob thanks so much for this information!

It was definitely the VFR that needed to be converted to a constant frame rate. I downloaded Handbrake, followed the tutorial you provided, and that did the trick!

[Phillip Harvey]

If you're using Hardware Encoding you can try switching to Software Encoding for your H264 export.