[Rob Davis]

*I mean XAVC (long gop)

What happened to the edit button on this thing?

[Rob Davis]

Bad ProRes file on the timeline? It’s all hvac and h.264 quicktime.

[Rob Davis]

Did the test but same result. Highlights in final XDCAM made in AE had clipped pixels.

Interestingly, at least one of the PNG frame’s highlights was clipped upon immediate import back into Premiere, without XDCAM in the mix. This is happening with multiple formats: Sony XAVC, Gopro h264, Canon h264, etc. I’m going to try upgrading soon (I’m on v9). Hopefully, Adobe will have worked some of these bugs out without introducing too many new ones (like last time I updated).

I’m also hoping they will have addressed the myriad of issues related to the audio track mixer and Media Encoder exports and several other things.

[Rob Davis]

Thanks for your help, Chris.

Here are PNG’s of another example. Just as in the previous case, the ProRes422HQ export is fine but the XDCam EX 1080i60 35mb/s VBR has a few pixels pushing past 100IRE. And like last time, this also happens if I convert the ProRes export to XDCAM in Streamclip, so it isn’t unique to Premiere, I don’t think.

ProRes422 HQ:

XDCAM:

XDCAM (converted in Streamclip from ProRes Export):

I also just encountered another render error that could be related. This section of my audio had a 1-sample spike that didn’t exist on the timeline. And this is rendering in ProRes!

[Rob Davis]

Thanks for your suggestions. To clarify, I only used Streamclip only for a second test after encountering the issue with the initial media encoder export (and also direct export from premiere).

I’ve used LUTS extensively working with LOG footage but haven’t used them much for broadcast workflow color management. Am I correct in understanding I can incorporate a LUT in my Media Encoder export to conform the MPEG2 to Rec.709. Can you elaborate on that? Forgive my naivety on the subject and thanks again!

[Rob Davis]

Another clue:

Now I’m really confused. I tried exporting a ProResHQ version from Premiere (which had correct IRE values) and then converted it to a 35mb/s XDCAM MPEG2 in MPEG Streamclip. I imported that XDCAM version back into Premiere and again, parts of the image were bumped over 100 IRE.

On closer inspection, I can see that random pixels within the highlight areas are responsible for the clipping. These are photos of my Flanders monitor’s LUM color setup to show 0-100 IRE as grey and 100+ as Red. Notice the random red pixels in the closeup of the reflection on the water.

Obviously, I don’t care if these pixels are clipped on broadcast but don’t want to fail QC.

Is this a known issue related to XDCAM? I never noticed a problem before.

[Rob Davis]

Note: This is only happening when I export MPEG2 (though I’m sure I noticed it with another codec), not prores or h264.

[Rob Davis]

Thanks for the reply, Shane. Blackmagic Media Express crashes on my system so I can’t test on that but I’m pretty sure there is something happening on Premiere export. Even when I import the file right back into Premiere I see the highlights bleeding over 100 IRE (see photos).

[Rob Davis]

Update: I did discover a workaround for anyone else having this issue but its a bit of a pain so would still love to know whats going on for future reference.

Here is the workaround:
1) Import the clip again (as if its a new clip) but don’t delete the original problematic clip
2) Go to the first frame of each instance of the clip in your timeline
3) Copy the start timecode
4) Open the new clip and paste the start time code to match the in point
5) Go back and select the bad clip in the timeline and go to Clip> Replace with Clip> From Source Monitor, Match Frame
6) Repeat for all other problematic clips on timeline
7)Once everything is replaced you can delete the bad clip

[Rob Davis]

That’s a good point. Would you say that’s the best option at the moment?

I didn’t really notice a performance dropoff with OpenCL until I started dealing with some AVCHD clips or something like that, which required more rendering.