is there a render crash log?

Hello,
I'm pretty new to DaVinci Resolve and have perhaps missed this one, but is there a way of knowing why DaVinci Resolve failed to export/render a project ?

I'm running draft exports to preview a 20 minute film and during the export (often around 8%) Resolve crashes and the export fails.
I've deduced that it's probably something to do with the Magic Masks I've applied. I discovered that some tracking overexposed pages/books need to be re-tracking each time I open the project.

But is there a way to know which clip failed the export?
I feel like I'm missing one of the masks or something because even after re-tracking the masks in question (faces seem to stick; just the books/open pages are a problem), exports often crash.

I unticked my UI Setting Workspace Option "Stop renders when frame of clip cannot be processed" to bypass a "faulty" clip, but the export only succeeds every other/third time I try.

Any thoughts are appreciated...
Does Resolve have a crash log for failed renders.
Is there a way to see all Magic Masks I'm using accross a timeline?

Thanks!

PS I'm trying to export Sony A7RII footage optimized in DNxHR to Quicktime H.264 NVIDIA 1920X1080.

[Peter Chamberlain]

Likely running out of resources. Try rendering to DNx first.

I'm trying to export Sony A7RII footage optimized in DNxHR to Quicktime H.264 NVIDIA 1920X1080.

A cheap workaround: what if you export your project to DNxHR HD, check to verify that file is OK, then pull that file back into Resolve (or the 3rd-party program of your choice) and convert that to H.264?

Is there a reason why you have to export to Quicktime H.264? You may get better results exporting as MP4 H.264. (Either Quicktime or MP4 is just a container.)

Hello Peter and Marc,

No way to pin point the clip that's causing the problem uh...

Thank you for your suggestions. I'm a little slow in responding because I am unable to work on this project during the day.

Is there a reason why you have to export to Quicktime H.264? You may get better results exporting as MP4 H.264. (Either Quicktime or MP4 is just a container.)

I did some work with a seasoned editor and he always used Quicktime... then again, he was on a Mac.
I tried rendering with an MP4 container, but unsuccessfully.

I read today that exporting to the same disk that has the original footage could cause bottlenecks, so I tried to export to an external SSD.

My current set up is as follows:
c drive - DaVinci Resolve
d drive 2TB - original footage
e drive 2TB - cache / optimized media

Only I have about 700GB of footage and 1.8TB or cache! So I've been using the d drive for miscellaneous.

I also disabled all the timelines I am not currently using.
I'm not in front of my computer during the render but when I return Resolve has been closed and the export folder has a corrupt MP4/MOV in it. Render reads Remaining: e.g. 8 or 25% but has stopped.

Likely running out of resources. Try rendering to DNx first.

Pardon my ignorance, do you recommend this before or after grading?
i.e. I've currently got a draft grade on my video.
I export using Quicktime DNxHR 444 12-bit into a single clip
And then convert to H.264

I know I haven't shot in Camera RAW but does changing codecs multiple times alter the editability/colors of the footage?

I'll try the DNx workaround and let you know how it goes.

Thanks for your time.

Update on my attempts:
Exporting Quicktime DNxHR 444 12bit with color grade and magic masks crashed as well.
Is the idea to bypass the grade for export?

Update on my attempts: Exporting Quicktime DNxHR 444 12bit with color grade and magic masks crashed as well. Is the idea to bypass the grade for export?

Why would you use DNxHR 444? If you're starting with H.264, there isn't enough information in there to warrant 444. You could use DNxHR SQX and be just fine.

What if you tried that and then slowed the render speed down to 10fps on the Deliver page? Maybe that would be less stressful for your system.

What if you tried that and then slowed the render speed down to 10fps on the Deliver page? Maybe that would be less stressful for your system.

Hello Marc,

Appologies for the late reply.
Again, I will open with, "I'm pretty new to DR" but I'm confused, your suggestion to rendering down to 10fps... where are you finding the 10fps. I'm limited to my timeline fps or standard frame rates (24, 25, 30, etc....). Also, are you suggesting this to use as proxies? Because, I thought that was the whole idea behind Optimized Media, and ultimately, for render it's reading off of original footage.

Understandably, my GPU is maxing out during the process...
Is your suggestion that I transcode all my clips to DNxHR SQ before starting work?

Marc suggested you reduce the render speed (i.e. the load on your machine), not your playback. You'll find that in the Deliver page under File -> Render speed.

And then, if your machine can't handle H.264 so well, you may want to render your whole footage to DNxHR HQX 10 bit or Cineform YUV 10 bit and compress from that with HandBrake (free).

I'd suggest to cover some of the basic training which BM is offering for free:
https://www.blackmagicdesign.com/produc ... e/training

Forgive me, but I'm under the impression you try to fly a Triple Seven, but are familiar with a Cessna only

Right, only the RENDER speed, not the framerate (FPS). Render speed is just "the time it will take to render this timeline," as opposed to "the run time of this timeline."

Thank you Uli and Marc for your replies, and Uli for clarifying where I didn't understand.

I'd suggest to cover some of the basic training which BM is offering for free:
https://www.blackmagicdesign.com/produc ... e/training

Thanks for this. I have already gone through the ones that seemed more pertinent to the work/time I am on, but unfortunately, I find that all the basic training I've been finding including these offered by BM are pretty simplistic when it comes to rendering. None of them give any suggestions on troubleshooting when Render doesn't run perfect.

Forgive me, but I'm under the impression you try to fly a Triple Seven, but are familiar with a Cessna only

My brother's a pilot and currently flies the triple 7... and he started on a Cessna, so I consider myself on the right course

My brother's a pilot and currently flies the triple 7... and he started on a Cessna, so I consider myself on the right course

Well, seems you just need to follow his example

I found three main reasons for failed renders from my experience:

1. Clips with hidden defects or too demanding effects on them. This is the typical case if renders always fail at the same spot. A Render in place may help, but sometimes the clip is just bad. Try a fresh copy.

2. Overloading the GPU by rendering plus encoding to a GOP codec at the same time. In this case it would help to encode to an easier codec when rendering and later compress (for which I'd suggest HandBrake).

3. General overloading of the system. This happens more regularly on laptops, but can hit a desktop too if the power supply is not dimensioned generously, the thermal paste is drying up or the machine is getting very dusty. It can result in thermal throttling or a complete crash. In such cases Marc's suggestion should help.