Blackmagic Forum

Hi all,

I'm having trouble getting Davinci to export a mov with reliable colours

I've been through a lot of forum posts and tutorial videos but I can't find a way to get the same colours in an export. Is there something I'm missing. Any help would be greatly appreciated.

I'm using OSX 10.14 (Mojave) with Davinci Resolve 15.1.1.005 and exporting to a Quicktime mov.

Thanks,
Pete

Load the exported video back in Resolve, if it looks ok in Resolve the problem is your environment. Perhaps your video player uses a different gamma.

I’ve spent (wasted) hours upon hours on this. You are correct. The colours look one way in resolve and once exported to QT they look like crap. It loses contrast and saturation. However, if you download a version of VLC and playback the same film through that then it will look very similar to how it looked in resolve. If you load the same QT file to vimeo and view through Firefox or Safari then it’s starts to look more like it did in Resolve. If you view it through Chrome then it gets even worse. An iPad will look a more contrasty than my desktop computer and so on...

Solution? Well you can go and spend a lot of money on proper reference monitor and get it all set up properly and at least then you know you are correcting to a known value/set of parameters and that’s how professional colour graders work. Or, if your work is mostly going to be viewed online (not broadcast) then grade something on your calibrated monitor using your scopes, upload it, view across multiple devices, different computer monitors, iPads, iPhones etc and see how it looks then tweak as you think to get the best average across all the devices. After awhile, from experience you’ll get a feel for how something should look. I did a days training with a professional colour grader and he said he would grade to his reference monitor and then would have various adjustments he would apply to the entire clip depending on where it would end up being seen. He had one recipe for YouTube, another for Vimeo etc.

The sound engineer I work with does something similar when he does my audio if he knows something is only being viewed on line. He’ll balance everything using his studio monitors then replay it back on everything from his phone and to small crappy computer speakers and then make little tweaks from there if need be.

I know this doesn’t sound very scientific but when there are so many different ways that your film can be viewed you are never going to be able to get it to look the same on everyone device.




Sent from my iPad using Tapatalk

Cool thanks, Cary! Just brought it back into Resolve and it looks way better.
I'm just using standard quicktime to playback the file and I'm guessing my clients will be too, is there a way to make that playback correctly?

Oh, just saw your post Randy, that sounds slightly depressing. The thing I don't get is that it looks different on the same machine, I'd expect a little shift on another device.

Quicktime uses a different gamma. It's been like that since forever. Even Youtube uses a different gamma when it reencodes our videos compared to the original, or to Vimeo. Some apps just rather use 2.2 over 2.4 gamma, and vice versa. Something we have to live with...

Eugenia Loli wrote:Even Youtube uses a different gamma when it reencodes our videos compared to the original, or to Vimeo.

No, there is no gamma shift during re-encoding on YouTube and Vimeo.

Ughh, I remember having this problem almost 10 years ago, thought it might have been fixed by now.
I remember we had some workaround for it, I think if encoded with xh264 (or something similar) it seemed to fix it, but it doesn't seem you can do that from Resolve.

I just tried the upload to Vimeo and I can confirm, it looks like crap there too.

Peter Leary wrote:I just tried the upload to Vimeo and I can confirm, it looks like crap there too.

It means your system is not set up correctly for viewing.

You might want to encode an SMTE ARIB chart and upload it to Vimeo and YouTube.

Ahh I figured something out! Since everything was consistently broken outside of Resolve I went hunting inside the preferences and found this -

With that on, the viewer matches the other exports.

One problem now is that my 3d renders look different in Houdini to Resolve. So I guess I have to figure out how to match that in the 3d render...

BTW, as far as I know, for h264 you need to be in video mode, not full (as for your screenshot)

Yes, you should upload to Vimeo and YouTube using video levels, not full range.

Hmm, I thought display profiles would override everything (kinda like night mode).
So do applications have to opt in to this adjustment? It seems that Houdini and Resolve are in matched (when Resolve is set to not use the profile).

Peter Leary wrote:Hmm, I thought display profiles would override everything (kinda like night mode).
So do applications have to opt in to this adjustment? It seems that Houdini and Resolve are in matched (when Resolve is set to not use the profile).

if a video is 422 encoded the standard is video range. You're forcing the wrong setting there.

Oh, I ended up going with the Vimeo preset and got the same result.
I’m going to tackle it a bit more over the weekend. I have heard the Mac profile stuff is a bit of a pain. If I find anything useful I’ll post it.

again, if you're doing any h264 that is not 444 (not sure if it is even possible) you must set for either auto or video range.

waltervolpatto wrote:again, if you're doing any h264 that is not 444 (not sure if it is even possible) you must set for either auto or video range.

Yes, 444 is possible with H.264.

You could, for instance, encode lossless 444 with long GOP by using the -pix_fmt yuv444p10le and -crf 0 in ffmpeg.

Cary Knoop wrote:

waltervolpatto wrote:again, if you're doing any h264 that is not 444 (not sure if it is even possible) you must set for either auto or video range.

Yes, 444 is possible with H.264.

You could, for instance, encode lossless 444 with long GOP by using the -pix_fmt yuv444p10le and -crf 0 in ffmpeg.

Not sure you can do that from resolve.....

waltervolpatto wrote:

Cary Knoop wrote:

waltervolpatto wrote:again, if you're doing any h264 that is not 444 (not sure if it is even possible) you must set for either auto or video range.

Yes, 444 is possible with H.264.

You could, for instance, encode lossless 444 with long GOP by using the -pix_fmt yuv444p10le and -crf 0 in ffmpeg.

Not sure you can do that from resolve.....

Oh no, Resolve's H.264 is rather limited and glitchy.

It's better to export to an intermediate file (ProRes, DNxHx, Cineform) and then generate using x264.

Cary Knoop wrote:Oh no, Resolve's H.264 is rather limited and glitchy.

It's better to export to an intermediate file (ProRes, DNxHx, Cineform) and then generate using x264.

Just as a side note. I've been thinking about the whole internal vs external H264 encoding 'dilemma' again of late, and of all of the forum discussions that have speculated on 'what could be' if Resolve supported FFMPEG export.

For some years now I've been using Pegasys (TMPGEnc) SmartRender 5 (and before that, version 4) for cut-editing of native HD-AVC footage. Excellent product. It uses a licensed (and configurable) x264 encoder implementation and is one of the very few so called 'smart cutters' that does frame-accurate smart-rendering properly. Pegasys have always been strict on standards compliance. Resolve even accepts the trimmed/joined files without question, so that's saying something.

Perusing their product page, as I was the other day, I saw that they also have AVC (and MPEG-2) export plugins for Edius Pro and Premiere Pro:

http://tmpgenc.pegasys-inc.com/en/product/e9mp4.html

http://tmpgenc.pegasys-inc.com/en/product/tppm4.html

Not being an Edius or PP user, I haven't tested either myself.

But I wonder if BMD might give thought to getting together with Pegasys and developing a similar plug-in for Resolve ? Feasibly it could be the ideal solution. Those who are content with the internal H264 encoder could stick with it. Those who yearn for integrated x264 export could buy the plugin, and we could dispense with this need to export to a bulky and lossy 422 intermediate. Maybe x265 export also. Of course it would need to be supported by both the Studio and Free versions.

Just a thought, but a quite reasonable one at that.

I think some older version of Fusion had a simple FFmpeg hack, just set an environment variable to FFmpeg = 'ffmpeg executable folder'.

It should be easy to provide such an interface on export in Resolve, all you need is a codec selection FFmpeg and a text field for command line options.. Resolve could use a 10 or 12 bit output stream (FFmpeg, unfortunately, does not currently support float pixel formats).

Actually, I have not bothered to try but I think if you render to a named pipe (which looks like a file) you could use an intermediate program at the other end of the pipe to directly stream to FFmpeg.

Dunno. There's been lots of discussion over the past few years speculating on how Resolve could pipe out to FFMPEG, but it's not come to anything. If the issue on BMD's part is not wanting to open the flood gates for encoding to non-proprietary codec implementations (I'm thinking ProRes of course) maybe a dedicated plugin like this would be the better solution......for Windows users, that is.