Hi Gunther,

Your latest pro tip youtube video has come close to convincing me to change my rendering workflow to an all-LRT solution (away from using raws to render directly in AE and, sometimes, AME).

But I'm having a lot of trouble getting the TIFFs that are coming out of LR to match the video file that LRT produces. I'm sure that the fault is mine, and something is set up incorrectly, but I am having trouble figuring out what that is.

fyi: I am rendering max resolution, max colour-depth master files (to act as source files for editing/stock). I want them to be as lossless as possible (so that I can permanently archive my RAW files), thus my LRT export settings:
Codec: Prores
Output Size: Source
Colour Sampling: 444
Quality: ultra high
Gamut: BT.2020
Video Levels: full range

My setup and software versions:
M1 Mac Mini (Big Sur OSX 11.5.2)
My system is colour managed, and I have the correct screen profile .icc file loaded into LRT (I know that's only for previews, but I thought I'd mention it)
LR Classic 10.4
LRT Pro 5.6.3 (build 717)
Camera Raw 13.4
AE 18.4.1 (build 4) Colour management is on, Project Working Space is Rec2020 GAMMA2.4

1st attached image: in Photoshop: what a TIFF out of LR (using LRT export) looks like (this is a cropped sRGB JPEG version of a high contrast area, it's close enough to the TIFF to be a good example)
2nd attached image: LR export screen
3rd: LRT export screen
4th: 1st frame of final movie in AE (this is an 8-bit PNG screenshot with embedded profile, but the shift from the original AE screen is minimal).

Note: I'm only using AE to show the movie frame because it is colour managed, so the last screenshot is an accurate representation of the quite large colour and gamma difference between the TIFF that LR produced, and the movie that LRT produced (lost of detail in the brighter areas of the movie is particularly concerning).

Can you tell me where am I going wrong?

Could it be your image viewer that displays the TIFF without profile applied? Those Tiffs are intermediaries, not meant for direct viewing - they come in Rec2020 color space, which not all image viewers can interpret (it's a video color space).
If the colors of the rendered video displayed in a fully color managed video editor match the colors in Lightroom closely, everything is alright!

This post was last modified: 2021-10-18, 01:10 by chasg.

Hi Gunther, thanks for your reply.

I'm viewing the TIFFs in Photoshop and LightRoom, they look the same in each program. They also look identical to the raws in LR (to my eye, I can't see a shift in colour or exposure when I flip quickly between the two versions).

Regardless, the final render from LRT has blown-out highlights, and a (slight) colour shift, compared to the edited raws in LR. Rendering the same sequence from the raws in After Effects gives perfect highlights (when compared to the originals in LR), but a noticeable magenta-ish colour shift. This shift I'd like to avoid, by using LRT (and its faster renderer), but the blown highlights in the final movies problem is a problem :-(

To sum up: I render out of LR, and the final movie from LRT has blown highlights (when viewed in AfterEffects) vs the raws in LR.

Any ideas? Could it be an M1 Mac or OSX Big Sur problem? Or perhaps it's a _me_ problem (though I don't think of myself as a beginner, having put over 1500 sequences through LRT since version 3).

This post was last modified: 2021-10-20, 01:08 by Gunther.

If you experience a change in contrast it might be a limited/legal vs. full range issue. Try the opposite setting when rendering in LRT - some programs don't interpret the flags correctly and then display wrong contrasts.

Always keep in mind that Photos and Videos live in different color spaces. This topic is extremely complex and there are so many variables involved - especially if you leave the sRGB/Rec.709 world and render in Rec.2020.

Rec.709 and "Legal Range" is the default which most of the programs should interpret correctly.

All good advice, and much appreciated.

Before I do the further testing (thanks for the suggestions), I'm thinking maybe I'm approaching my problem incorrectly. May I ask:

In what format would _you_ create a master file?

In the photo world, I would create a 16-bit uncompressed TIFF, which has the maximal info, with no loss, of any edits to the original photo. What is the equivalent for a timelapse video?

I do this so I don't have to keep my raws available for further renders. A 35GB master file is a lot easier to work with than a thousand raws every time :-)

I've made the (possibly incorrect) assumption that highest quality settings at every stage is the way to go. For rendering in LRT, this means Prores444, Ultra High Quality, 444, rec2020, full range video levels (and similar settings in AE or AME).

I know that a rec709 file is "good enough" for most needs, but, for those times when it's not, then I want to have that highest possible quality master file ready for use.

*****

Just fyi: This "highlights blown out" mismatch between the edited raws (in LR), the rendered TIFFs (via LRT) and the rendered prores4444 file (from LRT) _does not_ happen when I render via AfterEffects (rec2020 gamma 2.4) or Adobe Media Encoder (AME forces rec709). I do get slight colour shifts when rendering from AE and AME, unfortunately, which is why I'd really like to solve this rendering problem with LRT.

I checked my results in applications that I would have thought would be aware of the colour spaces of the results. Photoshop for TIFFs, premiere/AE for rendered movies (and _also_ for the TIFFs, which look identical to the view of the same TIFFs in photoshop, so photoshop must be aware of the colour space these files carry).

I never throw my Raws away. They are the masters. No 16 bit TIFF can substitute a raw. Apart from that the TIFF files are much bigger. If you want to save something, save the Raws + XMPs. Those you can always reedit and also take profit in the future from improvements to the Raw Converter and of course also LRTimelapse.
Personally, I do all my Color and Contrast Editing in LR/LRT, export via LRTExport as 8 bit (in rare cases with subtile color gradients in 16 bit) - then I render in ProRes or DNxHR (High Quality, 422, Full Range) from LRT and feed those clips to Davinci Resolve. In Resolve I need to manually make sure that the footage will be interpreted as "full range". If you want to be on the safe side, use legal range.
Since I know how to edit Rec.2020 Material in Resolce (explained in the FAQ) I mostly render in Rec.2020 from LRT and only later export from Resolve in Rec.709.
If you want less stress, just do Rec709 rendering in LRT.

With video rendering It's not the best idea to always crank all settings up to the max. The differences mostly won't be noticeable at all and you might experience troubles if you don't know exactly what the settings do and some software along the chain is not able to deal with certain settings.

Ah, I didn't mean to imply that I threw away my raws! But I do archive them (pull drives and put them on a shelf), as I have so many terabytes and terabytes of them (not quite a petabyte yet, but I'm confident I'll have that much, one day :-)

So I prefer to have a master file to work from (my masters are on a series of three 12TB drives that I keep in a 5-bay enclosure that I turn on as necessary). It's faster and more convenient to work from a master than it is to re-render from raws (you of course know all the nuances of what to render when, I'm just writing this just in case somebody else reads this thread :-) And some stock agencies take my master files directly, instead of requiring me to re-render down to some lesser quality version, which is very convenient.

Yes, a 16-bit TIFF won't have the flexibility of a raw file, but once I edit it and, essentially, tonemap it to a final TIFF, then I can use that going forward in any other edits (assuming I don't want to re-edit it to take advantage of any new techniques that will get more out of it). Given the time savings, I'm hoping to do the same with master files for timelapses, but there are far more variables to consider when creating them that I haven't mastered yet.

I appreciate you listing your workflow, it's very helpful (and one I want to start using myself, instead of what I do now: raws in AE and render from there or Adobe Media Encoder). Mainly because of multi-threading when rendering, but also (I hope!) colour consistency, which is the whole reason I started this thread.

If you know of one, can you point me to a link that compares "full range" to "legal range", I've had very little luck finding a link myself (I really have looked, but I must be using inexact search terms, the articles I've found have been too broad/generalised).

And yes, it's not always the best idea to crank all settings to max, I agree, but I'm having trouble determining exactly why, in my case (the desire to have max quality master files). Before finally wanting to move to a (mostly) LRT edit/render workflow, I always rendered from Adobe Media Encoder as rec.709 (this because I'd usually apply some AfterEffects extensions), but I was hoping that moving to rec2020 (which I can't get from AME, only from AE or LRT) I would get higher quality master files (more info in the final file, just like aRGB vs sRGB in stills).

Ah well, maybe I'll drop back down to a full rec709 workflow, as I don't think I'm going to be able to master the reasons for a rec2020 workflow (honestly, I've read a _ton_ of blog posts and articles, but I still don't have a clear idea of exactly what, how and why, coupled with the oddities of OSX and the various apps that do/do not understand how to display different colour spaces :-) My inability to get consistent tones from LR to LRT must be a problem at my end, somewhere, but I can't use the movies that LRT is rendering for me, so it's back to the Adobe workflow.

I do very much appreciate the time you've taken to help me in this thread, I know it's a lot of work for you to help all of your users!

Yes, keep the raws in an archive and also the "master" files is a good idea. What I do is keep the TIFF intermediaries, not the rendered videos. This allows me to use LRT PRO to quickly batch produce a set of videos whenever some production company asks for something - mostly they will have their own ideas which format they want and I can deliver then exaclty to their demands. If I would keep ProRes 30 files and they ask for DNxHR 25 I'd be otherwise screwed.

Legal vs. full range: traditionally video is always "legal" range and photos are always "full" range. That's why for timelapse we have that transition which you wouldn't have in video only workflows (everything legal range anyway).
So if you feed full range video (which is uncommon) to a video editing program it might understand that automatically and to a conversion (to legal) or not - then you get bad contrast. If the video editor understands that depends on the format and it's abilities. With legal range you are always on the safe side because it's the expected range for video.

One example: if I feed Prores Full Range to Davinci Resolve, it doesn't automatically detect that. It will initially assume it's legal range and therefore expand the levels which renders a wrong contrast then. I need to manually tell Resolve that that is full range material, then it will display it properly. With DNxHD material however, Resolve will autodetect full range material.
I've explained it in this faq: https://forum.lrtimelapse.com/Thread-dav...s-with-lrt

Yes, it's complicated... :-)

Here is a good explanation about "Levels": https://www.thepostprocess.com/2019/09/2...-vs-video/

Ah, keeping the TIFFs (and perhaps never creating a master file), I never thought of that! A very good compromise between drive space usage and rendering versatility, thanks for the tip. This also solves the frame rate issue, which is a big one for me (clients asking for different speeds), I'm embarrassed I didn't think of this myself (been re-rendering from raws, or re-timing a master file in Premiere/AE, when clients have asked for different rates).

Thanks for the summary of "legal" vs "full range", that's very helpful. I rarely edit my clips together into videos (usually they just go straight to stock or a client), so I've not needed to work this out before.

That "levels" article you pointed me to answers a _ton_ of questions! It gives me a solid base of knowledge to work from, huge thanks (I wish I'd found that one myself). The confusion with levels, colour spaces and how different codecs and editing suites handle them, phew, it's more art than science! I think this solidifies my desire to stop at timelapse, when it comes to video production :-)

I don't use Resolve, but I've been meaning to learn, time to do that (I'm disappointed, and quite surprised, to learn that Premiere and AE are behind when it comes to colour management).

Ok, time to read and re-read, and come up with an appropriate, and sustainable, end-to-end workflow at last (but I'm understanding more and more why you work the way you do, and why you set up the rendering capabilities of LRT the way you have).

Great support (and it's not even directly related to LRT), I'm in your debt. Hopefully others will read this thread and find it as helpful as I have.

Thanks so much for your feedback!