I don't know your knowledge level so I'll repond in detail, so that all readers of various levels can get some information. Tonemapping is relatively new, and a lot of users still don't understand the differences between LUT based "normalization" and tonemapped normalization processes.
Both processes are a start to getting the image looking good. Whether you use a LUT or tonemapping to normalize, it's assumed you'll do further work to the image, as normalization is simply a process for getting a log image back to a linear space.
First, log encoding is a method of mathematically reducing the math for the data points to get more data into a lower "gross" number system. Think of it as using decimal points to get the same data set recorded with lower overall numbers. Of course, you will need to reverse that encoding back to "normal" image math in playback/use.
Second, it is never the intention of the camera makers that log recorded images are viewed in log encoded display. They are to be "normalized" to full range images.
Third, how the image is 'normalized' is always up for discussion. As any way you set your individual system up will work better with some files and not so good with others. As all normalization schemas, including especially all LUT based normalization, are built for one particular scene setup, including all factors such as total scene contrast, shadow levels, saturation, and dynamic range.
Vary any of those scene descriptors from the scene used to build the normalization LUT, and that LUT ... may brick your scene. Or at least, not play well with it. Such things as if the scene is exposed a bit lower than expected, LUT based normalization will crush the blacks. Or exposed (recorded) slightly brighter, the LUT will clip the highlights to white. Or if the scene is a bit wider dynamic range, it will BOTH crush & clip data.
Which is why most colorists ... if they use LUTs at all for normalization (and many do not, most emphatically ... ) ... tend to have a variety of LUTs for each log format that they have created themselves. And can therefore use the one that to their eyes and scopes best normalizes each different scene. They may easily have 4-6 different LUTs for each log format available.
As there is NO perfect normalization LUT for any log format. Only ones more useful for this clip than another. And also why at times a LUT "built" for one log format works so well with a particular scene encoded with a different LOG format.
Now, we add in the newer, more capable software routines to the mix. Tone mapping, which is now available in Premiere 23.x on, is one. Tonemapping is a complex mathematical process that is adaptable to the data at hand in the clip. Meaning it doesn't crush anything ever, doesn't clip anything ever, and as well as possible within the aesthetic designs of the tonemapping algorithm, remaps data rather than tossing it.
It is not at all "log" in look, nor should it be. It is a very capable method for normalization, and actually safer than about any LUT ever made.
But it is NOT expected to be 'the final look' of the image. It is a standardized normalization schema, that's all.
Tonemapping is a safer, more elegant mathematical normalization process than any LUT. And it is expected to be no more than that ... a superior normalization process.
And you are expected to then develop your image further, including Lumetri presets, as you would have done with LUTs before.
It's just a safer method of getting as much image data as possible moved into the Rec.709 color space as possible without data loss.
And in the Sequence settings menu, you can turn auto tonemapping on or off as you wish. There are times the user may wish or need to keep log media log. You can do so with that seting.
Note that Rec.709 and HLG/HDR do handle log differently ... intentionally.
Rec.709 needs linear data for the display. Ergo the log math needs to be normalized (expanded) to linear math.
But all HLG and other HDR formats are encoded in log, and the HLG space assumes log data encoding and expects to expand that data on display. So the image does not look log-ish within HLG sequences.
For most users, using the auto tonemapping for most log encoded media is the better, safer normalization choice. If you've had say Lumetri presets, you'll need to rebuild them for tonemapped clips. As you did for the LUT normalized clips.
If you leave auto tonemapping off in Re.709 sequences, you should still get log media and can do whatever you want with it.
I should also mention that there are a couple cameras that supposedly record in "log" on some settings, but don't actually do so. It's just the same as setting the camera scene settings to lowest contrast and sat, but not actually log math. There's a Fuji and Panny or two like that. Unfortunately.
Neil
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