EVA1: SmallHD Focus - HDR? Enough DR? Problem with applying Looks.

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filmguy123

Veteran
The Atomos screens are "HDR" - is the SmallHD focus? It says 10-bit, 12-bit input but I am not sure if this matters or how, exactly, it translates to shooting and monitoring LOG footage with 14 stops of DR?

Included on the unit itself are 709 LUTS for Arri, Sony, Canon, etc. When I apply the included LUT for Panasonic vlog to 709, that is by default included on the smallHD focus, I always get what looks like a limited DR. Everything clips sooner than it should and looks more contrasty. The Waveforms, histograms, and zebras are inaccurate unless I tick "ignore look".

TBH I am a little bit confused as to why this - it doesn't seem to translate to my experience of applying a 709 LUT, even Panasonic's default, in Premiere NLE afterwards. It's like the monitor just displays this crushed, limited version of the applied look that makes it useless for monitoring.

If anyone could explain not just a solution, but the "why" behind this I'd love to deepen my understanding about what is going on in the image pipeline here and why this.

Thank you for any help!!
 
I've had a lot of experience with external recorders and LUTs, and to be quite honest I still don't understand how and why they may all work together so differently.

(In general, even simple external recording back in the day had a crushed signal with some cameras/recorders.)

Here are a few thoughts...

(1) On the Atomos, if you view your LOG scene in its HDR mode you can clearly see more dynamic range (with adjustments) than if you applied a LUT in the LUT section of the menu (could be the same transformation) and used it to monitor your LOG. If that's what you're asking, I don't think SmallHD monitors have this capability (not 100% sure though).

(2) For whatever reason (most likely how software is written and how it's playing with hardware), sometimes LUTs applied on external recorders look different than how they appear in NLEs (as you've mentioned). For 80% of my work, I choose to burn a LUT into various LOGs (depends on the camera). Sometimes if the scene is challenging with various light, I will monitor with the LUT but not burn it in, and then usually apply the LUT on the LOG footage later in post and see what else I may have to do to the image. This is when I noticed that the LUT looks slightly different if applied in post then when burned-in in the camera. With back-to-back cycling between the two, you would see a shift in contrast and sometimes even a touch in color.

I accepted this to be a part of normal technology behavior because how could it be identical if you think about it? One piece of technology is processing all of this in its own way and the NLEs are doing everything in their own way. I've even seen people say LUTs look differently across various NLE software (FCPX - Resolve - Premiere).

(3) Another thing to consider is that the SmallHD factory supplied 709 Panasonic LUT may not be EXACTLY the same one you're using in post. My general curiosity and experience has also led to my discovery (& theory) of how identical LUTs for a particular purpose that should look identical sometimes don't, and I believe it's because they have been worked on/tweaked behind the scenes.

Today, if you download an official "Company X-LOG to REC709 LUT" it may not look the same compared to one that you downloaded a year ago with the same title and for the same purpose.

Not sure if that helps at all, but some general thoughts of mine.
 
I don't know what built in LUT Small HD uses. It's possible that there could be a mismatch between use of Extended v Legal range, which would crush the signal some. If the monitor can accept LUTs to be loaded into it then you can download the correct LUT from the Panasonic website.

No monitor is HDR unless it specifically states so, and then it's not HDR unless switched to that mode and fed a proper HDR signal. Rec709 is not HDR and can never be. Rec2020 is required.
 
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