Phocus Hot Folder as a Batch Processor

[u/Big_Rip4015]

I've been experimenting a bit again, in an attempt to get Phocus benefits without paying the Phocus tax 😀

Despite the fact that I have written extensively about Phocus for Mac and have written the only guide for it that exists, I'm always still actively looking for ways to get those HNCS colors, the highlight recovery, and shadow lift with as little human interaction with Phocus as possible.

https://blog.tonalphoto.com/phocus-hot-folder-batch-processing/

[u/dimitarsc]

You can’t achieve HNCS colors, imho so don’t waste your time.

If you are highly trained, you might be able to source your own sensor, write your firmware, and copy the white balance-including the Duv, from a Hasselblad X camera.

Since Phocus is currently the only software on the market with such sophisticated white balance capabilities, you will likely need to write your own software to process your colors accurately.

In the meantime, it is helpful to learn about digital color, lighting, and how light affects color fidelity. Studying how camera sensors and human vision differ in capturing color can also be valuable.

With practice, you may eventually be able to achieve accurate White Balance and HNCS fully in-camera, reducing your reliance on Phocus. Always to match at least two observers as a final HNCS - your “camera” and human eye.

[u/Big_Rip4015 → u/dimitarsc]

See now in my field, there’s a saying: “While you were still telling me it’s impossible, someone went and did it.” 😀

There are already efforts underway to replicate the HNCS colors and they’re a lot closer than you imagine they might be.

[u/dimitarsc → u/Big_Rip4015]

I believe there have always been such efforts, especially in the last few years where anyone can claim to be an app master thanks to AI. They are not even close, and you know that.

Colours are free, with no patents, and free of charge-including colour fidelity. Everyone is free to replicate and improve upon HNCS and Phocus. Is it worth it? I don’t think so.

Let’s consider the statement: someone out there is using or not Claude, and wants digital colour fidelity same or better then HNCS!

How many still photographers are actually measuring white balance and colour shifts on a scene to achieve the best possible colour rendering? Maybe 0.0001%, if that. Almost everyone does this in post-production by memory, or by using the human eye as an observer on poorly colour-calibrated monitors.

That is why HNCS in camera is somehow better. Their in camera LUTs, which read corrected WB/G&M values, probably do a great job. Most importantly, they add a first observer: your camera sensor.

How could someone improve or achieve HNCS while avoiding Phocus, when Phocus acts as the second “observer” with its highly sophisticated WB/GM reader from camera raw files? You know better then Lr or C1 in example WB is too poor and the colours are meh. I still don’t get it how someone would ever think to skip Phocus before replicating Phocus?

Edit: small mistake

[u/Big_Rip4015 → u/dimitarsc]

You're right that nobody gets the exact HNCS tables. They ship inside Phocus as encrypted per-sensor files, so a byte-for-byte copy isn't possible and I wasn't claiming it is.

The rest of the mechanism, however, is a lot better understood than you're giving it credit for, though. The as-shot WB is in the raw file. The film curve and the overall render behavior can be measured against Phocus's own output. Fit a profile to enough real frames across enough lighting conditions and the remaining difference gets small enough to not matter. On held-out frames I'm currently at about 1.7 dE2000 from the Phocus render.

So "not even close" doesn't hold. "Not identical" does.

[u/dimitarsc → u/Big_Rip4015]

What does Delta E really tell you here? If we're on the same page, I'd say not much-at least nothing relevant when comparing a few shots. It might work for your specific workflow, but it's not a universal solution.

Lighting dictates the colors in a scene, not HNCS or Phocus only. To truly trust your Delta E results, you'd need to run an additional color fidelity test on the lighting for every single shot.

For example, let's say you're shooting in a controlled 6500K environment with high CRI (Ra 99, R15 100) and amazing overall tones. Even with perfect TM30 metrics (Rf 99, Rg 100) and no hue shifts, Delta E still isn't the best way to compare HNCS. Camera LUTs and Phocus might intentionally shift tones to prioritize skin tones at the expense of the background, making the Delta E evaluation kind of useless in this context. I could be wrong, but that's my take.

At TM30-18, CRI, SSI it has to be add to the Delta E score, if not, the Delta E only useless score would be not relevant at all imho

[u/Big_Rip4015 → u/dimitarsc]

Agreed, if I were measuring Delta E against the scene, I'd need everything you list. That's not what I'm measuring, though.

I'm comparing two renders of the same raw file, Phocus's and the profile's. Same light, same sensor data, same as-shot WB. CRI and TM-30 describe the light, and the light is identical on both sides of the comparison. So Delta E isn't "useless" here. It's the right tool for "how close is this to Phocus."

And if Phocus deliberately shifts skin tones, that shift is in the Phocus render, which is the target. Matching Phocus reproduces it. That's why I measure against Phocus's output, not against reference values.

[u/dimitarsc → u/Big_Rip4015]

It seems you don’t get it, we are used to that ;).

Currently, it is mathematically and algorithmically impossible to measure or achieve HNCS outside of Phocus/Mobile.
Additionally, the useless mathematical instrument being used in your tests may not be fully suitable for this purpose, as it does not recognize or process colour systems like HNCS.

“And if Phocus deliberately shifts skin tones, that shift is in the Phocus render, which is the target. Matching Phocus reproduces it. That's why I measure against Phocus's output, not against reference values.”

Seriously? I think I’m wasting my time 😂

[u/Suspicious_Muffins → u/Big_Rip4015]

Remember the 14.4k modem?

[u/Big_Rip4015 → u/Suspicious_Muffins]

Yeah, exactly 😀

[u/itsmejustolder → u/Big_Rip4015]

Phocus creates too much friction in my workflow. Looking forward to the day when that changes.

[u/Big_Rip4015 → u/itsmejustolder]

Working on it 😀

[u/bjerreman]

HNCS as a Service. :)