Holy Grail 24h needs a combined algorithm of sunset and sunrise.

Here you can post all things you think are missing within in the app – we really appreciate your input.
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BorisH
Posts: 14
Joined: October 2nd, 2023, 7:03 pm

December 15th, 2023, 11:06 pm

I would be great to have yet another HolyGrail modus that allows full nights, e.g. BOTH sunset and sunrise.
The current options only cover one of them, but most of what I want to do is full night timelapses, so I am unsure how the algorithm would deal with this.

I have not yet tried this with unleashed, but will do so tonight and will report back what this does in the morning.
However, even if it does work, it would be great to make that clear in the menu. The current options seem to say one can only do sunset OR sunrise, no both.


Edit, it does not work, because the holy grail timelapse only takes one photo, but never any consecutive one (the normal timelapse does). I will submit a bug report for this.

Thanks
Oliver
Posts: 1120
Joined: October 9th, 2018, 4:17 pm

December 23rd, 2023, 1:31 am

We do already have a combined one, it's called "EV-Smoothing 24h". But unfortunately it's not available on all cameras. The camera needs to provide the Unelashed with EV-Meter value, and the algorithm will use that, smooth it with a rolling average (to avoid flickering), and adjust the settings whenever the rolling average passes the -0.3 EV or the +0.3 EV mark.

Unfortunately, the LRT Algorithms have no correlation with EV values, so they have to be limited to one direction to work at all (or the adjustment would constantly be flipping from -0.3 to +0.3 EV alternating virtually on every photo. However, we do have a plan to add a smart detection, for example if no adjustment was made by the algorithm for a few hours, that we'd switch from sunset to sunrise. There are still some edge cases where this might not work as expected. One example would be clouds brightening the scene of a night sky and kicking the Unleashed into a sunrise algorithm, resulting in underexposed images until the actual sunrise starts.
Founder & CEO of Foolography, Hardware & Firmware developer.
labadie97
Posts: 8
Joined: October 28th, 2023, 7:26 pm

December 31st, 2023, 3:56 am

Hi,

To begin easy, not need all to bé automatic.
Just need thé possibility to change manually the
Algorithm direction while shooting timelapse.
For instance after sunset and before moonrise.

Now with my Sony caméras, I can not change anything, even thé adjust button becomes unavailable if thé phone sleep a bit and wake up after !

A really good Holly grail requires a bit manual control sometimes.
With qdslrdashboard we could do it, so hope will bé same with unleashed.
Oliver
Posts: 1120
Joined: October 9th, 2018, 4:17 pm

December 31st, 2023, 6:12 pm

Have you updated your app?
Could you let me know which app and firmware versions you're on?

The "Adjustment" value should definitely be available - if you'd change any other value, the Unleashed would immediately try to revert those changes ;-) But the Adjustment value is designed for the exact purpose of adjusting the Algorithms without causing problems.
Founder & CEO of Foolography, Hardware & Firmware developer.
BorisH
Posts: 14
Joined: October 2nd, 2023, 7:03 pm

February 4th, 2024, 1:35 pm

There's a second, maybe easier, option.

In general, you don't need to fix the 'direction' that the adjustments go, as long as you keep them smooth. Even within a timeframe where it gets darker, the camera should adjust if intermittedly it gets brighter. Indeed, you don;t want to do that from image to image, but if, say, 5 or 10 consecutive images would need it brighter without interruption, you could flip the algorithm. Once it continues to get darker, it will flip again after 5/10 images. Yes, that might introduce SOME amount of flickering, but we need to remove this in post anyway. And as long as the balance is ok, i.e. the number of consecutive image is well adjusted, I don't think it would be too bad.
I don't think you need to wait for several hours without adjustment.

And yes, I have a Sony camera, so this is currently not possible for me (have not tried the newest firmware).
Oliver
Posts: 1120
Joined: October 9th, 2018, 4:17 pm

February 6th, 2024, 11:28 am

Hi Boris,
our EV Smoothing Algorithm does exactly what you're describing - it allows the scene getting brighter and darker as often as you want, and doesn't need to "Flip" the Algorithm. This works, because it's based on EV values.

The problem with the LRT Algorithms is that they're based on a calculated value from the histogram, which unfortunately has no relation to EV values, and will vary immensely between different scenes.

The way it works is that this single "brightness" value is calculated from the first image, and stored as a reference. the Unleashed then calculates the same value for all subsequent images and compares it to the reference. whenever the value deviates by more than 10% from the reference. value, the Unleashed changes a camera setting by 0.3 EV. The problem is that a change of 0.3 EV is guaranteed to take it below the 10% threshold again, but in some scenes, it could be that a change of 0.3EV results in a change of just 1% of the calculated brightness value, and in other scenes, it might be as much as 30%! with either case, allowing changes in both directions is a moot point:
- in the 1% case, this means the direction would only ever flip after a change of around 6 EV, (20% = 20x 1% = 20x 0.3EV = 6EV)
- in the 30%, we'd be flip-flopping +0.3 EV then -0.3EV on every alternating image. as every adjustment by 0.3EV would take it under the -10% threshold then over the +10% threshold again. Limiting it in a single direction removes this problem. The worst that happens in the single direction is that the point of adjustment might be just a little offset from the ideal, but at least remains consistent over the entire timelapse.

We didn't invent this Algorithm - as the name suggests, it's the "LR Timelapse" Algorithm, by Gunther Wegner.
Founder & CEO of Foolography, Hardware & Firmware developer.
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