Hi,

I did some day-night-day holy grails using QDSLRdashboard running on a Samsung Galaxy A tablet connected via USB to a Nikon D850. The histogram over the whole time span is kept to be fill the lower half, so that day sky or milky way core is not overexposed.

When looking at the raw footage, the brightness is overall okay. See clip from preview footage: https://youtu.be/CrnX_HcwuBM

In the attached picture the curve of the Holy Grail Wizard is shown. If I keep the night phase steady, then dusk gets totally overexposed and dawn gets totally underexposed. If I rotate and stretch the curve to be close to the horizontal line in average, then it results in changes during night phase where it shouldn't be.

I could get around this by adjusting the exposure of the keyframes in Lightroom, but this then causes high dips, which I could get rid of by 10-20 times multipass deflicker, which takes a long time. The final result looks good and is shown here: https://youtu.be/vOE3_HYfpCA

What am I doing wrong here that the Holy Grail Wizard curve does not over/underexpose the keyframes in dusk/dawn?

Regards,
Bernd

Two things:
1) Holy Grail Wizard doesn't work great with such a large span in the luminosity curve, especially since it goes down and then up again while covering the day to night to day span. As you can see, rotate and stretch don't allow to bring the curve close enough to the center line. For such situations I recommend to leave out the Holy Grail Wizard and use the Visual deflicker only to level the Zig Zag of the adjustments.

2) Any spikes on keyframes in the luminosity curve after Auto transition and Visual Previews generation are an indicator that something went wrong with the editing because it means that the keyframes develop differently than the inbetween frames. This could be the usage of unsupported tools, mess up with the masks etc. Before continuing the workflow, this needs to be sorted out!
Please check that you have the correct masks version set according to your Lightroom Version (preferably work with the latest Lightroom Classic and therefore set Masks to 2.0). Also make sure to have the very latest Adobe DNG Converter installed! https://lrtimelapse.com/install/

The spikes on the keyframes came from adjusting the exposure in Lightroom after it was modified by Holy Grail wizard.

It's totally fine to adjust the exposure in Lightroom, but then, after you applied the auto transition in LRTimelapse, there should be no spikes. Maybe you forgot to apply the auto transition?

I'm sure I did the autotransition every of the five times I reprocessed the sequence from scratch. :-) Maybe the ca +/- 4 f-stops offset introduced by the Holy Grail Wizard are too much for the autotransition.

I wonder if it would be useful to be able to align the Holy Grail Wizard generated luminosity offsets to a free defineable Bezier curve across the whole image sequence and not just a ramp. This could allow to better control the brightness during the different phases (day, dusk, night, dawn, day). An overkill for single dusk or dawn timelapses but probably useful for whole day timelapses.

Basically doing multi-pass deflicker has a similar effect, but one can't really control the resulting brightness as the adjustment spikes introduced by Lightroom editing are smoothed out. Plus with clouds passing the night sky this could introduce false flickering when using reference frame in the sky.

This post was last modified: 2023-09-19, 17:23 by Gunther.

In your second screenshot you can clearly see that something is wrong, since you applied the Auto Transitions there shouldn't be any spikes.

I already gave you possible reasons for this which you should double check. But since I don't know more about your editing and even conditions you are working in, it's hard to tell, whats wrong.

So let's try to figure out:
- What's your Lightroom Version
- What's your LRTimelapse verison
- Which Version of Adobe DNG Converter do you have installed?

Now do a fresh workflow. Remove the folder from Lightroom and do "Metadata / Initialize" in LRTimelapse.
Do some simple editing in the basic panel only, leave the Masks/Gradients out for now.

See if the problem happens again and send me a the log (info menu / show log).

Lightroom 12.5, LRTimelapse 6.5.2, DNG converter 15.5.0.1595, MacOS 13.5.2 on a Macbook Pro M2.

Oddly I can't reproduce that spike issue after autotransition anymore. Usually in IT when debugging the issue disappears :-D

In the past I did several times "Clear all LRTimelapse Editing" and reset develop settings and read metadata in Lightroom. I had same issue with different timelapse sequences and did redo them because of contrast flickering and replaced contrast with S-shaped tone curve instead. Did not use gradients, only a crop/rotate transition because tripod was not level.

This post was last modified: 2023-09-20, 08:33 by Gunther.

Ok, please keep observing it and see if you can get a pattern. Reread my answers here in this thread, you'll have all information there about reasons why this could happen.