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Flicker / Flash with Same File Settings - Printable Version

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Flicker / Flash with Same File Settings - sdillon001 - 2019-04-29

I have several frames where the exposure settings don't change from one frame to the next but there's an increase in brightness. The visual luminance goes from 0.528 to 0.530 which causes a washed out "flash" over the whole lower portion of the image, but both files are f/13.0, 1/6th sec., 50 ISO, with an 8 second interval (attached file). The Lightroom adjustments are also exactly the same for both files 26 and 27 - see attached.

This has been a huge issue for me. I'm only editing with the sliders in the Tonal Curve region as you recommended in a response to a previous question about flicker, but what I don't understand is that I see you and LRT Youtubers like Emeric Timelapse and he and you bot edit using the normal, basic development sections in Lightroom and your videos turn out fine. I'm super delicate with my edits and only use the Tonal Curve sliders and I get frames with flicker that makes the whole sequence unusable. What am I doing wrong?

I tried multi-pass deflicker hoping it would remove it as I've seen in other tutorials, but that didn't help.

I've uploaded the video here: https://youtu.be/5FU9KB8miKk

(note, there was a blue light from a mall carnival ride going on and off behind the building to the lower right, so that was at the scene)

Please let me know if you need more info.

Lightroom file #26: https://postimg.cc/TKQcPxVq
Lightroom file #27: https://postimg.cc/FdSc0XL6


RE: Flicker / Flash with Same File Settings - Gunther - 2019-04-29

I don't see much flicker there in the youtube video. The footage might have some aperture flicker, since you shot with f/13, but LRTimelapse's Visual Deflicker should be able to remove that totally.
I'd recommend to set the reference area a bit differently, don't put it so close to the edge of the frame, since the aperture flicker might also cause changing vignettes. Put it in the sky, but more on the left side and with a bit of distance from the edges.
On the right, over the city, there seem so be some pulsating light pollution due to some illumination appearing when it's dark, you woul'd want the reference area to cover that and that's not something you can remove.
After you have a fairly good result, just export and render with some Motion Blur applied, this will ease any residual minor flicker effects.


RE: Flicker / Flash with Same File Settings - sdillon001 - 2019-04-30

Thanks again Gunther, I'll try that too. Could you please explain a bit more regarding there being aperture flicker because I used f/13? I was trying to maintain depth of field

I'm shooting with a Sony A7RII


RE: Flicker / Flash with Same File Settings - Gunther - 2019-04-30

See the section "The Reason for Aperture Flicker" here: https://lrtimelapse.com/tutorial/true-holy-grail-auto-ramping/
But don't worry, with LRT5 you don't have to worry about closing the aperture anymore, because the visual deflicker will completely remove any aperture flicker.