This post was last modified: 2020-06-22, 02:00 by Joe_Belanger.

I am getting really frustrated with LRT. I am having to do a bunch of time lapses through Final Cut Pro and use Flicker Free because LRT decided on its own to change luminance values of my images and also color temperatures in the middle of a sequence. All images have level luminance curves, nothing really complex. The attached example is an example. You can see the blue luminance curve, going up in exposure as the darker clouds move out of the frame. But the curse is smooth. I only chose two keyframes (beginning and end). You can see the two edited frame screen shots in LightRoom. I have a basic gradient to darken the end sky but also have that same gradient on the first slide. Nothing complex. When I save metadata to file and then reload in LRT it plots this crazy luminance curve for whatever reason. You can see the screen shot of my LR library file of the images in this choppy sequence and they are really exactly the same, with no special bump in light. Why is this happening? It makes LRT useless.

In the last two days of churning out 40 time lapses, LRT also decided to take command of my sequence and apply horrible corrections to images where a car might be driving by. In Lightroom that sequence is perfect, with no visible luminance jumps. So LRT is trying to correct lightning on its own, which defeats the entire purpose of using LR. I have redone some of these with zero corrections and they run through LRT fine. It only happens once I make any corrections in Lightroom.

I am really frustrated because of the time this takes and the unreliability of LRT. I totally believe this is a bug (or several bugs) in LRT. It should not be changing my color temperature if my color temperature is linear across all images in Lightroom, but it does. It should not be making lightning decisions for any images unless I apply deflicker, and even then it should be minimal and really fluid with no detectable jumps like you see here. I put the cursor on the image just before the spike and took a screen shot. Then I took another screen shot at the first peak of the jump. You can see for yourself the exposure jump. Then I did a screen grab of the images in LR of that sequence and you can see that all of the images are exposed almost exactly. I also posted my two key framed images in LR.

Something is really going on with LRT. This has happened with multiple time lapses with simple lighting.

Really could use some help here of if you need further data let me know.

Joe

This post was last modified: 2020-06-22, 09:57 by Gunther.

I can assure you that LRTimelapse doesn't apply any changes to luminosity that you don't activate by purpose. The only things where LRT changes luminosity is deflicker and holy grail wizard. In your case it seems to be something else. On the 3rd screenshot for example you can see that the left frame indicates externally changed metadata showing a different version of the image as it currently is in the LR catalog vs. the external one.

It's difficult to say, what exactly went wrong, but one thing that could cause such issues is, if you have activated "Automatically write XMP metadata" in the lightroom settings. This must be OFF as explained on https://lrtimelapse.com/install/
Please double check!

Then please do some more tests - always restart from scratch before you try: remove the sequence from Lightroom, in LRT do "Metadata/Initialize".

Another thing that I've noticed:
[quote]LRT also decided to take command of my sequence and apply horrible corrections to images where a car might be driving by.[quote]

This might be introduced by Lightroom, if you use the context sensitive tools in the Basic Panel. Background is, that if you have two adjacent images with vastly different contrast - which happens for example if a car passes by, Lightroom will apply the same develop settings in different ways to those images. This is ok for single frame photography but a major annoyance for timelapse. I've covered this exensively many times here, also in the faq: https://lrtimelapse.com/news/use-the-new...me-lapses/
The solution is to avoid Dehaze, Clarity, Whites, Blacks, Shadows, Highlights in high settings and use the tone curve adjustments for the basic corrections.

Those problems are get worse the higher the settings of those tools (from your edit of the clouds it loos as if you might have used dehaze extensively) and the more contrast changes the sequence has. For rather smooth sequences without elements popping in and out it's often no problem at all.

Please check all this things and come back to me.