Help with Spherical Pattern on Highlight on Lightroom

Hello guys, I don't know if this the right subforum to ask this, but i already did search for my problem with many different keywords and it didn't even mention anything related to this problem i am having. So, i hope somebody here will be able to help me with this.

So recently, i've just noticed this weird spherical pattern appearing on my highlight area when editing my photos on lightroom. I'am using Fujifilm XT-20 and this editing is done on JPEG files using Lightroom 2017. At first i thought it is because the highlights clipped. But previously, i've shot many photos with clipped highlights but never ecounter this problem. So here's the photos



This is the original photo. Notice the white highlighted sky


After applying some edits, i notice the faint pattern in the sky, then i try to drop the highlight, and here's what i found


There's this spherical pattern showing everywhere in the highlight area


Different photo, same result, BUT

When i think it is because the clipped highlight, i came into several other photos with completely blown to white highlight, but shows no pattern at all! This is the example


Notice how everywhere is literally clipped to white, but after doing the exact same editing with previous photo...



No spherical pattern at all, everywhere.

This really confusing. Am i missing some setting here? is this happened on the picture itself? is my camera faulty? Or did i missed some setting on lightroom??

Help me please. Thank You

You are creating your own misery, I'm afraid.

You are processing a compressed jpg file with blown highlights!
I don't see that you gave much chance to do anything with little
data left in the file.

Two possible solutions for the future:
1, shoot RAW files,
2, protect the whites at all costs.

Better still, do both. Keep it up!

ADDENDUM

Lr has nothing to do with it… it just can't cope with the task
given the little resources at its disposal… no converter could.

The image is breaking down because you're asking too much of it.

Stop using JPGs. That's a starting point.

But the fact is that this can happen with RAW files, too, if you try to push things too far. Typically changing exposure on a large areas of (essentially) solid color (like a blue sky) will show difficulty, too.

But in this case, those open areas are ideal for severe data compression in a JPG, which means you have even less data (JPG is lossy) than in the rest of the image. And attempts to effect significant change will result in problems like this.

I've only been using LR for about 6 years now, so I may not know too much, but IMNSHO here's your short answer: you're out of luck.

Shoot RAW and you will be able to use more bit depth for adjustments than jpg. Posterization occurs when pushing a file with small bit depth, such as a jpg, too much. Shoot raw and work in 16 bit at least for adjustments, then you can bring it down if you are worried about file size.

I think i dont convey my problem clearly. No, its not the posterization that i am concerned of. It is that grid pattern that suddenly shown in the sky that bug me.

And oh, yes, i usually shoot with RAW as well. But for this photoshoot, i intentionally use JPEG because i need to capture burst shooting, and XT 20 RAW buffer cant handle that much RAW files in a single burst...

Yes i know i am asking too much from the overblown highlight. But my question is, why in some other photos, even tho the white is completely clipped, those grid/pattern did not show up?

And yes, i usually shoot with RAW as well. But for this photoshoot, i intentionally use JPEG because i need to capture burst shooting (chasing running subject), and XT 20 RAW buffer cant handle that much RAW files in a single burst...

Okay so, you mean, those symmetrical grid is the result of severe data compression on the overblown highlight? But why it only shows up in some of the photos and not on all of it? ( as the third example also have completely overblown highlight but no grid pattern at all)

Oh and yes, i usually shoot with RAW as well. But for this photoshoot, i intentionally use JPEG because i need to capture burst shooting (chasing running subject), and XT 20 RAW buffer cant handle that much RAW files in a single burst...

Is it common for image converter like this to create grid/symmetrical pattern like that over a clipped area??? I thought the usual problem will be banding or just random noise pattern. Not gridlike structure like that

Lightroom Classic lets you easily merge standard exposure photos into a breathtaking panorama. In a single step, you can also merge multiple exposure-bracketed photos (with consistent exposure offsets) to create an HDR panorama. You can see a quick preview of the resulting panorama or HDR panorama created and make adjustments to it before the final merged image is generated.
What you learned: Apply local lighting effects to a photo with the Radial Gradient tool
How does the Radial Gradient tool work?
The Radial Gradient tool applies local adjustments inside or outside of an oval shape. It comes in handy for creating natural-looking lighting effects.
Apply a highlight effect to a photo

1. Select the Radial Gradient tool by clicking its icon in the column on the right or pressing the R key.
2. Drag over the area that you want to adjust. The point where you start to drag will become the center of the radial gradient.
3. Drag the sliders in the Radial Gradient panel to make your adjustments. For example, to add an effect that looks like a lightbulb, try dragging the Exposure and Temperature sliders to the right.

Tip: Use the Invert checkbox in the Radial Gradient settings to control whether adjustments affect the area inside or outside of a radial gradient. When Invert is checked, the adjustments will be outside the radial gradient; when Invert is unchecked, the adjustments will be inside the radial gradient.
Create additional radial gradients

• To create another radial gradient in the photo, drag over the photo again and set the adjustment sliders for this radial gradient.

Tip: You can also duplicate a radial gradient to apply the same adjustments elsewhere in a photo. Right-click or Control-click (MacOS) a radial gradient pin and choose Duplicate. Then drag the duplicate pin to a new location.
Move or modify a radial gradient

• To move a radial gradient, select its pin and drag. If you don’t see the pin, press the O key several times until you do.

Tip: Pressing the O key cycles through different views of the pin and red mask that represent each radial gradient. You can choose to view the pin, the mask, both, or neither.

• To change the shape of a radial gradient, drag any of the small circles on the gradient outline in or out.
• To rotate a radial gradient, drag just outside the gradient outline.

Edit radial gradient adjustments

• To make changes to the adjustments on a radial gradient, select the pin for that radial gradient and adjust sliders in the Radial Gradient panel.

bogiva67 wrote: Is it common for image converter like this to create grid/symmetrical pattern like that over a clipped area??? I thought the usual problem will be banding or just random noise pattern. Not gridlike structure like that

It depends upon the image. I can run into the same issue with RAW images and blue skies. It may be due to gamut. You're pushing the image too far.

In any event, that breaking down is referred to as "posterization."