Participant

P: LrC 15.4 Persistent RGB/LAB readouts in Histogram not working in Develop

Forum|Forum|27 days ago
June 30, 2026
9 replies
296 views

This is core to my workflow, an absolutely necessary feature I use every single time I’m editing photos.

In the Develop Module, under let’s say the “Basic” adjustments panel, one should be able to adjust values (such as Exposure, Contrast, Highlights, Shadows, Whites, Blacks, etc.) while hovering the mouse cursor over a section of the photo (in the Loupe View) and see RGB values changing under the histogram.

In the latest version, the RGB values are no longer displayed under the histogram while those values are being adjusted. For example, I click the number next to the ‘Highlights’ slider and move my cursor over to a white part of the image. When I press the up arrow on my keyboard to increase the value of that number, the RGB values under the histogram *should* be displayed and also increasing. Instead, they are not displayed at all.

I have downgraded to the previous version and the program’s behavior returns to expected.

This is a brand new computer, fresh win 11, AMD Ryzen 7 7700X; 32GB RAM; NVIDIA GeForce RTX 5060Ti (16GB)

*I already opened a support ticket for this which was closed after the agent never got back to me - this is the place the second support agent sent me to submit a bug report.

**And to be clear, this happens under other adjustment panels (Tone Curve, Color Grading) as well.

Pinned Reply By Sameer K

Thank you for your patience. The team has identified this as a regression and has a fix that should arrive soon.

Best,

Sameer K

S

sarandipt@mac.com

Participating Frequently

I am also experiencing this show-stopping issue, except I spotted it with white balance adjustments.

A couple of weeks ago, i updated Lightroom Classic to 15.4.1. Last night, I updated my macOS to Sequoia 15.7.7 and Camera Raw to 18.4.1.

I just now tried to do the thing where you use the up and down arrows to adjust the white balance while hovering the cursor over a neutral area to watch the RBG readings change. (Something I've done a million times before.) The visible color is changing, no doubt, but the color readings are not budging in the slightest. I don’t see dynamic readings even if I move the cursor around the image. The whole thing can be visibly very pink or blue or whatever and the readings stay as they were. I've tried turning off the GPU and emptying the Camera Raw Cache in Preferences, without any change in performance.

Actually, if I click back into the main window, or simply hit the escape key, I get reliable, dynamic readings again, but the moment I re-enter the text box and change the number with the keyboard, dynamic update is lost again, no changes while hovering the cursor or moving it around the image, not until I get out of the text box again.

This is a productivity killer for me.

@charleeloveyou Was this really an issue in 15.4, or was it 15.4.1 when you noticed it?

J

johnt41947401

Inspiring

It started with 15.4 and 15.4.1 was released a day or so later so the discussion tends to centre around 15.4.1. I was about to report it as a 15.4 issue when 15.4.1 appeared and I wondered if that would sort it but alas no and thats now 4 weeks ago!

S

sarandipt@mac.com

Participating Frequently

Thank you. Exactly what I wanted to know!

Sameer K

Community Manager

Thank you for your patience. The team has identified this as a regression and has a fix that should arrive soon.

Best,

Sameer K

J

johnt41947401

Inspiring

@Sameer K / Sameer,

A further week has passed and still no sign of the fix you mention, how much longer do we have to wait please?

John

Sameer K

Community Manager

Thanks for the tag. We've not released any updates for Lightroom Classic yet. The team is working on a fix for future updates. Please wait for the coming updates.

Thanks!
Sameer K
(Type '@' and type my name to mention me when you reply)

J

johnt41947401

Inspiring

@Sameer K

Sameer,

These issues were raised over 2 weeks ago now and following your initial acknowledgement, we’ve heard nothing further which is not good. I’m well aware Adobe rely on users posting on these forums when issues get identified and they’re generally acknowledged quite quickly along with an indicative timescale as to when a patch will be released. I will ask the question again, what’s happening about this please?

Silence is not a satisfactory answer in these circumstances where Adobe are reliant on the goodwill of their customers to highlight issues they’ve not picked up before software updates are released.

John

L

LSS Glamour

Participant

Agreed, this issue is an absolute show-stopper for me too! If there is no immediate resolution of this I will go back to Capture One.

T

thomazf30044038

Participant

Same thing happening in the Mac version. Very very annoying and time consuming.

M

MSpears

Participant

I immediately noticed the same issue. I use a TourBox Console controller to adjust the RGB channels of dark space backgrounds and white highlight areas of astrophotography images while using the mouse to point to different sample points. Shouldn’t have to jump to Photoshop to do this.

M

MSpears

Participant

It was working on the previous Lighroom Classic version. It stopped working when I installed the latest update on on July 4th, 2026. Here is what I am seeing. From the Develop module… Tone Curve. Select a RGB channel curve. Select a control point control (example the black end). Now, click on an Input or Output value box so that it shows an edit change mode. With the mouse, hover over sample area of the image. Using the arrow up or down keys to increase or decrease the value while monitoring the RGB histogram values. I repeat this for each RGB channel.

The new update causes the values on the histogram to now appear as dashes (no values) when you select the Input or Output value box for editing.

Attached files: Adobe Lightroom RGB..jpg is what it looked like before the update.

Adobe Lightroom RGB2.jpg is what i now see with the latest update.

J

johnt41947401

Inspiring

I’m very surprised so few people have commented on this issue which is very visible. Hopefully Adobe issue an update to address this in the near future.

J

johnt41947401

Inspiring

Sameer,

Thanks for your reply, I’ve attached a video demonstrating the RGB/ LAB values disappearing after opening any dialog box, hopefully it provides the information needed to resolve this very annoying issue! As mentioned previously, this is not an issue in ACR and it started with the release of LRC 15.4. You’ll see I’m not alone in having this issue either!

Before and after adjustments is very intermittent so I’ll monitor it and if I get repeatability I’ll screenshot or video it for you?

NAS activity at start up; I optimise the catalog every time I exit LRC so its not that and my previews are stored locally on an SSD along with the catalog. I’ve noticed no fall in duration of NAS activity and I installed the update some 10 days ago and use LRC every day so I’d have thought all updating was long finished for what is a small catalog with a 2.5GB LAN connection?

Thanks

John

J

johnt41947401

Inspiring

Video didn’t attach previously!

J

johnt41947401

Inspiring

I raised a question on exactly the same issue at pretty much the same time you did and I’m in complete agreement as like you I find it very annoying and its not in ACR. Its just LR.

D Fosse

Community Expert

You should post this in the Lightroom Classic forum. This is Photoshop.

FWIW I’m not having this issue - and yes, this is something I constantly rely on when working in Lightroom Classic. Except for i7 11700 CPU, my hardware is pretty similar to yours, also RTX 5060 Ti.

You’ll be asked for the full Help > System Info, so include that.

C

charlielovesyouAuthor

Participant

Ok thank you, will do

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