Display performance drop down since update to the 15.5 version

Hi ​@M2A2,

Thank you for the detailed report. I'd like to dig deeper into what you're experiencing so we can investigate properly.
 

The loss of synchronization between filmstrip navigation and the Develop main view, as you describe, where the filmstrip races ahead. In contrast, the main preview freezes or goes black, which suggests it may be related to how the Develop module renders previews during rapid image switching.
 

A few things to try:

• Go to Preferences > Performance and ensure the Camera Raw Cache is set to at least 20 GB (or higher if you have the disk space). If this was reset during the update, a smaller cache could cause the Develop view to fall behind when navigating rapidly.

• Select all images in that folder, then go to Library > Previews > Build 1:1 Previews. This pre-renders high-quality previews so the Develop module doesn't need to render on the fly during navigation. This will help confirm whether the issue is render-bottlenecked.

• Go to Preferences > Performance and try changing the GPU setting. If it's currently on "Auto," switch to "Custom" and check all the options to see if the filmstrip/main-view desync persists.

• Create a new catalog, import a subset of photos, and try reproducing the arrow-key rapid scrolling in Develop. This helps us determine whether the issue is catalog-specific (e.g., related to catalog size, smart previews, or metadata) or universal to 15.5.

• Go to System Settings > Keyboard and note your "Key repeat rate" and "Delay until repeat" settings. Try setting it to a medium rate temporarily and see if the "several photos skipped" behavior improves.

Regarding the zoom level not being retained in Full Screen, this could be a distinct issue from the scrolling behavior.

A few questions that would help us investigate further:

• What is the approximate size of your catalog (number of images)?

• Are you using Smart Previews, and if so, are the originals stored on an external drive or the internal SSD?

• Does the arrow-key scrolling issue happen in all folders/collections, or only in specific ones (e.g., very large folders)?

• When the main Develop view "freezes" during scrolling, does it freeze on the last successfully rendered image, or does it go to a grey/black screen?

• Have you noticed any difference in behavior between RAW files vs. JPEGs during the arrow-key navigation?

• Is the issue reproducible when using a trackpad gesture or scroll to navigate the filmstrip, or only with the arrow keys?

Looking forward to your response.

Best regards,

Anshul Saini

Since updating to the latest Lightroom Classic 15.5 version on a MacBook Pro M1 Max, I have noticed several erratic display and navigation behaviors in the Develop module.

First, when viewing photos in Full Screen mode (F key), the zoom setting of the Develop module no longer seems to be retained. For example, if the Develop module is set to 200%, clicking on the image while in Full Screen view unexpectedly changes the view to 33%, instead of retaining the previously selected zoom level.

A second, and more significant, issue concerns navigation through the filmstrip using the arrow keys.

A short press on an arrow key can now cause several photos to be skipped. Holding the key down launches extremely fast scrolling through the filmstrip, sometimes advancing through several dozen photos. With a longer key press, the scrolling can even continue indefinitely and can only be stopped by clicking directly on the filmstrip.

During this scrolling, the main Develop view becomes completely frozen and does not keep pace with the filmstrip. The filmstrip continues to advance while the main screen is frozen or turns black, and only updates once the scrolling has stopped.

In other words, there appears to be a loss of synchronization between filmstrip navigation and the main Develop view, together with a significant loss of control over keyboard navigation.

These behaviors were not present before updating to Lightroom Classic 15.5 and appeared immediately after the update.

The problem occurs on a MacBook Pro with an M1 Max processor.