Develop module Removing disconnected objects: Select everything, then Subtract

[John R Ellis]

Lightroom Version Number

13.4

Operating System

1. Windows 11
2. macOS 14 Sonoma

The guidance provided by Adobe and the Lightroom Queen article on Generative Remove states the need to "Select the entire object/person, including ... any disconnected parts (such as a hand on someone else’s shoulder). " If you don't select the entire object or person, Remove is amazingly clever at generating something that best matches the remaining parts, which we perceive as "replacing" rather than "removing".

But there's a gotcha in the current Lightroom Classic user interface, and selecting an object with disconnected brush strokes makes it more likely Remove will "replace" rather than "remove". To avoid the gotcha, follow this rule:

Select all of the disconnected parts with a single set of connected brush strokes, then refine with Subtract to remove the unwanted parts from the selection.

Gory Details

When you add a refining brush stroke more than a very small distance away from the first stroke, LR Classic (but not LR Desktop) treats it as a separate selection (with its own pin), and the remove algorithm runs on the two selections separately, not as a single unit. This makes it more likely that each generated replacement will be "replacing" rather than "removing".

In this example (motivated by a post in the feedback thread), I want to remove the deck railings, so I select the railings on the left and then on the right, with two different brush strokes:

After clicking Apply, Remove treats the disconnected brush strokes as two separate selections, each with its own pin:

Remove has generated a replacement for the two selections separately. When it generates the first replacement, it matches the remaining railing in the second selection, and when it generates the second replacement, it matches the first selection (or its replacement). As a result, it generates new variants of the railing. When you select one of the pins and click Variations, you see variants for just that selection (and all of the variants are railings).

Thus, you need to select the entire railing with one connected brush stroke:

That successfully "removes" the railing but generates a funky brass door handle:

So to prevent Remove from modifying the wood divider with a door handle, refine with a Subtract brush to remove the divider from the selection:

LR still treats this as a single selection, even though it's visually indistinguishable from two separate brush strokes. With this single selection, Remove successfully removes the railing without modifying the wood divider:

Here's another example, where I want to do a Stalinist airbrushing away of a disfavored family member. If you make three disconnected brush strokes to select the different parts of the person, you end up with another person generated as the replacement:

(Note that the lower-right small brush stroke is sufficiently close to the larger brush stroke that LR considers the two to be one selection, whereas the left brush stroke is considered a separate selection/pin.)

But if you select all the parts of the person you want removed with connected brush strokes and then do a refining Subtract to deselect the parts that shouldn't be removed, the results are surprisingly good:

Regarding this surprising behavior of refining brush strokes, Adobe employee Rikk Flohr says, "Lightroom Desktop and Lightroom Classic behave differently in this regard and that both behaviors are being evaluated while the feature is in Early Access. "

 

[Victoria Bampton]

Excellent examples John, I’ll update the post to link to this tomorrow

 

[bobsomrak]

Thanks @johnrellis
I do not have much need/use for Generative Remove but this is a great tip. Hopefully I will remember it if I ever need it

 

[sgandy]

The guidance provided by Adobe and the Lightroom Queen article on Generative Remove states the need to "Select the entire object/person, including ... any disconnected parts (such as a hand on someone else’s shoulder). " If you don't select the entire object or person, Remove is amazingly clever at generating something that best matches the remaining parts, which we perceive as "replacing" rather than "removing".

But there's a gotcha in the current Lightroom Classic user interface, and selecting an object with disconnected brush strokes makes it more likely Remove will "replace" rather than "remove". To avoid the gotcha, follow this rule:

Select all of the disconnected parts with a single set of connected brush strokes, then refine with Subtract to remove the unwanted parts from the selection.

Gory Details

When you add a refining brush stroke more than a very small distance away from the first stroke, LR Classic (but not LR Desktop) treats it as a separate selection (with its own pin), and the remove algorithm runs on the two selections separately, not as a single unit. This makes it more likely that each generated replacement will be "replacing" rather than "removing".

In this example (motivated by a post in the feedback thread), I want to remove the deck railings, so I select the railings on the left and then on the right, with two different brush strokes:

View attachment 23742

After clicking Apply, Remove treats the disconnected brush strokes as two separate selections, each with its own pin:

View attachment 23745

Remove has generated a replacement for the two selections separately. When it generates the first replacement, it matches the remaining railing in the second selection, and when it generates the second replacement, it matches the first selection (or its replacement). As a result, it generates new variants of the railing. When you select one of the pins and click Variations, you see variants for just that selection (and all of the variants are railings).

Thus, you need to select the entire railing with one connected brush stroke:

View attachment 23746

That successfully "removes" the railing but generates a funky brass door handle:

View attachment 23747

So to prevent Remove from modifying the wood divider with a door handle, refine with a Subtract brush to remove the divider from the selection:

View attachment 23748

LR still treats this as a single selection, even though it's visually indistinguishable from two separate brush strokes. With this single selection, Remove successfully removes the railing without modifying the wood divider:

View attachment 23749

Here's another example, where I want to do a Stalinist airbrushing away of a disfavored family member. If you make three disconnected brush strokes to select the different parts of the person, you end up with another person generated as the replacement:

View attachment 23750 View attachment 23751

(Note that the lower-right small brush stroke is sufficiently close to the larger brush stroke that LR considers the two to be one selection, whereas the left brush stroke is considered a separate selection/pin.)

But if you select all the parts of the person you want removed with connected brush strokes and then do a refining Subtract to deselect the parts that shouldn't be removed, the results are surprisingly good:

View attachment 23752 View attachment 23753

Regarding this surprising behavior of refining brush strokes, Adobe employee Rikk Flohr says, "Lightroom Desktop and Lightroom Classic behave differently in this regard and that both behaviors are being evaluated while the feature is in Early Access. "

Great info but to Adobe Engineers I would say, "You named it the Remove Tool, if you want to have it do removals and generations add a switch so we can tell it what we want."

 

[Johan Elzenga]

Great info but to Adobe Engineers I would say, "You named it the Remove Tool, if you want to have it do removals and generations add a switch so we can tell it what we want."

It's called the Remove tool because it is supposed to only remove things, not generate new things based on text like Photoshop can. When it does generate new things, then that's because you left traces of something that need to be matched to something.

 

[Paul McFarlane]

"You named it the Remove Tool, if you want to have it do removals and generations add a switch so we can tell it what we want."

Good one to put as a Feature Request (link at the top of the page).

 

[John R Ellis]

Unfortunately, Remove selections in LR Classic 14 still behave the same, confusing way. I haven't tested LR Desktop or Camera Raw to see if they've been changed to work like LR Classic.

 

[Victoria Bampton]

I haven't tested LR Desktop or Camera Raw to see if they've been changed to work like LR Classic.

Desktop, at least, was changed to match Classic's behavior. Apparently, they didn't hear your excellent argument!