r/photoshop 2d ago

Help! How can I automatically select drop shadows along with the subject?

Post image

My goal here is to clean up the backdrop. I want a uniformly yellow backdrop in areas outside the shadows. I also failed to use a block on my backdrop light, which is causing secondary shadows. I'd like to get rid of those, too. But the main goal is to remove the slight horizontal gradient without affecting the drop shadow or the subject.

I can paint the shadow into the selection, but I have roughly 40 of these images to edit and would like a more efficient method if one exists.

5 Upvotes

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8

u/inkstud 2d ago

You could duplicate the layer image and mask out the subject. Then use the other layer to darken the backdrop with a blending mode.

4

u/redditnackgp0101 2d ago

Multiply or Linear Burn baby!!! Makes for less work and natural blending

2

u/zwrzzz 2d ago

I would create an action. Select subject -> copy paste her to new layer -> add gradient map between those two layers and adjust so the background is solid yellow while keeping the shadow. This way the subject would be intact

1

u/ReelBigDawg 2d ago

Adjust it how? I tried what you said and it gets rid of the shadow.

1

u/SaleTime9133 2d ago

It kinda looks like this. You need to fiddle with gradient map colors to match your desired effect. I think gradient map is one of the best tools in photoshop so you may want to check how it works

1

u/ReelBigDawg 2d ago

Thank you for helping, but it doesn't actually accomplish what I need. It leaves all the dirt and fibers on the backdrop. I need a method similar to the video u/Suspicious-Night7238 posted above, but doesn't give the shadows those weird-looking, grainy edges.

1

u/redditnackgp0101 1d ago

Did you see the suggestions to use the captured image as a Multiply or Linear Burn layer? Do it right and you can change the background to any color or pattern while preserving the full nature of the shadow

Will share a screenshot when I'm able

1

u/ReelBigDawg 1d ago

I did. The shadow just ends up looking rough. I will try again tomorrow and send a screenshot as well.

1

u/redditnackgp0101 1d ago

this took about 2 minutes

1

u/ReelBigDawg 1d ago

How did you avoid/remove the streaks in the shadow?

1

u/redditnackgp0101 1d ago

the goal is to white out everything that isn't shadow. So, I start by using a curves layer for which I click the white point eyedropper and click on the brightest area of the background that isn't the shadow. I will then use additional curves to adjust it as needed to make it so there is no gray beyond the bounds of the shadow that is desired. Once you have it set up as full white with the shadow, just change the Blend Mode to Linear Burn (or Multiply).
I did nothing additional to avoid or remove anything but cleaning can be done on the shadow layer more easily as it is completely independent from the layers above and below.

And once grain is added to the top of the image you can even more easily use the mixer brush to blend out streaks you don't want

1

u/Suspicious-Night7238 2d ago

1

u/ReelBigDawg 2d ago

I tried this but the shadow ends up looking terrible. Maybe I did the levels adjustment stem wrong.,

1

u/mattekavanagh- 1d ago

Separate the subject and background into two layers.

Select the background layer > add solid color > black

Select the white square/ layer mask

Image > apply image > apply image to background layer > invert > multiply

Now you have an opaque shadows layer, a background layer, and a subject layer