How to Remove Backscatter: The Fastest Way to Improve Your Underwater Photos

How to Remove Backscatter in Photoshop

7 Steps to Removing a Lot of Backscatter in Photoshop

It's nice to do all my editing in Lightroom, but in all honesty, I don't love Lightroom's Spot Removal tool. It feels clunky to me, and it's tough to use for precise editing or situations where it's difficult to find a source area to clone. If I have a lot of backscatter to remove, I bust out the big guns and load the image into Photoshop.

If you have a lot of backscatter to remove from an underwater photo, Photoshop is your best bet. (Tweet this)

Here's another shot from inside the Yukon wreck. This one is from inside the magazine room. There's just no way you're going to squeeze through the entrance without dislodging some (okay, quite a bit of) silt.

Backscatter Tutorial: Diver in HMCS Yukon magazine room, straight out of camera

Diver in HMCS Yukon magazine room, straight out of camera and ready for some post-processing.

Step 1: Once again, first things first, I adjust the white balance sliders to get the colors how I want them. We find then that a lot more backscatter has become visible as a result of the white balance shift:

Diver in HMCS Yukon magazine room, after white balance

Diver in HMCS Yukon magazine room, after white balance

Step 2: This could certainly be fixed in Lightroom, but I prefer Photoshop's interface for this kind of work. So I right-click the image and navigate the menus to open it in Adobe Photoshop CC.

Backscatter Removal Tutorial: Opening the image in Photoshop for backscatter removal

Opening the image in Photoshop for backscatter removal

Warning: stuff's about to get really tedious in a minute.

Step 3: So now we're in Photoshop and it's about to get real. I'll hit J on my keyboard to toggle to the Spot Healing Brush Tool. Make sure that the mode is set to "Darken" and the type to "Content-Aware." You can create a duplicate background layer to work on, if you want (I don't always do this, but it is a good practice), with the keystroke Command-J.

Now adjust your brush size again using the bracket keys and get clicking on those backscatter specks! I'll go make us some sandwiches. Holler when you're finished.

Backscatter removal tutorial: Opening up the Spot Healing Brush Tool to remove backscatter in Photoshop.

Opening up the Spot Healing Brush Tool to remove backscatter in Photoshop.

Okay, you're all done? Let's have a look.

Backscatter removal tutorial: Opening up the Spot Healing Brush Tool to remove backscatter in Photoshop.

Backscatter removal tutorial: Using the Spot Healing Brush Tool to remove backscatter in Photoshop.

Step 4: Here, we've removed most of the glaringly bright backscatter, but we're left with a lighter, hazy area that is still pretty ugly and distracting. This is where we break out the Burn Tool (O) to selectively darken it up. We'll duplicate the layer again (Command-J) and set our Range to "Highlights" so that we only darken the brightest parts of the image.

Now we draw over the hazy area with a light hand. It's easiest to work with the Burn Tool in light layers. If it's already too dark, we can lighten it up either by reducing the opacity of the layer, or by starting over with a lower value for Exposure.

It's looking better, but it's still not there yet:

Backscatter removal tutorial: Using the Burn Tool to remove backscatter in Photoshop.

Using the Burn Tool to remove backscatter in Photoshop.

Step 5: So now we have two options: we can either continue using the Burn Tool until the hazy area in the photo blends, or we can  use Curves to tweak the contrast and blend that area in one fell swoop. I'm going to go with Door Number Two here. Duplicate the layer again, and then open up the Curves Menu (Image>Adjustments>Curves or Command-M) and drag the curve until the shadows darken. I like to start around the top of the bottom-left square.

Using Curves to adjust contrast and blend shadows.

Using Curves to adjust contrast and blend shadows.

Step 6: It's way too dark at this point. That's okay! Now, dial back the opacity of the layer until the shadows look better near that hazy spot on the right side. I brought it back to about 80%. It's still too dark everywhere else, though.

Adjusting the opacity of the Curves Layer.

Adjusting the opacity of the Curves Layer.

Step 7: Finally, we'll make the Curves layer into an adjustment mask, so we can apply that Curves adjustment only to the right hand side of the image. With the Curves layer selected, hold down the Option key while clicking the "Add Layer Mask" button at the bottom of the Layers menu. Suddenly your Curves adjustment will disappear. Now we get to paint it back on in just the places we want it!

Next, we'll click the black rectangle next to our layer to select the layer mask, then select white as our foreground color. Hit the B key to toggle the paintbrush, select an appropriately sized and shaped brush, and start painting on the areas that need to be darker. If it's hard to see what you're doing, you can turn the layer opacity back up to 100% and dial it back later.

Using a layer mask to adjust a Curves Layer.

Using a layer mask to adjust a Curves Layer.

That's it! At this point, I'll do some sharpening, add my watermark, and the image is ready to go:

Inside the Magazine Room, HMCS Yukon

Inside the Magazine Room, HMCS Yukon

Before & After Backscatter Removal


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