Photoshop Blend Modes – Part 6
Posted by Michael Hoffman in Tutorial on February 8th, 2010
The Overlay blend mode in Photoshop is typically used to enhance contrast, making the shadows darker and the highlights brighter. Last week, we looked at a method for using the High Pass Filter in Photoshop to sharpen an image, using the layer blend mode of Overlay. Today, we’ll look at a way to use virtually the same technique, but this time to smooth an image by actually reducing the contrast in specific areas of the image.
We’ll start with this portrait from stock.xchg. The lighting has conspired against us, and as a result, the lines under the subject’s eyes, especially her right eye, and a little too noticeable and distracting.
Click to Enlarge
Our objective with this tip will be to minimize the distraction, but without resorting to the more drastic measures of cloning or blurring, which can produce an overly artificial look. Instead, we’ll bring Overlay mode to the rescue, and de-emphasize the lines by reducing the contrast – by making the shadows less dark, and the highlights less bright. In short, the opposite effect we used for our High Pass Sharpening technique.
Here’s what we’ll do: start by duplicating the background layer (press Ctrl-J/Cmd-J, or simply drag the layer thumbnail in the layers panel to the “create new layer” icon). Rename this new layer “High Pass Soften.”
Next let’s run the High Pass filter on this image. Select Filter > Other > High Pass… to bring up the filter dialog. There is only one setting, “Radius.” For this technique, we’ll want to use a little higher setting than usual, and back off later by reducing the opacity. For web resolution images, you’ll want a value between 5 and 15, for typical camera images a value from 10 to 30. I chose 20 in this case:
Press OK to commit the change. Before we set this layer’s blend mode to Overlay, I recommend desaturating the image. This will remove any color artifacts from this High Pass Layer, and prevent any color shifts to the skin tone when we use Overlay mode, and will also make it easier to see what is happening in the next steps.
Choose Image > Adjustments > Desaturate.
Now, we don’t want sharpening, we want smoothing. Instead of enhancing contrast, we want to reduce contrast. We want the complete opposite effect. We can achieve this now, by inverting the High Pass layer. When we invert a black and white image, black becomes white, white becomes black, shadows and highlights are reversed, and – 50% gray remains unchanged!
Choose Image > Adjustments > Invert.
Note the difference in the image. The edges that were enhanced by the High Pass filter now have a negative look, but the overall 50% gray of the image is intact.
Let’s go ahead and set this layer’s blend mode to Overlay. You should see an immediate softness in the image. Hold the Alt (Option) key down while pressing the “Add a layer Mask” icon in the layers panel, to create a new black layer mask that hides the entire layer:
Now, with a soft round brush set to white, with a low opacity (20%), paint on the layer mask to reveal the areas we want to soften, such as the lines under the eyes. Remember that multiple passes of the brush add density, and build up the opacity gradually from 20% to 100% as you continue adding brush strokes:
After painting in the softness in the wrinkles, you can adjust the opacity of the layer if desired to fine tune the adjustment. Here is the before and after, with the layer opacity set to 70%:
The difference is subtle! Keep in mind, we are not removing, cloning or blurring away the lines, we are simply reducing their contrast in order to shift the viewer’s attention to more important parts of the image. Once this correction is made, use last week’s High Pass Sharpening technique to add some emphasis on the eyes, and your mission is accomplished!
Click to Enlage
Stay tuned as we continue our exploration of Photoshop’s layer blend modes next week.
Possibly Related Posts:
- Upscaling Grayscale
- Photoshop Blend Modes Part 5
- Custom Black & White in Lightroom
- No Flipping Photoshop
- Photoshop Blend Mode Basics – Part 4
An Invitation To You
Posted by Greyson TipSquirrel in Uncategorized on February 4th, 2010
Upscaling Grayscale
Posted by Janine Smith in Tutorial on February 3rd, 2010
Although it’s eminently preferable to scan all your old photos in color, sometimes we don’t have the luxury of that choice. Sometimes we only have access to grayscale scans of photos, for whatever reason – even portions of the wonderful old photographic collections in the Library of Congress were, unfortunately, scanned in grayscale. Even though the color channels are, at their core, channels of ‘color’, even black & white photos have differences in the separate channels in the form of tones.
I’m often asked to estimate a digital photo restoration by analyzing scanned photos – when the client can’t bring the photo to me, they can always send the photo via email (ain’t technology grand?). When telling the client what I need from them, I always ask them to scan the photo in color, yes, even the black and white ones! The reason for this is simple: Scanning a photo in color allows you to take advantage of one of the bright stars in the Photoshop universe, color channels.
What are color channels, and why are they so important to digital photo restoration? Unless you’re going to be doing some pretty intense professional printing, the channels you’ll most likely be working in is RGB, or the Red, Green and Blue color space. Think of the channels as a sort of sandwich; the red and blue channels are the bread and the green channel is sandwiched in the middle (Fig. 1A, below) When you look at the channels palette itself, you’ll see not three channels, but four. The fourth, or, technically, the first, is the combination of the three colors, the actual RGB channel.
You can opt to show the channels in color (Edit > Preferences > Interface > Show Channels in Color), but the greatest benefit in channels to digital photo restoration is in keeping the channels in their default state, which is black and white. Each channel has it’s own depth of color and the damage in the photo is often greater in one channel, less in another. In that regard it’s a great evaluation tool. If needed, you can take out the most damaged channel, but that’s a tutorial for another time. If your photo is in greyscale, you can also ‘rebuild’ your channels in order to add depth to your photo (Fig. 2A, above).
This photo, though fine in grayscale, could most certainly be better. Pure grayscale images are generally rather flat and, sometimes, somewhat harsh. I’ve found, over the years, it’s almost universally preferable to do some tonal tuneups on black and white restorations.
An image scanned in grayscale will only have one channel because the color information will have been stripped.
The first thing you should do when bringing a flat, grayscale image into Photo shop is change the color mode to RGB by going to the Image menu and then selecting Mode. You’ll see in the popout menu that Grayscale is checked. Go down a ways and select RGB Color. Now you’ll have three colors channels, but they’ll still all be the same. In order to give you added depth, you can actually make your own color channels! Start by selecting the Red Channel in the Channel Palette.
Go back to the Image menu and select Apply Image towards the bottom. You can also select your channels directly from the Apply Image screen, right in the area marked, oddly enough, Channel! Start by leaving the Blending mode at Multiply. You can always experiment with other blending modes later, in fact, I encourage it, but this is a good place to start. Set the Opacity level to 25% and hit OK.
Select the Green Channel, either from the Channel Palette or Apply Image. In the Apply Image menu, change the Opacity level to 50% and hit OK.
Repeat with the Blue Channel, using 75% as your Opacity. Select OK.
You now have rebuilt color channels in your previously flattened photo. This gives you a great place to either start your restoration, or, in some cases, a really nice sepia tone!
Being as how this is an article on making better Black & White images, however, I’ll point out the big benefit in this exercise, in this instance, is you’ve brought back the ability to now use the Black & White Adjustment Filters on your image!
To achieve a nice Duotone look, pick a strong Black & White Adjustment filter, such as Maximum Black, and take the opacity down to around 75% so just a hint of the Sepia Tone comes through.
In the next couple of weeks, we’ll explore a couple other ways to make better Black & White restorations!
Janine Smith is an award winning restorationist. For more of her work and tips, visit her website or why not chat to her on Twitter?
Possibly Related Posts:
- Photoshop Blend Modes – Part 6
- Photoshop Blend Modes Part 5
- Custom Black & White in Lightroom
- No Flipping Photoshop
- Photoshop Blend Mode Basics – Part 4
