Flawless skin is something every model wants to have and every photographer tries to provide. With the digital revolution, this is now an easy task. In this article, I’ll provide some simple methods to get those flawless skins.
A peek into the history
Photographer have been trying various techniques since the last century to get soft and smooth skins without any obvious flaws. Airbrush was the tool of choice for many decades. Airbrush is an old instrument that was developed sometime in the late 19th century. It works on a very simple principle. Air is pumped through a tube to a pen like instrument. A container with color (oil, acrylic, watercolor, ink or pigment) is connected to it. The rushing out air sucks some color along with it. The air then exits from the tip at very high velocity. This atomizes the color into very fine droplets which also exit with the air. The user controls the amount of color using a variable trigger. An extremely fine degree of atomization is what allows an artist to create really smooth blending effects using the airbrush. For decades this was the tool of choice for editing photographs printed on paper. Airbrushing was extensively used in editing photos during Stalin’s purges in USSR. Old advertisements of consumer goods were all airbrushed to perfection. Photographs used to be ‘airbrushed’ as they are ‘photoshopped’ now a days. Now the technique of fine airbrushing has almost become obsolete. The only remnant being the color pumps used in car repair shops that work on the same principle. Yes, that happens to be monster-size airbrush when you compare it to the fine-art airbrush that I am talking about.
Most image-editing programs now incorporate an ‘airbrush’ tool that gives almost similar results. If you understand the concept of how this tool works, then you’ll be better equipped to touch-up your photos. Its use has taken a back-seat due to various ‘standard’ brushes available in the programs. Some more basics first. The traditional brushes use the concept of opacity whereas the airbrush uses flow. These are two different ways of coloring. Flow allows you to build up ink over and over again. A lot like ink on a piece of soft paper. The more slowly you move over the paper, the more ink you are building. Opacity is more of a computer’s way of painting. The color applied has the set opacity regardless of the time stylus spends pressed at a point. For increasing the contrast, one has to pass the same spot again. This flow attribute therefore causes brush strokes to be time-dependent, rather than motion-dependent. Traditionally the airbrush users managed both the rate of flow of color as well as the darkness of the color. The promoted technique in real airbrushing was to start with air only, then let the color flow, make multiple passes to get the correct saturation and then finally end with air again. In the airbrush tool, the paint flows out at a constant rate. So even if the tool is not moved but the mouse is kept clicked (or stylus pressed), the paint will continue to flow out at that point. The ‘flow’ is the key concept here.
Clone Stamp Tool / Healing Tool
Apart from the airbrush tool, there are various other options too now. Cloning stamp tool along with smudge (photoshop), Healing tool and smudge (gimp) and various other similar tools have made life easy for most parts when it come to touching up. Cloning stamp tool or the cloning tool, as the name says it, clones another part of the image to the target area. Healing tool in Gimp does away with any extreme changes in values, in a small area, in comparison to the surrounding values.
Surface Blur / Selective Gaussian Blur
All these tools are perfect for small amount of retouching or removing the flaws. If the purpose is to make the whole skin look smooth, these tools can be very time consuming. For such occasions, the tool of choice is Surface Blur (Adobe Photoshop) or Selective Gaussian Blur (Gimp) or Bilateral Blur (Affinity Photo). There are plugins available for various image editing programs that do the same but I’ll try to explain how these things work and how they can be used. If you come across a plugin that does the smoothing job well then the same principles are at work in that plugin.
(Marie – a close friend and an accomplished musician. Nikon D200 with Nikkor 50mm, f/2.8. Image post-processed and retouched using Gimp.)
Here is a short tutorial on how to use airbrush for getting that flawless skin look. The techniques are based on Adobe Photoshop and Gimp but with slight name changes applicable across any image-editing program featuring layers. This is just the broad concept that I’ll write about so understand it and then implement it in the way you find it comfortable.
Complete the first few steps of post-processing as usual till the ‘use of airbrush, stamping, cloning’ step. Refer to the sequence of steps here – Post Processing RAW.
Clear away any major scars, pimples or spots. Use the Clone tool (Photoshop) or the Clone tool along with Healing tool (Gimp). Smudging these spots also works fine. If the area to be covered is large, use Airbrush tool with low flow rate. Set the color of Airbrush using the Dropper tool, from adjoining skin.
For best results use a pressure sensitive tablet and stylus for airbrushing. Airbrush effects are smoother and more gradual when done this way. With a pressure-sensitive pen/stylus, you can configure your airbrush tool to apply more or less ink depending on how hard you push down. This makes smooth, gradual shading much easier.
After doing away the obvious spots, next step is to get that flawless, soft skin. The simplest tool to achieve this is the ‘Surface Blur’, ‘Bilateral Blur’ or ‘Selective Gaussian Blur’ (depends on the software being used). This is a method of blurring surfaces with color values close to each other. This helps blur the pixels in the image (making it look smoother) without affecting the edges. There are two options available in this tool. The threshold and radius. Both have to be adjusted in such a manner to achieve the required amount of blur while still maintaining the sharpness of the features. Too much of blur will make the selection appear artificially blurred.
To use this tool, I recommend opening a duplicate layer and then using a mask. The blurred skin can then be painted down on the main image or merged with the main image layer.
Apply sharpening on the overall image. (Sharpening) If sharpening is applied before softening the skin, the skin flaws also get exaggerated. So it is best done after the above steps.