Soft on Skin Texture – soft on the causes of skin texture!

The “smoothing” of skin tones, particularly for the female portrait, is a topic that is covered patchily in the literature. If you search the indexes for skin smoothing across a shelf of Photoshop books you will get a mixed response. This ranges from absolutely nothing in WOW for Photoshop, Photoshop Artistry, Studio Techniques and Real World Photoshop, through to just a few paragraphs in Martin Evening’s Photoshop for Photographers – this last one surprised me a little , but on reflection, most of the models who end up in front of Martin’s lens walk through the door with perfect make-up, young skin and gorgeous complexions anyway! At the useful end of the scale, Katrin Eismann deals with the subject in detail in her book Photoshop Restoration and Retouching, and both Jane Conner-ziser and Julianne Kost deal with it extensively in their Software-Cinema DVD’s.

What are we doing?

Firstly, we have to understand what we are trying to do. Imperfections in the skin range from slight blemishes, such as moles, over-large freckles, tea-stains (liver spots) and pimples, through to wrinkles, bags under the eyes, crow’s feet and whole scale acne. We will not be considering structural problems here, such as sagging eyelids, bent noses and double chins – this is about skin at the macro level!

The Methods

All methods soften the skin by blurring or smearing pixels about to lose detail. This provides a large number of ways of accomplishing the same task and the differences are often very subtle. Some of them are tabled below:

Soft

Each has its own devotees and for all of them you can probably find a superbly executed example in one reference or another. This is one of the joys of Photoshop and one of the frustrations for the beginner. Best advice is to try the simpler ones first and, if you want more, go on from that point. Also consider writing actions to get the bulk of the work done, making them give you average layer opacities that you can tweak individually. You might also consider writing a number of actions entitled weak, medium and strong, with differing levels of adjustment.

Jane conner Ziser

BASIC RULES

Regardless of the technique employed, there are some universal rules that are worth considering.

Viewing magnification

All retouching should be examined at 100% zoom magnification on screen. Photoshop produces jaggies and other problems when you use the goofy magnifications such as 33.3% and 66.7%. If you need to work at high magnification for precision (say 400%) then you are best to open a second window and keep this at 100% so you don’t have to keep zooming between scales. You do this by clicking Window>Arrange>New Window. Now any changes you make in the main window are immediately visible in the second window. Bear in mind that you can close either of the two windows without saving, but you will be prompted to save your work, at the appropriate time.

Raise the Opacity!

All retouching should be carried out on a duplicate layer of the background or face. Then, when you have completed your retouch, you should reduce the layer opacity to zero and bring it slowly up to the correct level, by judgement. For example if you go round a face and systematically remove every wrinkle the model will look like a plastic doll. Dropping the opacity will allow just enough of the “lived in” look to return for realism. This strategy is the most important thing that this feature should teach you, so ignore it at your peril!

A variation on the strategy is to make a retouch procedure and then hide it with a Hide All layer mask. You then have the ability to control the strength of the effect by painting with varying opacities on the layer mask – white for full strength, black for no effect and all shades of grey in between. You also, of course, get spatial control, ie you can selectively avoid blurring eye lashes, lips, eyebrows, jewellery, etc.

Where should you be doing it?

Skin roughness may be real or perhaps an artefact of digital imaging (eg over-emphasis of grain in a scan or use of a high ISO value). If it is real, skin texture will show most prominently in the area that Jane Connerziser calls the diffused highlights. This is the zone between the specular highlights and the shaded areas. In a portrait the zone might provide a good source-area for cloning texture onto an over-bright highlight. Conversely, if the model has poor skin, this is the area where it will show up most prominently and will require the greatest amount of work.

If the poor texture is the result of digital noise (for example) it will be widespread but may be less acceptable on people's faces. Cloning from good areas will not help here and you may have to resort to channel modifications such as blurring the a and b channels in Lab mode or going after a noisy channel, such as the blue channel, from a digital camera.

The Blur Initiatives – contributed by Dave Simm

Whenever you look at portrait entries in American photographic competitions and, indeed the window displays of some of the US’s most notable portraitists, the images all have one thing in common, the level of retouching by labs and photographers is almost bordering on plastic surgery.

The subject's flesh looks as smooth as porcelain, nicer than a new born baby’s; the eyes are almost like glass, they’re so bright and artificial looking – the thing that surprises me the most is just how much the buyers rave about these makeover retouching jobs.

I have never really liked retouching very much, not because I can’t do it, – it is more because the finished image just doesn’t look like the subject at the end of the day. Having said that, let me share a funny story with you. Some years ago I had an elderly, lady client, who was starting on a second career, selling property. Of course, in America all realtors have to have their pictures on a business card. So I shot a sitting of this old dear and came up with some extremely nice images. After delivering the previews, I received a telephone call from the lady, letting me know how disappointed she was with the pictures; her main complaint was that they didn’t look like her.

I was shocked, the portraits were quite beautiful and at this stage, completely unretouched, after all they were just proofs, which I hastened to explain while asking her to call in at the studio to point out her concerns. To help you get a visual impression, I would say she had been a sun worshiper as a younger woman, which meant, in later years, her complexion closely resembled a flesh-coloured prune.

Needless to say a superb retouching job made her look something akin to Marilyn Monroe; I was certain that this would delight her. With a deadpan face the woman exclaimed that this portrait was not the least bit like her. I could see what she meant but for totally different reasons. Then she pointed to her teeth and said they’re crooked, well yes they were, ever so slightly, but enough for her to be hyperconscious of it. Ok – back to the digital file and a quick cut-twist and paste just to see the beaming smile on this ever so wrinkled physiognomy…"Now that looks just like me,” she jubilantly proclaimed.

So now, all my effort was worthy of printing out as a 1” x 1.5” to illuminate her business card…and before you ask, Yes – I lost money on it because all around Chicagoland, studio business portraits are sold as packages deals…sitting, six previews, retouching and a finished print, all for a fixed price. It had, however, become a point of honour, of course, it really didn’t do me any harm to please a realtor, after all there are over 30,000 of them in greater Chicago, I wouldn’t want any adverse customer relations knocking about a potential client base of that size.

So where is all this going? Well as I said, I am just not crazy about over retouching, but if you intend to enter American print competitions you had better have a working knowledge, or at least an arrangement with a good competition lab in this country. Above all, there will be occasions like the scenario I just described, where a client, so desperately in need of plastic surgery, needs you to come to the rescue.

There is, however, one discipline of portraiture that could actually use these techniques on a daily basis and that is the Hollywood Style Glamour Portrait. I selected this tight head-shot of a bride to illustrate this feature for two reasons, the image is large enough for you to observe the changes, and working on the PPF rule (lots of pixels per face) it is very easy to make a good looking, large format print, which is the stock in trade of the glamour studio.

Getting down to Brass Tacks.

We open an image that needs retouching and with Ctrl-J (Cmc-J Mac) make a duplicate layer (I am assuming that levels or colour corrections/management have already been applied to your image). As you see there is a huge blue vein on the right temple, small lines under the eyes and, though hardly noticeable, wispy facial hair above the jaw bone.

Select the clone tool (keystroke S) and set mode to Lighten and opacity to about 25% then with a smallish soft-edge brush, sample the flesh adjacent the dark blemishes and work your way through the lines.

Now we want a Quick Mask, keystroke q, select a suitable paintbrush and go over all the flesh, but miss areas that are critical for sharp detail, like eyes, eye lashes, eyebrows, nostrils, teeth, lips, etc. By pressing q again you will see the selection you have made, now change your selection to inverse, (Shift+Ctrl I) and duplicate the layer (Ctrl-J) so that you now have the flesh only, on its own layer, by clicking the eyes in the layers palette, you will see. With this layer active go to Filters >Blur>Gaussian Blur – for this example I am up in about the 10 range. As you can see, the girl’s complexion now has an almost porcelain, doll-like appearance. If you are satisfied, you can flatten the image and print, but as I mentioned at the beginning, American photographers will now work on the eyes. (see Jane Conner-ziser in September issue – Ed.)

So there you have it – Hollywood-style skin makeover in just a few moments with Photoshop (this example was created in Photoshop 7).

All that remains for this glamour portrait is to flatten the layers, size for printing and send to the printer. Nothing has changed for me; I am still not a big fan of this style of imagery all I can say to justify it is, go back to the first few paragraphs above.

Photoshop

Lens Blur

This is a new filter in Photoshop CS and is intended to accurately portray the effects of defocusing due to depth of field. However, it has some interesting features that make it a potential tool for skin softening. As well as not mashing up the colour the way Gaussian Blur does, you can also control and add exact amounts of noise back into the image. The downside of this filter is that it is slow and you have to visit a separate dialogue box to apply it. While you can apply the filter through a depth map, it is probably better to blur the whole image area and then paint back through a Hide All layer mask. The images [1] on the right show the result.

Median, Dust and Scratches These are alternative methods of spreading pixels about. If used on a copy layer and blended with the original using the opacity slider they will work quite well. However they seem to produce banding more easily than other methods and lack some of the sophistication of the preferred method outlined below (Tapp-Zucker).

Photoshop

The Eddie Tapp-Monte Zucker Method

The following method is attributed to Eddie and Monte, who apparently devised it back in the days of Photoshop 4. Essentially you make a copy of the image and then blur it with Gaussian Blur. You then copy the blurred layer. Then you change the blending mode of the lower layer to darken and set the opacity to 40%, then change the blending mode of the upper copy to lighten and set the opacity to 30%. This technique lends itself to the making of an action to get the bulk of the work done and all you have to ensure is that the Gaussian Blur level is correct. Blur is resolution dependent but for reference, Jane Conner-ziser added 9px of blur to a 12.4MB file which was 1800 pixels wide. This would suggest that a start value for the Gaussian Blur would be ½% of the width of the image in pixels. In real terms this equates to the values below:

Chart

Note that the blur level rises as the inverse square root of the file size, so it is smaller than you might think. In the image on the right, a value of 11 pixels was used but this was toned down using the opacity slider after the selective masking.

Once you have decided upon the blur level, you flatten the two, blurred layers together or make them into a layer set. This enables you to attach hide all layer masks, so that you can paint back the effect with a white brush, only where you need it.

Photoshop

THE VERDICT

At the end of all this, which method is the best? We go for the Tapp- Zucker method with the proviso that you build an action to carry it out. That way you get the best of quality combined with speed of use.

Photo Quote: I work from awkwardness. By that I mean I don't like to arrange things. If I stand in front of something, instead of arranging it, I arrange myself. Diane Arbus