Thursday, September 20, 2012

The Battle for Skin Texture in Photo Restoration

The original image

Photo restoration provides plenty of challenges, and some of them keep coming up time and time again. One such problem is the perpetual warfare between bringing an image back to life in terms of its dynamic range and “pop” on the one hand, and turning charmingly smooth skin texture into a case of serious blackheads on the other.

Here’s what’s going on... In many really old pictures, especially those from before 1920, the whites have dulled down, and so have the blacks, so you’re left with a murky picture characterized by a “camel hump” histogram – one big bump in the middle, and flat lines on either side. When you adjust levels to intensify both the blacks and the whites, you increase the contrast of the image. Great, that’s what we want! But not so great – the more contrast in the faces, the worse the acne that results.

The same photo before and after level adjustments. The photo is shown at actual pixel size (otherwise known as a 100% crop). Notice both the differences in this histogram and the skin texture.





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This is a challenge you’ll face time and again. But what do you do about it? There is no one right way – every photo is different. But there are a series of techniques you can try.

When doing restorations, always work in layers. Duplicate your background layer, then make the original layer invisible. This protects you from disaster. Better still, duplicate the original image, then work on the copy after saving the original. Or do both, as you cannot be too careful about this.

When you create a new layer, always opt to create a layer mask with it. This way, you can easily erase your corrections in one or more part of the image, leaving them alone in other parts. You can un-erase them if needed, without messing up your work on the next layer down. Also, before you do something you know may not work out, make a snapshot in the history panel, so you can revert to where you are.

So, the list of things to try in order to smooth out skin texture once you’ve adjusted the exposure is:
  1. Select the faces and try adjusting the levels a bit, making the faces slightly flatter (less contrast).
  2. Isolate the faces and use “Command J” to put them in a new layer. Switch to “pin lighting” blending mode, and play with the opacity of the layer. Alternatively, use the brush tool with an opacity setting of about 15 to erase the layer a bit at a time. Do this work at actual pixel size, then switch down to print size from time to time so you don’t over do it.
  3. Use the “auto tone” function under the Image menu. Play with the results, either using the Fade function or by erasing a bit at a time. You can even try switching the blending mode of your “autotoned” layer to Soft Light or Pin Light and see what happens.
  4. Use the Noise Control filters. Select the faces and put them on a new layer. Apply the “scratch and dust” filter at a setting of 1 or 2, then use the mask tool to remove the effect from eyes and mouths. Alternatively, use the Remove Noise filter and experiment with the settings. Ditto about erasing the effect from eyes and mouths.
  5. If you’re using CS6, which has a new Contrast algorithm, you can try using the contrast slider, moving it SLIGHTLY to the left (less contrasty) side. NOTE: DO NOT USE THIS APPROACH IN EARLIER VERSIONS, BECAUSE THE CONTRAST ADJUSTMENT IN THOSE VERSIONS CAN BE DESTRUCTIVE.
The "before" (right) and "after" (left) images


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There are half a dozen other techniques of varying complexity, but one or more of these will work most of the time; it all depends on how messed up the original was, and on how much enlargement you plan – the bigger the final print, the more skin texture matters.

Remember, what you are after is a smooth skin texture without loss of detail. It really helps to vary between actual pixel (or at least very large) views and more distant ones; if you don’t do that, you’ll get lost in the details and lose track of your overall goal.

Finally, stop often and have a cup of coffee or admire the lawn or start a load of laundry, then return to the project. You’ll be amazed how much more clearly you see your work after a short break. About 30 minutes is all I can take without going buggy, but your mileage will vary!

The final restored image (colorized)


Contributor Bio:
Eric K. Hatch focuses on travel and fine art photography, and is an expert in digital photo restoration. Panoramas are currently one of his favorite photographic forms. He has won numerous regional awards and a number of competitions. His work has appeared in several AAA magazines, Oxygen Magazine, Bicycling, Alaska Milepost (annual) and Wooden Boat, to name a few. He has served on the board of the Southwest Ohio Professional Photographers Association, an affiliate of the Professional Photographers of America.

Eric has also written over 70 articles, essays, speeches, features, and professional articles in the last 30 years. His work has won two national awards: a Gold Quill from the International Association of Business Communicators, and Communicator of the Year from the Aviation/Space Writers Association.

In his youth, Eric studied under Guido Organschi, and later under Skip Schiel. He is the author of Explorations in Photography,  Adventures and Advice for Advanced Amateur Photographers, which was recently released.


Explorations in Photography is an entertaining and informative how-to for advanced amateur photographers. The book covers artistic issues, explains some fundamental technical issues, and provides many hints from buying equipment to editing your photos. It also covers taking people pictures outdoors, handling nasty lighting situations, and includes a bonus chapter discussing photo restoration. Find it on Amazon here.


Websites:
General Portfolio- http://ekhphoto.smugmug.com
Blog- http://hatchphotoartistry.blogspot.com
Photo restoration- http://www.hatchphotofix.com