Redfern Photography Blog » Blog of Calgary photographer, Lisa Redfern.

For a change of pace, I thought I’d post a Photoshop tutorial sharing some of my methodology for photo editing. Note: none of these photos are from clients of mine.

Even though someone’s teeth can look nice in person, sometimes warm light reflections and shadows can cause their teeth to look much darker or yellower than they actually are. In most cases, you’re working with a photo where someone wants to look their best, and a quick tooth touch-up can improve the entire photograph. If you’re a photographer, ultimately you want your clients to be happy with their photos; and if you’re a designer, you can’t really use a photo in a layout if the person has noticeably yellow teeth.

I have, over the course of my career, had to whiten hundreds of sets of teeth. Most of those were for advertising products for dentists — who are very demanding clients when it comes to the appearance of teeth! Digital tooth whitening doesn’t have to be a painstaking process. I’d like to share the method I came up with, which is pretty fast and gives what I think are natural-looking results. Please make sure that you have done the overall adjustments and corrections to your photo before you work on the teeth. It should be one of the last steps. If you’re going to adjust brightness, color, or levels after you’ve done specific adjustments like the teeth, you’ll likely run into some problems and make your job harder. Always start big and work down to specific touch-ups.

For our tutorial example, here is a lovely set of teeth that have a very natural off-white color:

Nothing really wrong with them, but they definitely have a yellowish tone.

The first thing you want to do is select the teeth themselves. I like to use the polygonal lasso tool, set to feather 2px with anti-aliasing turned on (on a high-res photo). Feel free to use your preferred selection method, but don’t set the feather too high or the end result will be glowy teeth. You really just want to feather the selection a little so you don’t have obvious sharp lines. Make sure not to select the gums or area behind the teeth. Also don’t select any back teeth that are partially hidden or in shadow.

Once the teeth are selected, go into your layers palette and create a ‘Color Balance’ adjustment layer. (Click the little yin-yang like icon at the bottom of the layers palette to bring up the adjustment layer options.)

Once you have selected the ‘Color Balance’ adjustment layer, a window will pop up. In general with this tutorial, what we’re trying to do is pull out some of those yellowy tones, and instead use blueish tones, which read more as white in the shadows. We don’t want to aim for perfection here, just an improvement. As a rule of thumb in this step, you’ll usually go further with the bottom-most Yellow | Blue slider, and more conservative on the top Cyan | Red slider. Make sure “Preview” is checked on. Don’t touch that middle slider, and don’t bother going into shadows and highlight adjustments — stick with midtones. The values I’ve used in the image above may not work for the photo you are adjusting. Use your judgement and go with what feels natural towards Cyan and towards Blue. Click “OK” when you’re happy with the color. This is only the first step and you can always go back to change it later by double-clicking the adjustment icon beside the mask in the layers palette.

Now, it’d be a total waste of time to select those teeth all over again for the next adjustment layer we’ll be using. Right-click the mask in the layers palette and “Add Layer Mask To Selection”.

Then make a new adjustment layer the same way we did before, clicking the icon at the bottom of the palette and selecting “Hue/Saturation” this time.

Again, you will get an adjustment window popping up. At this stage we’re turning down the saturation, and upping the lightness. Again, use values that look natural for your image (make sure ‘Preview’ is checked). Don’t touch the Hue slider. You always want to have some tone remaining in the teeth — you don’t want to make the mistake of making them bright, featureless white. Teeth that are completely blown out with a complete absence of shadow and highlight look fake and strange. There is no dodge tool used in this tutorial for that reason. Use the same values I have if you’re unsure. Click OK when you’re satisfied.

And voila, here is our final result! If you are working with some super yellow, dark teeth, you may need to add a third adjustment layer of Brightness/Contrast using the same selection from the teeth, and upping both the brightness and contrast. In most cases, you’ll only need the two adjustment layers I’ve used here, and in some cases the Color Balance will be enough. This one is a fairly subtle change:

We haven’t lost any of the actual tone of the teeth, we have simply changed the color of them to provide more of an appearance of whiteness and reduction of yellow. Here are two more examples of sets of teeth where I used the same technique, although these were more in need of change (and had more dramatic results):

The back teeth that were in shadow and looked gray instead of yellow were not adjusted, since they were already at the desired tone.

On this one I had to go back and edit my mask because the lines were originally too sharp — using a soft-edged eraser, I took away some of my layer mask for a more subtle fade to the back. Speaking of which…

Adjustment Layers?!
If this is the first time you’ve worked with adjustment layers, you might be wondering what the point of is, instead of going through the Image — Adjustments menu. One very good reason: non-destructive editing. When using adjustment layers, your selection/mask is editable, as are the adjustments themselves. You can turn them on and off, make them transparent, or trash them altogether if they aren’t working. Non-destructive editing is a wonderful time-saver, and eliminates repetition of selections or starting over when editing doesn’t quite work out. Plus, since they are masks, they don’t have to be all or nothing, on or off. You can use a transparent brush and add or remove subtle hints of the mask. Very exciting stuff!

When I am editing photos, I always save an editable PSD file, and then flatten and export a JPG or TIF to actually use or print. If I have to make further changes, I trash the flattened file and go back to my layered PSD, generating a new flat file when I am done. It seems like some extra work, but the moment you have to go back and adjust or remove changes you have made, it’s something you’ll be very glad to have saved.

When editing layer/adjustment masks, make sure to click on the mask itself, and that your background and foreground colors in Photoshop are set to the default (shortcut is to hit the letter D on your keyboard). Then just start brushing or erasing as you normally would (on the photo itself). Your eraser and your brush will use to remove or add to the mask, respectively. Make sure you click back on the layer if you want to do anything else to the photo, otherwise the layer mask is still “active”.

As a last note…
If you’ve brightened teeth, you’ll usually need to brighten the subject’s eyes as well. It looks unnatural in a photo to have bright white teeth and dark whites of the eyes. It makes your editing stand out much more. I wouldn’t use the same technique as in this tutorial for the whites of the eyes, unless they are looking quite yellow — and never use it for the iris or pupil or you’ll change their eye color, a lot. A simple levels for the whole eye will usually work, although sometimes you need to do the whites and the iris & pupil separately so you don’t get glowing, supernatural eyes. As with the teeth, I would recommend leaving some tone in the whites of the eyes for a more natural look.

Next tutorial?
I’d like to keep doing these tutorials, so what would you like to see detailed next? Fixing blemishes and skin imperfections? Doing digital makeup? Reducing shiny skin? How to remove someone from a photo? Something else entirely that you deal with often and think “There must be an easier way”? There are countless tutorials out there teaching cool glowy special effects, but I’d like to focus on the practical day-to-day editing that lots of us use Photoshop for. Please leave a comment with your suggestion and include your e-mail address, and you’ll be notified once the next tutorial is posted!

- Written by Calgary Photographer, Lisa Redfern of Redfern Photography