Taming the Light: The art and technique of exposure blending

I am often asked about my post processing and the one question that always comes up is, “Did it really look like that”, asked with a good deal of skepticism. And rightly so! In the age of digital capture, and Photoshop it is nearly impossible to tell the difference between what is a photograph and what is an illustration. Now don’t get me wrong. I am not casting any judgement on anyone. I have no problem with digital manipulation. I see photography as an art and Photoshop merely as a tool in the process of crafting the final image.  That being said, I prefer not to heavily manipulate my images to the point of complete and total departure from the scene that was presented before me. I guess I am just an old school fool, but call me crazy for rather wanting to capture something truly special as opposed to making something truly mediocre, amazing in Photoshop.

So with that, I am going to run down my post processing workflow. To start, I use Lightroom to handle the organization and RAW development of all of my files, and Photoshop for fine tuning color, contrast, tone as well as blending exposures, stitching pano’s and so forth. Let’s have a look at one of my favorite images from 2011 and discuss the techniques used to create the final result.

The first step in the process is selecting the right images for the blend. In most cases, when blending exposures for increased dynamic range is needed, I usually am working with two files (sometimes three, but not often).  The scene above was captured in Glacier National Park at sunset. The light and clouds that evening were amazing. I spent the better part of 9 days waiting for this light. I could have shot an image of the falls and then simply blended in a more dramatic sky from another shot, but I don’t roll like that. So I had to wait! The images above show the two selects for the blend with the one on the left exposed for the sky and the one on the right exposed for the land. Once I have selected my images, the next step in the process is to move into the Develop Module in Lightroom to set the final white balance, fine tune Highlights and shadows, add clarity, sharpen (slightly), correct for lens distortion, and do any noise reduction needed. If both files are exposed properly, I won’t have to make any radical adjustments to the images.

The image above shows the RAW development for the file exposed for the landscape. As you can see by looking at the two panels on the right, I made adjustments to the White Balance, Exposure, Shadows, Blacks, Clarity, Vibrance as well as Sharpening the image just a bit. This one is now ready to go into Photoshop, but first we need to make the appropriate adjustments to the RAW file for the sky exposure.

The above image is obviously the sky exposure. You can see the adjustments I have done in Lightroom (Version 4, by the way). I adjusted the White Balance, a little boost in Contrast, set the black & white sliders, added some color pop with a small increases in both the Vibrancy & Saturation sliders as well as a slight S-Curve adjustment for even more increased contrast in the sky. Remember, these adjustments are all selective and will change from image to image and photographer to photographer. There is no right, or wrong!

Now, I select both files in Lightroom and right-click Edit in>Open as layers in Photoshop. The two images now appear in Photoshop as a single PSD file with layers. Now we need to selectively blend the sky exposure with the land exposure creating a High Dynamic Range image. And yes, I always do this in Photoshop as opposed to stand alone HDR applications. It is simply more precise and the result is a natural rendition of the scene, which is what I am aiming for in my photography.

Now for this image, because the horizon was a clean break between land and sky, I used the Lasso tool to draw a marching ants selection to the region of the image I want to mask (the sky in this case). Once I have drawn the selection, I need to feather the selection before applying it as a mask. I choose to feather this selection by going Select>Modify>Feather and then setting the radius of the selection to 150. This way I have a soft selection that will blend in the sky with the land more smoothly. It does not have to be perfect because you can always go the Mask tab after applying the mask and refine the selection and feather it even further still.

The illustration above shows both the resulting blend (on the left), the mask that was applied to the blend (notice how it resembles an upside down ND Grad), and the layers with the mask applied to the sky exposure. So now that I have the mask applied and the image blend is to my liking, I will go ahead and flatten the file. The next step in my workflow is to clean up any dust bunnies and crop and straiten the image. For this shot, my sensor was actually pretty clean so dust bunny management was at a minimum. I did however apply a Free Transform move on the image correcting for a slight tilt as well as cropping out the extreme lower left corner in the image.

Now the image is ready for my four basic layers adjustments I apply on just about every image I shoot.  They are as follows: Levels adjustment (with the blending mode set to Luminosity) to squeeze both the black and white points of the slider to the edge of the histogram. This builds global contrast. Next, I apply a Curves adjustment (with the blending mode set to color) and use the white dropper and black dropper to make a selection in the brightest white and darkest shadow thereby eliminating any unwanted color cast in the image (this adjustment is a selective one, remember that you don’t always want to remove the color cast from the image). Next in the process, is a slight S-Curve adjustment done via curves with the blending mode set to normal. This helps increase contrast as well as slight bump in saturation. And finally in the four steps, the sniper rifle of color adjustments,  Selective Color. Selective color allows me to go into each color channel and lighten or darken each channel as well as change the color slightly for a more precise representation of the scene and my artistic vision.  The resulting image above is shown with the four basic layers adjustments. What a difference!

The last step in process, is to dodge and burn the image. To do this I go Layer>New>Layer. Now in the new Layer dialogue box set the blending mode to Overlay and check off the Fill with Overlay-neutral color (50% gray).  This now allows me to selectively lighten and darken regions of the image without adding noise, or effecting the color values of the image. To lighten, choose a soft brush and set the foreground color to white. To darken change the foreground color to black. The trick is to use the brush at a low opacity ( I start out a no more than 15% in the opacity slider). Now I simply select the areas of the image I want to either darken or lighten and paint it in. It’s that simple. Below is a comparison of the before and after.  The above image shows the Dodge & Burn Layer with the final image.

And now finally, I flatten the image and save. The final PSD is then shown back in Lightroom where I can apply and additional corrections to sharpness and noise reduction.

That’s it. I hope you enjoyed this write-up and it helps you with your image editing workflow. Remember, there is no substitute in Photoshop for great light, a great composition and an artistic eye.