If you're like me, every now and then you find yourself needing to insert a subject image into a background where the lighting between the two doesn't quite match. Your subject image may be flatly lit, while your background contains crisp shadows and highlights -- and if you don't correct the problem you run the risk of getting a load of critical comments.Often times the wisest thing to do is to keep hunting for source images where the lighting does match. But sometimes you can effectively fix lighting problems and an example of how do to this can be seen in the giant elephant image named One Way Street.Here, seemingly, the lighting matches pretty well. But it didn't start out that way...
The image started off when I fell in love with this dramatically lit street scene. To me the busy street with its long, late afternoon shadows begged to have a giant "something" inserted into it.I first tried to insert a giant robot, but eventually realized I would go mad. A giant animal would be a good deal easier, so I began searching for a source image of an elephant that matched the perspective and lighting of the street.
But finding the right elephant image turned out to be a tall order. I just couldn't find a source image of an elephant that matched both the perspective and the lighting of the street scene.I did, however, find an elephant image that nicely fit the scene's perspective. One problem -- it didn't remotely match the scene's lighting.But rather than throw the image out, I decided to try to alter the elephant's lighting to make it match.
But first things first, I masked away everything but the elephant...And then I performed a little cosmetic surgery on the big guy, adding some tusks and rearranging his feet and trunk for dramatic effect.Looking good, but now to match the lighting.
To create the simulated lighting for this scene, I resorted to a fairly simple trick. Looking at the street scene, I can see that every object has both areas of intense highlight and deep shadow. To recreate this lighting with my elephant, I'm going to need to create two separate elephants, one lit for bright sunlight, and one lit for deep shadow -- and then combine the two images.To accomplish this task, I needed two identical elephant layers, so I duped another layer of the elephant. I named the bottom layer Highlight Elephant and named the top layer Shadow Elephant.
Selecting the Highlight Elephant Layer, I began to brighten up this layer to match the golden highlight values of the elephant in direct sunlight. There are a variety of adjustment techniques that I could have used to brighten and colorize the image -- Levels, Curves, Brightness, Contrast, Color Balance, Hue, Saturation -- but in this case I used the following adjustments:Brightness : +30Contrast : +30Color Balance: Red: +10Color Balance: Yellow : -50Mind you, these are approximate tweaks, but your goal is a brightened golden elephant that now represents the elephant illuminated by direct sunlight. Admittedly, it looks pretty awful, but hang in there.
Next I next turned on the Shadow Elephant Layer. Again, using a process of trial and error, I adjusted the elephant to match the shadowed area of the image. It should be noted that shadows aren't just darker, but they are quite desaturated and with less contrast. The following adjustments got me close to where I wanted to be:Brightness : -80Contrast : -50Saturation : -80Hue : +165Now for the tricky part -- blending the two layers.
To blend the layers, I first created a Layer Mask for the Shadow Elephant Layer and then began to slowly mask off the shadow areas, allowing the Highlight Elephant Layer to show through where appropriate. I used a blurred brush set at different opacities to reveal the highlights in subtle, blended manner.This is where masking is invaluable, allowing you the freedom to experiment, start over, tweak, mask and unmask to your heart's content.The key is to study the lighting of other objects in the scene, and then match this to the elephant. When done right, it can be surprising how effective this technique is in recreating the fall of light and shadow.
Ultimately, although it took a good chunk of time tweaking the image, masking and un-masking, when I was done, the elephant pretty well matched the street scene.
Next I needed to add the huge shadow cast by the elephant -- a touch which adds a good dose of realism to the scene. There are many ways to add shadows -- using the Drop Shadow feature is one, but it won't work in this case. This one I had to do freehand.Again, I looked at the shadows cast by the other objects in the scene -- their direction, color, and blur -- and let them be my guide. The cars shadows are at least twice as long as the height of the cars, so I knew the elephant's shadow was going to extend out of the picture. That's good, as it simplified my work.On a new layer set to Multiply Blend mode, I painted in the basic shadow of the elephant in deep blue, but the shadow of the trunk and the tusk were more difficult. By experimentation I eventually arrived at a painted outline that looked right.I was careful not to paint the shadow over the two cars in the shadow, as it darkened them far too much. Instead I individually darkened these cars with the Burn Tool.Lastly I tweaked the color and brightness of the shadow layer until it matched with the cars shadows. Then added a Gaussian blur to match the shadow blur of the cars.
And finally I added tiny people standing around and riding their bicycles, gawking up at this humongous creature walking the wrong way down a one way street.Mind you this is a pretty extreme example of how to match lighting between dissimilar images. But this trick can come in handy for far simpler objects when the lighting just doesn't match.
+ in reply to...
I want this picture
Your browser does not support iframes.