Watching an episode of MythBusters I wanted to recreate a large explosion that appeared in the show. After experimenting I found a really simple technique but the final effect is great.
Before We Get Started
For this tutorial you are going to need 4 cloud photos and your main image.
Cloud 1
http://www.sxc.hu/photo/1278719
Cloud 2
http://www.sxc.hu/photo/1248804
Cloud 3
http://www.sxc.hu/photo/1282044
Dark Cloud
http://www.sxc.hu/photo/1247058
Main Image
http://www.sxc.hu/photo/890634
Step 1 Setting up the Document
We will start opening the jumping image; you don’t need to modify the image size. Save it as explosion.
Step 2 Extracting the Background
Double -click on the “Background” layer to make it editable.
We will use two techniques:
a ) To select the people we will use Pen Tool to create a path.
b) For selecting the grass we use the channels technique. You can review this technique here:
Remove the background of a complex image (extracting hair)
c) Create a new layer and paint it with a blue gradient for creating the sky.
Step 3 First cloud layer
a) Open the Cloud 1 image as is and double-click on the “Background” layer to make it editable. Drag and drop it to the main image, scale it to fit.
b) Select the Eraser Tool with a soft-edged brush. Remove the parts of the sky, you do not have to be very precise.
c) Next apply Hue / saturation to the sky: Image> Adjustments> Hue / Saturation
d) Select Colorize adjust hue to achieve a bright orange with the following specifications:
Step 4 Second and third cloud layers
a) We open the second file of clouds, drag and drop it in the main image.
b) We repeat the previous steps: delette background and colorize.
c) Set the blending mode to overlay 100%
d) We open the third cloud file and repeat the previous steps: resize, remove borders, colorize and apply 100% overlay
Step 5 Apply levels
a) Now adjust the levels to create greater contrast and brightness in the explosion. We select our first layer of clouds, open : Image> Adjustments> Levels
Adjust the levels as shown below:
b) Repeat the process with each of the layers to achieve the desired color and contrast.
Step 6 Explosion Particles
To create the particles we need to modify a brush.
a) Select the Brush Tool (B) and go to the Brush Engine (Window> Brushes)
b) Select a round brush and modify its shape. In the brush tip shape modify to make an oval. We flip Y.
c) Adjust the brush as shown below.
d) Select a white brush and paint on the outside of the explosion. Do not apply too many particles.
e) Then we will apply some motion to them, select: Filter> Blur> Motion Blur.
f) Apply an angle to match the angle of the explosion and only the necessary distance, not overdone in this effect.
Step 7 Dark Cloud
Finally we need a cloud of dark smoke behind the explosion.
a) Open the file of black smoke, drag and drop it to the main image and place it behind the layers of clouds.
b) We scale it to fit our image.
Ready, we have a realistic explosion with very simple effects. If you want you can apply another layer of clouds to create more depth.
Hope you like it.