Phoenix Imaging

Digital Fisheye in PhotoShop

No doubt we've all seen those distorted images taken with Fisheye lenses that cost more than most people can afford, but never fear, help is at hand. Fisheye lenses come in 2 types, Circular (which, as the name suggests, give a circular image on film) and Full Frame (which produce distortion across the whole frame. So let's try and simulate those effects in Photoshop. First using this image of Coal Clough Windfarm, first let's try to simulate a circular fisheye effect.

1. First we need to create a circular selection using the eliptical selection tool. Starting in the extreme top left hand corner, hold down the SHIFT key and drag the cursor down to the extreme bottom right corner of the image (see fig. 1)

2. Now, using this selection we create a new layer via Layer -> New -> Layer via Copy (see fig. 2)

3. Next, after activating the Background layer, create a new layer (which should appear behind the layer containing the circular selection) and fill it with black (see fig. 3)

4. After activating the front layer, click on the thumbnail whilst holding down the CTRL key to create a selection from this layer then apply Filter -> Distort -> Spherize (see fig.4)

5. With the Spherize filter control panel open, we set the amount to 100% and mode to "Normal" then click OK (see fig.5)

Here is our finished image . . .

Now lets try and simulate the effect of a full frame fisheye using this image taken in Tuscon

6. First we need to increase the canvas size of the image, but by how much ? Basically the width and height of the enlarged canvas need to be the same as the diagonal of the original image. If you remember your high school trigonometry, the square of the length of the diagional equals the sum of the squares of the two sides. So for this 1600 x 1200 pixel image that gives a diagonal of 2000 pixels. So leaving the image centred, I increase both the width and height to 2000 pixels (see fig. 6.)

7. Now we apply the Spherize filter, setting the amount to 100% and the mode to "Normal" (see fig. 7.)

8. Finally we again use the Canvas Size tool to crop the image back to it's original size (1600 x 1200 pixels) (see fig. 8.)

And here's the completed image