0. Introduction

The fisheye perspective feature was added in CLIP STUDIO PAINT version 2.0.

This is a very convenient feature, but it can be a bit tricky to set up.

This TIP will skip the complicated details and introduce commonly used fisheye compositions and how to set up the corresponding rulers.

 

When watching the video, please enable subtitles for each language.

How to Set Up the Fisheye Ruler

To create a fisheye ruler, first set up a regular perspective ruler, then touch the ruler with the Object tool, and turn ON [Fisheye Perspective] in the Tool Property palette.

 

Fisheye Ruler's Field of View Circle

The outer edge of the fisheye ruler is a circle, which represents the base of the visual cone, showing the range of vision expanding from the eyeball.

The angle of this cone is what is called the field of view (FOV) in games. It is also referred to as the angle of view.

Setting up the fisheye ruler involves choosing where to place the canvas within this circle of vision, or which part of the fisheye view to use for your drawing.

Common Fisheye Compositions

Broadly speaking, there are three major compositions commonly used with fisheye lenses:

Compositions that use the upper half of the fisheye, compositions that use the center of the fisheye, and compositions that use the lower half of the fisheye.

 

 

You should choose the composition among these three that best suits the image you want to draw.

 

Now, while explaining how to operate the fisheye ruler, I will introduce how to set up the ruler for each composition.

Fisheye Ruler Vanishing Points

There are two ways to place the vanishing points for a fisheye ruler: either somewhere inside the circle or on the circumference.

 

When the vanishing point is inside the circle, lines drawn will spread outward, just like with a regular perspective ruler.

However, if you place a vanishing point on the circumference, another vanishing point in the same direction will appear on the opposite side,

and lines drawn will not spread outward but will converge within the circle.

I have set the vanishing point for depth direction in the center of the circle, the vanishing points for horizontal direction on the circumference, and the vanishing points for vertical direction also on the circumference.

 

This placement is the easiest to understand for a fisheye ruler, so when setting one up, start by creating this shape.

Fisheye Ruler Grids and Properties

Let's display the grid on the fisheye ruler.

You can display the grid from the Tool Property palette by touching the fisheye ruler with the Object tool.

Since the fisheye ruler makes it difficult to grasp space, it's good to display about two grids.

 

 

 

Next are the parameters for fine-tuning the fisheye ruler: [Distortion Strength] and [Field of View Circle Radius].

Increasing [Distortion Strength] causes the area near the circumference to be more strongly compressed,

while decreasing it results in a flatter screen, like one taken with a telephoto lens.

Increasing [Field of View Circle Radius] makes the fisheye ruler's circle larger.

This is generally set to be larger than the canvas.

The fisheye ruler is adjusted to fit the composition by tweaking [Vanishing Points], [Distortion Strength], [Field of View Circle Radius], and other settings.

It's difficult to achieve the desired composition in a single adjustment, so adjust patiently.

Composition with Canvas in the Center of the Fisheye Ruler

First, let's try a composition where the canvas is in the center of the fisheye view.

 

The vanishing points, eye level, and canvas position are roughly like this.

 

This is a screen where the eye level is straight, and the direction of the horizontal curve changes between low angle and high angle.

It's the easiest to set up because you just place the canvas in the middle of the basic fisheye view.

Although it's simple, to help you set up the ruler by referring to an example, open [Sub View] from the [Window] menu and load an image of this central composition. Feel free to download the image above for reference.

First, referring to the composition in the Sub View,

increase the Field of View Circle Radius until the canvas fits perfectly in the center of the circle.

With the Object tool, grab the largest arrow's cross mark and slightly move the entire fisheye ruler for fine adjustment.

The fisheye ruler has been set up. After trying a test drawing and confirming it looks good, adjust it further to achieve your preferred composition.

Composition with Canvas in the Upper Hemisphere of the Fisheye Ruler

Next is a composition where the canvas is in the upper hemisphere of the fisheye ruler.

This is a screen where the eye level is curved, and the direction of the horizontal curve is upward, whether it's a high angle or a low angle.

The vanishing point for the height direction is also inside the circle, not on the circumference, which seems more difficult than the central composition.

 

But it's not that complicated; it's just one extra step compared to the central composition.

First, just like before, set up the basic fisheye ruler and then increase the Field of View Circle Radius.

Next, after confirming that the eye level is not fixed, raise the vanishing point for the depth direction upwards, and you can curve the eye level like this.

Next, grab the downward vanishing point on the circumference and drag it inside the circle.

Now, the lines in the height direction will spread upwards.

I tried changing the position of the fisheye ruler and curving the eye level further, but compared to the reference image, the curve is still not enough.

So, I will increase the value of [Distortion Strength] for the fisheye ruler.

This time, the field of view circle became smaller due to the distortion, so I will increase the Field of View Circle Radius to restore its original size.

 

The position of the fisheye ruler has shifted, so I will move the entire ruler to adjust it.

 

The height direction has shifted, so I will adjust it again.

After repeated fine adjustments, I was successfully able to set up the fisheye ruler.

Setting up a fisheye ruler exactly as you envision your composition isn't difficult, but it requires patience.

Once it's set up, it's very convenient, so don't give up and keep trying!

When arranging this fisheye ruler, right-click on the fisheye ruler, fix the eye level, and then move the vanishing points.

This allows you to arrange it while maintaining the composition.

Composition with Canvas in the Lower Hemisphere of the Fisheye Ruler

Next is a composition where the canvas is in the lower hemisphere of the fisheye ruler.

 

This is a screen where the eye level is curved, and the direction of the horizontal curve is downward, whether it's a high angle or a low angle.

 

The vanishing point for the height direction is also inside the circle, not on the circumference, and lines spread downward.

The method for setting up the fisheye ruler is almost the same as for the upper hemisphere. Enlarge the Field of View Circle,

move the ruler so that the canvas is in the lower hemisphere of the fisheye view,

grab the vanishing point for the depth direction, and curve the eye level downwards,

grab the upward vanishing point on the circumference and place it inside the field of view circle,

 

The setup is complete. While the fisheye ruler can be challenging to adjust at first, you'll get faster at setting it up once you get used to it.

 

Bonus: Setting Up the Fisheye Ruler on a Rough Sketch

So far, I've introduced the minimum usage and three common compositions.

Finally, I'll share a tip for aligning the fisheye ruler to a rough sketch.

That is, before setting up the fisheye ruler, try setting up a perspective ruler with three-point perspective on your rough sketch to some extent. This makes it easier to estimate the eye level position, and by having a general understanding of the space beforehand, you can more quickly bring the fisheye ruler closer to the composition you want to draw. Please give it a try.