7. Create 3D arrows with color gradient using Adobe Illustrator

This tutorial is part of a detailed guide on making an abstract scientific illustration. You can get all the files associated with the guide here.

Result:

This was made using Adobe Illustrator CS5.1.

1. Create a new layer called FRET in the Layers panel.

2. Hide all other layers but the Background by clicking the eye-icons in the Layers panel. Select the FRET layer.

3. Make a long rectangular shape using the 'Rectangle Tool'.

4. Press down the 'Rectangular Tool' button and select 'Polygon Tool'. While you press down the mouse button to create a shape push the down-arrow button on your keyboard to change the shape of the polygon. Stop at the triangular shape. Create a triangle directly on top of the rectangle by holding down the shift key. Make sure the two objects are aligned horizontally and overlap vertically.

5. Open the pathfinder menu bar from the Window-menu.

6. Select both the rectangle and triangle. In the pathfinder box, press unite. This will join the two shapes into an arrow.

7. Rotate the arrow 90 degrees and open the Gradient panel to the right.

8. In the Gradient panel, set the gradient to 'Fade to black' and Type: Linear. Then double click the right 'Gradient Slider'.

Set the color to red and Opacity to 100%.

9. Move the middle 'Gradient Slider' to the center. Double-click the left 'Gradient Slider' and set its color to a light blue.

10. Orient the arrow downwards. Add a 7 pixel Gaussian Blur from the Effect -> Blur -> Gaussian Blur dialog box.

11. While the arrow is selected, go to Effect -> 3D -> Rotate.

12. In the Rotate dialog box, set the rotations to: -52 degrees, 24 degrees, -30 degrees, and the perspective to be 137 degrees. Press OK.

13. Position the arrow so that it points in between the two dyes.

14. Copy the arrow and insert it into the same layer, FRET. Go to the Appearance panel to the right, press 3D and set the new rotation to:

-62 degrees, 0 degrees, -132 degrees, and the perspective to 151 degrees. Press OK.

15. In the Gradient panel, set the right 'Gradient Slider' to be green instead of red. Position the arrow so that it points in between the two dyes. Select the 'Type Tool' from the left panel and type the R1 and R2 textboxes as shown below. The size of R1 is 21 pt, Arial, Bold Italic. The size of R2 is 14 pt, Arial, Bolt Italic. Subscript is achieved using

The subscripts are achieved by: Character -> 'Top Right Icon' -> Subscript.