Mandelbrot set FAQs

Screen shows black, or lots of black is shown in the plot

The "iterations" count needs to be increased. This will slow down the computation of the plot, but you'll see more detail in computationally-dense regions. To increase the iterations count:

hit the M key
- this will add 100 to the iterations count and immediately start re-computing the plot
- depending on the scale and location, you may have to increase the iterations by a few thousand or more

click the wrench button to open the controls menu
expand the "iterations" section
enter a new value
hit the "Go" button

Too few colors are being used

This usually happens because you are "zoomed in" on an area containing similar colors. The easiest way to display more colors is:

click the wrench button
expand the "gradient editor" section
in the "gradient" text box, add a "-mod100" to the end of the gradient
- a smaller number shows more colors on the screen, and a larger number shows fewer
- if a "-mod#" is already there, try a larger or smaller value there
- expand the "?" section inside the gradient editor for more information on how the "-mod#" works
hit the "Go" button

Stripe Average Coloring

Try stripe average coloring!

Click the wrench button to open the controls menu
Expand the "gradient editor" section
Add a zero to the gradient's "-mod#" option, or add "-mod50000" if there isn't already a "-mod#" option present
Click the "Go" button to apply the gradient
Expand the "algorithm options" section
In the "options" dropdown list, select "automatic with stripes coloring"
Click the "Go" button to run the new algorithm

For more background, tips, and examples of stripe average coloring, see this blog post.

Tips

use box zoom for better control and faster zooming when exploring the Mandelbrot set
use multiple workers to vastly speed up Mandelbrot set computation
- use 1 fewer worker than the number of cores/threads your CPU has
- for example, if your computer has 8 cores, you can try using 7 workers
- as of March 2023, workers (specifically, nested workers) don't work in Safari (iOS and Mac) yet, but it looks like it'll work soon!
to prevent accidentally changing the Mandelbrot window, use shift+alt+L to lock the window
- or use the "window lock" checkbox in the "window options" section of the controls menu
while a Mandelbrot set window is rendering, you can experiment with different gradients without restarting the computation
use the "smooth" setting in the "smooth and slope" section of the controls menu
the "slope shading" setting can be changed without causing a full re-render
- this only works after the full render is completed
once you've found a Mandelbrot set window you'd like to save as an image, render a larger size, then shrink down, to create a higher-quality render:
1. lock the window (see above)
2. in the "window options" section of the controls menu, change "render size" to 2x
3. once the larger render completes, use the "Save Image" button
4. using a photo editing software, shrink the saved image down to 50% or 25% size
if you find a location you want to save, just make a note of the page URL!

General Tips

Saving the Image

To download the rendered image, use the "Save Image" button in the controls menu
- before downloading the image, use the T key to add a legend to the final image

Centering

Use Shift+click to center the view on an exact location

Box zoom

hold the alt key (option on Mac) and drag mouse to draw a box to zoom into
this is the best way to control the zoom for slow-rendering Mandelbrot set locations

Fast zoom

Use the E key to zoom in (increase the scale by 10x) and Q to zoom out
- for fine-grained zoom control, use the + and - keys

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