Reduce default frame count to a sane number.

README.md

@@ -1,6 +1,8 @@
 # Natural Log Fractal
 
-Created by iterating `z' = ln(-z) / ln(z)`.
+Created by iterating `z' = ln(-z) / ln(z)`. I haven't seen this fractal
+anywhere else, discovered it while messing around with some shader code.
+Reproduced here to learn multithreading in Rust.
 
 Usage:
 
@@ -10,7 +12,7 @@ make
 ```
 
 This will generate a series of frames zooming into the fractal (default is
-200), and link them together into a video. May take a while to run, depending
+20), and link them together into a video. May take a while to run, depending
 on your CPU.
 
 ![h.png](h.png)

src/main.rs

@@ -2,7 +2,7 @@ use image::{ImageBuffer, Rgb};
 use rayon::prelude::*;
 
 // Number of frames to generate.
-const FRAMES = 200;
+const FRAMES = 20;
 
 // Frame size.
 const IMGW: u32 = 1024;