diff --git a/rtiow/src/bin/noise_explorer.rs b/rtiow/src/bin/noise_explorer.rs
index 448c0d3..85f339d 100644
--- a/rtiow/src/bin/noise_explorer.rs
+++ b/rtiow/src/bin/noise_explorer.rs
@@ -1,6 +1,5 @@
-#[macro_use]
-extern crate askama;
 extern crate actix_web;
+extern crate askama;
 #[macro_use]
 extern crate log;
 extern crate image;
@@ -10,7 +9,6 @@ extern crate serde_derive;
 extern crate serde;
 extern crate stderrlog;
 
-#[macro_use]
 extern crate structopt;
 
 extern crate rtiow;
@@ -41,10 +39,7 @@ use rtiow::texture::Texture;
 use rtiow::vec3::Vec3;
 
 #[derive(Debug, StructOpt)]
-#[structopt(
-    name = "noise_explorer",
-    about = "CLI for exploring Perlin noise"
-)]
+#[structopt(name = "noise_explorer", about = "CLI for exploring Perlin noise")]
 struct Opt {
     /// HTTP listen address
     #[structopt(long = "addr", default_value = "0.0.0.0:8889")]
@@ -400,7 +395,7 @@ fn noise(np: NoiseParams) -> Result<HttpResponse> {
     Ok(HttpResponse::Ok().content_type("image/png").body(buf))
 }
 
-#[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
+#[allow(clippy::needless_pass_by_value)]
 fn noise_scale(
     np: Path<NoiseParamsScale>,
     optional: Option<Query<OptionalParams>>,
@@ -414,7 +409,7 @@ fn noise_scale(
     })
 }
 
-#[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
+#[allow(clippy::needless_pass_by_value)]
 fn noise_turbulence(
     np: Path<NoiseParamsTurbulence>,
     optional: Option<Query<OptionalParams>>,
@@ -428,7 +423,7 @@ fn noise_turbulence(
     })
 }
 
-#[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
+#[allow(clippy::needless_pass_by_value)]
 fn noise_marble(
     np: Path<NoiseParamsMarble>,
     optional: Option<Query<OptionalParams>>,
@@ -570,7 +565,8 @@ mod tests {
             .client(
                 Method::GET,
                 "/noise/lode/32/32/marble/period/1.,2.,3./power/32./size/4/scale/255.",
-            ).finish()
+            )
+            .finish()
             .unwrap();
         let response = srv.execute(request.send()).unwrap();
         assert!(response.status().is_success(), "Response {:?}", response);
diff --git a/rtiow/src/bin/tracer.rs b/rtiow/src/bin/tracer.rs
index 213e0bf..4612aaf 100644
--- a/rtiow/src/bin/tracer.rs
+++ b/rtiow/src/bin/tracer.rs
@@ -92,7 +92,7 @@ fn main() -> Result<(), std::io::Error> {
         runtime.subsec_millis()
     );
 
-    RUNTIME_COUNTER.set(runtime.as_secs() as f64 + runtime.subsec_nanos() as f64 * 1e-9);
+    RUNTIME_COUNTER.set(runtime.as_secs() as f64 + f64::from(runtime.subsec_nanos()) * 1e-9);
 
     push_metrics(&opt.push_gateway, opt_hash(&opt), &start_time);
 
diff --git a/rtiow/src/scenes/mandelbrot.rs b/rtiow/src/scenes/mandelbrot.rs
index 9b590ac..7237222 100644
--- a/rtiow/src/scenes/mandelbrot.rs
+++ b/rtiow/src/scenes/mandelbrot.rs
@@ -52,7 +52,7 @@ pub fn new(opt: &Opt) -> Scene {
         Box::new(Sphere::new(
             Vec3::new(0., 2., 0.),
             2.0,
-            DiffuseLight::new(Mandelbrot::new()),
+            DiffuseLight::new(Mandelbrot::default()),
         )),
         // Earth sized sphere
         Box::new(Sphere::new(
@@ -107,7 +107,7 @@ pub fn new(opt: &Opt) -> Scene {
             1.,
             3.,
             4.,
-            DiffuseLight::new(Mandelbrot::new()),
+            DiffuseLight::new(Mandelbrot::default()),
         )),
         /*
         Box::new(Sphere::new(
diff --git a/rtiow/src/texture/mandelbrot.rs b/rtiow/src/texture/mandelbrot.rs
index 85dfb82..5ba3c55 100644
--- a/rtiow/src/texture/mandelbrot.rs
+++ b/rtiow/src/texture/mandelbrot.rs
@@ -34,7 +34,7 @@ fn generate_palette(num: usize) -> Vec<Vec3> {
     let mut rng = rand::thread_rng();
     let mut random = || rng.gen_range::<f32>(0.0, 0.1);
     // use golden ratio
-    let golden_ratio_conjugate = 0.618033988749895;
+    let golden_ratio_conjugate = 0.618_034;
     let mut h = random();
     (0..num)
         .map(|_| {
@@ -45,8 +45,8 @@ fn generate_palette(num: usize) -> Vec<Vec3> {
         .collect()
 }
 
-impl Mandelbrot {
-    pub fn new() -> Mandelbrot {
+impl Default for Mandelbrot {
+    fn default() -> Self {
         Mandelbrot {
             scale: 2.0,
             palette: generate_palette(10),
@@ -68,7 +68,7 @@ impl Texture for Mandelbrot {
             let xtemp = x * x - y * y + x0;
             y = 2. * x * y + y0;
             x = xtemp;
-            iteration = iteration + 1;
+            iteration += 1;
         }
         if iteration == max_iteration {
             return Vec3::default();