diff --git a/Cargo.lock b/Cargo.lock
index 2b12b67..01b25f5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -28,9 +28,9 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bytemuck"
-version = "1.9.1"
+version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cdead85bdec19c194affaeeb670c0e41fe23de31459efd1c174d049269cf02cc"
+checksum = "c53dfa917ec274df8ed3c572698f381a24eef2efba9492d797301b72b6db408a"
 
 [[package]]
 name = "byteorder"
@@ -115,9 +115,9 @@ dependencies = [
 
 [[package]]
 name = "either"
-version = "1.6.1"
+version = "1.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
+checksum = "3f107b87b6afc2a64fd13cac55fe06d6c8859f12d4b14cbcdd2c67d0976781be"
 
 [[package]]
 name = "getrandom"
@@ -238,9 +238,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.12.0"
+version = "1.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7709cef83f0c1f58f666e746a08b21e0085f7440fa6a29cc194d68aac97a4225"
+checksum = "ac8b1a9b2518dc799a2271eff1688707eb315f0d4697aa6b0871369ca4c4da55"
 
 [[package]]
 name = "png"
diff --git a/README.md b/README.md
index 2f4d805..fa93836 100644
--- a/README.md
+++ b/README.md
@@ -4,4 +4,4 @@
 ### Performance analysis with Flamegraph
 https://github.com/flamegraph-rs/flamegraph
 
-If installed (`cargo install flamegraph`), run `cargo-flamegraph flamegraph` and `firefox flamegraph.svg` afterwards.
\ No newline at end of file
+If installed (`cargo install flamegraph`, `perf` linux package), run `cargo-flamegraph flamegraph` and `firefox flamegraph.svg` afterwards.
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
index 51c43cb..4b7ad15 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -146,9 +146,9 @@ fn main() {
 
     // Image
     let aspect_ratio = 16.0 / 9.0;
-    let image_width = 1920;
+    let image_width = 400;
     let image_height = (image_width as f64 / aspect_ratio) as u32;
-    let samples_per_pixel = 200_u32;
+    let samples_per_pixel = 100_u32;
     let max_depth = 50;
 
     let vfov = 25.0;