diff --git a/src/decoder/image.rs b/src/decoder/image.rs
index f37b2b1..fe5a40a 100644
--- a/src/decoder/image.rs
+++ b/src/decoder/image.rs
@@ -518,7 +518,7 @@ impl Image {
     }
 
     pub(crate) fn colortype(&self) -> TiffResult<ColorType> {
-        let is_alpha_extra_samples = match self.extra_samples.as_slice().get(0) {
+        let is_alpha_extra_samples = match self.extra_samples.as_slice().first() {
             Some(ExtraSamples::AssociatedAlpha) | Some(ExtraSamples::UnassociatedAlpha) => true,
             // In lenient mode, keep unspecified alpha interpretation logic compatible with libtiff
             // See Issue #341