diff --git a/books/RayTracingInOneWeekend.html b/books/RayTracingInOneWeekend.html
index 578aeb07..562f2cc5 100644
--- a/books/RayTracingInOneWeekend.html
+++ b/books/RayTracingInOneWeekend.html
@@ -1603,7 +1603,7 @@
gives:
- ![Image 11-1](../images/img-1-11-1.jpg)
+ ![Image 11-1](../images/img-1-11-1.png)
@@ -1674,11 +1674,11 @@
to get:
- ![Image 11-2](../images/img-1-11-2.jpg)
+ ![Image 11-2](../images/img-1-11-2.png)
And we can change field of view to get:
- ![Image 11-3](../images/img-1-11-3.jpg)
+ ![Image 11-3](../images/img-1-11-3.png)
@@ -1787,7 +1787,7 @@
We get:
- ![Image 12-1](../images/img-1-12-1.jpg)
+ ![Image 12-1](../images/img-1-12-1.png)
diff --git a/images/img-1-11-1.jpg b/images/img-1-11-1.jpg
deleted file mode 100644
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new file mode 100644
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deleted file mode 100644
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