diff --git a/Bahtinov Mask/Bahtinov_Canon_EF_17-40L.scad b/Bahtinov Mask/Bahtinov_Canon_EF_17-40L.scad
new file mode 100644
index 0000000..bb5bd4a
--- /dev/null
+++ b/Bahtinov Mask/Bahtinov_Canon_EF_17-40L.scad	
@@ -0,0 +1,7 @@
+include <_bahtinov.scad>;
+
+daperture=77; // aperture diameter
+focal=120; // focal length of the lens or telescope
+dintcap=85; // internal diameter of the cap
+heightcap=20; // height of the cap(=tcap if flat mask)
+bahtinovfactor=75; // usually 150 to 200
\ No newline at end of file
diff --git a/Bahtinov Mask/Bahtinov_EOS_70-300.scad b/Bahtinov Mask/Bahtinov_Canon_EF_70-300.scad
similarity index 100%
rename from Bahtinov Mask/Bahtinov_EOS_70-300.scad
rename to Bahtinov Mask/Bahtinov_Canon_EF_70-300.scad
diff --git a/Bahtinov Mask/Bahtinov_ST80.scad b/Bahtinov Mask/Bahtinov_Orion_ST80.scad
similarity index 100%
rename from Bahtinov Mask/Bahtinov_ST80.scad
rename to Bahtinov Mask/Bahtinov_Orion_ST80.scad
diff --git a/Bahtinov Mask/Exported/Bahtinov_Canon_EF_17-40L.stl b/Bahtinov Mask/Exported/Bahtinov_Canon_EF_17-40L.stl
new file mode 100644
index 0000000..35287e1
Binary files /dev/null and b/Bahtinov Mask/Exported/Bahtinov_Canon_EF_17-40L.stl differ
diff --git a/Bahtinov Mask/Exported/Bahtinov_EOS_70-300.stl b/Bahtinov Mask/Exported/Bahtinov_Canon_EF_70-300.stl
similarity index 100%
rename from Bahtinov Mask/Exported/Bahtinov_EOS_70-300.stl
rename to Bahtinov Mask/Exported/Bahtinov_Canon_EF_70-300.stl
diff --git a/Bahtinov Mask/Exported/Bahtinov_ST80.stl b/Bahtinov Mask/Exported/Bahtinov_Orion_ST80.stl
similarity index 100%
rename from Bahtinov Mask/Exported/Bahtinov_ST80.stl
rename to Bahtinov Mask/Exported/Bahtinov_Orion_ST80.stl