diff --git a/CMakeLists.txt b/CMakeLists.txt
index b19e91e..e59df60 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 #Specify the version being used aswell as the language
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 3.19)
 #Name your project here
 project(bimsim)
 
@@ -10,7 +10,7 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}")
 find_package(CUDA)
 
 #find OpenCV
-find_package(OpenCV REQUIRED )
+#find_package(OpenCV REQUIRED )
 
 find_package(Boost REQUIRED)
 
diff --git a/FindSTIM.cmake b/FindSTIM.cmake
index bf5762a..c05f9f6 100644
--- a/FindSTIM.cmake
+++ b/FindSTIM.cmake
@@ -1,9 +1,27 @@
+# finds the STIM library (downloads it if it isn't present)
+# set STIMLIB_PATH to the directory containing the stim subdirectory (the stim repository)
+
 include(FindPackageHandleStandardArgs)
 
-set(STIM_INCLUDE_DIR $ENV{STIMLIB_PATH})
+set(STIM_ROOT $ENV{STIM_ROOT})
+
+IF(NOT UNIX)
+    IF(NOT STIM_ROOT)
+        MESSAGE("ERROR: STIM_ROOT environment variable must be set!")
+    ENDIF(NOT STIM_ROOT)
 
-find_package_handle_standard_args(STIM DEFAULT_MSG STIM_INCLUDE_DIR)
+    FIND_PATH(STIM_INCLUDE_DIRS DOC "Path to GLFW include directory."
+            NAMES stim/image/image.h
+            PATHS ${STIM_ROOT})
+ENDIF(NOT UNIX)
+
+find_package_handle_standard_args(STIM DEFAULT_MSG STIM_INCLUDE_DIRS)
 
 if(STIM_FOUND)
-    set(STIM_INCLUDE_DIRS ${STIM_INCLUDE_DIR})
-endif()
+    set(STIM_INCLUDE_DIRS ${STIM_INCLUDE_DIRS})
+elseif(STIM_FOUND)
+	message("STIM library not found. Set the STIM_ROOT environment variable to the STIM location.")
+	message("STIMLIB can be found here: https://git.stim.ee.uh.edu/codebase/stimlib")
+endif(STIM_FOUND)
+
+find_package_handle_standard_args(STIM DEFAULT_MSG STIM_INCLUDE_DIRS)
diff --git a/bimsim.cu b/bimsim.cu
index 2899b2f..7f1289d 100644
--- a/bimsim.cu
+++ b/bimsim.cu
@@ -356,7 +356,7 @@ int main(int argc, char* argv[]){
 		beam.eval(E0, g_Nl);										//evaluate the incident field
 
 		if(g_debug_images && s == 0){
-			stim::filename incident_file = outfile.prefix(outfile.prefix() + "_0_nfi");
+			stim::filename incident_file = outfile.with_prefix(outfile.prefix() + "_0_nfi");
 			E0.image(incident_file.str(), stim::complexMag);
 		}
 		E0.lowpass(stim::TAU / g_lambda * g_NA_obj[1]);				//apply the objective cut-off filter to generate the far-field image
@@ -366,14 +366,14 @@ int main(int argc, char* argv[]){
 		spheres.eval(E, beam, g_Nl, g_MC);
 
 		if(g_debug_images && s == 0){
-			stim::filename nf_file = outfile.prefix(outfile.prefix() + "_1_nfs");
+			stim::filename nf_file = outfile.with_prefix(outfile.prefix() + "_1_nfs");
 			E.image(nf_file.str(), stim::complexMag);
 		}
 
 		E.propagate(g_backprop, stim::TAU / g_lambda);					//propagate the field back to the origin
 
 		if(g_debug_images && s == 0){
-			stim::filename propagate_file = outfile.prefix(outfile.prefix()+"_2_nfprop");
+			stim::filename propagate_file = outfile.with_prefix(outfile.prefix()+"_2_nfprop");
 			E.image(propagate_file.str(), stim::complexMag);
 		}
 
@@ -382,7 +382,7 @@ int main(int argc, char* argv[]){
 		Eff.intensity(I);												//calculate the far field intensity and add it to the single-beam image
 
 		if(g_debug_images && s == 0){
-			stim::filename cropped_file = outfile.prefix(outfile.prefix() + "_3_cropped");
+			stim::filename cropped_file = outfile.with_prefix(outfile.prefix() + "_3_cropped");
 			Eff.image(cropped_file.str(), stim::complexMag);
 		}
 		P = (double)(s + 1) / (double)g_sources.size() * 100;
@@ -396,15 +396,15 @@ int main(int argc, char* argv[]){
 
 	//save the near-field image
 	if (g_debug_images) {
-		stim::filename nearfield_real_file = outfile.prefix(outfile.prefix() + "_3_detector_real");
+		stim::filename nearfield_real_file = outfile.with_prefix(outfile.prefix() + "_3_detector_real");
 		E.image(nearfield_real_file.str(), stim::complexReal);
-		stim::filename nearfield_imag_file = outfile.prefix(outfile.prefix() + "_3_detector_imag");
+		stim::filename nearfield_imag_file = outfile.with_prefix(outfile.prefix() + "_3_detector_imag");
 		E.image(nearfield_imag_file.str(), stim::complexImaginary);
 	}
 	
 	//save the background and single-beam images
-	stim::filename background_file = outfile.prefix(outfile.prefix() + "background");
-	stim::filename intensity_file = outfile.prefix(outfile.prefix() + "intensity");
+	stim::filename background_file = outfile.with_prefix(outfile.prefix() + "background");
+	stim::filename intensity_file = outfile.with_prefix(outfile.prefix() + "intensity");
 
 	if (use_cuda) {
 		stim::gpu2image<float>(I0, background_file.str(), g_R_ff, g_R_ff, stim::cmBrewer);
@@ -419,6 +419,6 @@ int main(int argc, char* argv[]){
 	float* A;
 	HANDLE_ERROR( cudaMalloc(&A, sizeof(float) * g_R_ff * g_R_ff) );
 	gpu_absorbance(A, I, I0, g_R_ff * g_R_ff);
-	stim::filename absorbance_file = outfile.prefix(outfile.prefix() + "absorbance");
+	stim::filename absorbance_file = outfile.with_prefix(outfile.prefix() + "absorbance");
 	stim::gpu2image<float>(A, absorbance_file.str(), g_R_ff, g_R_ff, stim::cmBrewer);
 }
\ No newline at end of file
--
libgit2 0.21.4