diff --git a/src/xSTIR/cSTIR/cstir.cpp b/src/xSTIR/cSTIR/cstir.cpp
index 5c8259307..9e102c7b6 100644
--- a/src/xSTIR/cSTIR/cstir.cpp
+++ b/src/xSTIR/cSTIR/cstir.cpp
@@ -910,25 +910,9 @@ void* cSTIR_imageFromAcquisitionDataAndNxNy(void* ptr_ad, int nx, int ny)
 {
 	try {
 		SPTR_FROM_HANDLE(PETAcquisitionData, sptr_ad, ptr_ad);
-		STIRImageData id(*sptr_ad);
-		int dim[3];
-		float vs[3];
-		float is[3];
-		id.get_dimensions(dim);
-		id.get_voxel_sizes(vs);
-		for (int i = 0; i < 3; i++)
-			is[i] = dim[i] * vs[i];
-		int nz = dim[0];
-		float vx = is[2] / nx;
-		float vy = is[1] / ny;
-		float vz = vs[0];
-		shared_ptr<Voxels3DF> sptr_v(new Voxels3DF(IndexRange3D(0, nz - 1,
-			-(ny / 2), -(ny / 2) + ny - 1, -(nx / 2), -(nx / 2) + nx - 1),
-			Coord3DF(0, 0, 0),
-			Coord3DF(vz, vy, vx)));
-		shared_ptr<STIRImageData> sptr(new STIRImageData(*sptr_v));
-		sptr->fill(0.0);
-		return newObjectHandle(sptr);
+		shared_ptr<STIRImageData> sptr_im(
+			new STIRImageData(*sptr_ad, nx, ny));
+		return newObjectHandle(sptr_im);
 	}
 	CATCH;
 }
@@ -1044,4 +1028,4 @@ void* cSTIR_setImageData(const void* ptr_im, size_t ptr_data)
 		return new DataHandle;
 	}
 	CATCH;
-}
\ No newline at end of file
+}
diff --git a/src/xSTIR/cSTIR/include/sirf/cSTIR/stir_data_containers.h b/src/xSTIR/cSTIR/include/sirf/cSTIR/stir_data_containers.h
index 53296f604..ac2cd7173 100644
--- a/src/xSTIR/cSTIR/include/sirf/cSTIR/stir_data_containers.h
+++ b/src/xSTIR/cSTIR/include/sirf/cSTIR/stir_data_containers.h
@@ -593,6 +593,24 @@ namespace sirf {
 			_data.reset(new Voxels3DF(*ad.get_proj_data_info_sptr()));
             this->set_up_geom_info();
 		}
+		STIRImageData
+		(const PETAcquisitionData& ad, const int nx, const int ny, const float zoom=1.F)
+		//! construct image with appropriate sizes for the given PETAcquisitionData
+		/*!
+			The number of z-planes is automatically determined in the STIR
+			implementation (see STIR documentation for VoxelsOnCartesianGrid),
+			but x and y size can be chosen. Voxel sizing is default_bin_size/zoom
+			(again, see STIR documentation for default_bin_size).
+		*/
+		{
+			const Coord3DF origin(0, 0, 0);
+			const Coord3DI sizes(-1, ny, nx);
+			_data.reset(
+				new Voxels3DF(
+					*ad.get_proj_data_info_sptr(),
+					zoom, origin, sizes));
+			this->set_up_geom_info();
+		}
 		STIRImageData(const Image3DF& image)
 		{
 			_data.reset(image.clone());