diff --git a/qpms/__init__.py b/qpms/__init__.py
index 4595639..298e391 100644
--- a/qpms/__init__.py
+++ b/qpms/__init__.py
@@ -5,7 +5,7 @@ from .qpms_c import PointGroup, FinitePointGroup, FinitePointGroupElement, Parti
 from .qpms_p import *
 from .cyquaternions import CQuat, IRot3
 from .cybspec import VSWFNorm, BaseSpec
-from .cytmatrices import CTMatrix, TMatrixInterpolator
+from .cytmatrices import CTMatrix, TMatrixInterpolator, TMatrixGenerator
 from .cytranslations import trans_calculator
 from .cymaterials import MaterialInterpolator, EpsMu, LorentzDrudeModel, lorentz_drude, EpsMuGenerator
 from .cycommon import dbgmsg_enable, dbgmsg_disable, dbgmsg_active, BesselType
diff --git a/qpms/cytmatrices.pyx b/qpms/cytmatrices.pyx
index ada7fba..aa4bd4a 100644
--- a/qpms/cytmatrices.pyx
+++ b/qpms/cytmatrices.pyx
@@ -231,7 +231,7 @@ cdef class TMatrixGenerator:
                 raise ValueError("Something went wrong")
             return
         elif isinstance(arg, BaseSpec): # Make a new CTMatrix
-            tm = CTMatrix(bspec, None)
+            tm = CTMatrix(arg, None)
             if self.g.function(tm.rawpointer(), omega, self.g.params) != 0:
                 raise ValueError("Something went wrong")
             return tm
@@ -243,12 +243,14 @@ cdef class TMatrixGenerator:
     def sphere(outside, inside, r):
         return TMatrixGenerator(__MieParams(EpsMuGenerator(outside),
                     EpsMuGenerator(inside), r))
+    @staticmethod
+    def sphere_asarc(outside, inside, r, *args, **kwargs):
+        return TMatrixGenerator(__AxialSymParams(
+            EpsMuGenerator(outside), EpsMuGenerator(inside),
+            ArcFunction(__ArcSphere(r)), *args, **kwargs))
+    @staticmethod
     def cylinder(outside, inside, r, h, *args, **kwargs):
         return TMatrixGenerator(__AxialSymParams(
             EpsMuGenerator(outside), EpsMuGenerator(inside),
             ArcFunction(__ArcCylinder(r, h)), *args, **kwargs))
-    def sphere_asarc(outside, inside, r, h, *args, **kwargs):
-        return TMatrixGenerator(__AxialSymParams(
-            EpsMuGenerator(outside), EpsMuGenerator(inside),
-            ArcFunction(__ArcSphere(r)), *args, **kwargs))
 
diff --git a/qpms/tmatrices.c b/qpms/tmatrices.c
index d1ce6ee..6d9c309 100644
--- a/qpms/tmatrices.c
+++ b/qpms/tmatrices.c
@@ -26,8 +26,8 @@
 #include <gsl/gsl_integration.h>
 
 // These are quite arbitrarily chosen constants for the quadrature in qpms_tmatrix_axialsym_fill()
-#define TMATRIX_AXIALSYM_INTEGRAL_EPSREL (1e-6)
-#define TMATRIX_AXIALSYM_INTEGRAL_EPSABS (1e-10)
+#define TMATRIX_AXIALSYM_INTEGRAL_EPSREL (1e-5)
+#define TMATRIX_AXIALSYM_INTEGRAL_EPSABS (1e-8)
 
 #define HBAR (1.05457162825e-34)
 #define ELECTRONVOLT (1.602176487e-19)
@@ -511,6 +511,8 @@ complex double *qpms_mie_coefficients_reflection(
   /*
    *  This implementation pretty much copies mie_coefficients() from qpms_p.py, so 
    *  any bugs there should affect this function as well and perhaps vice versa.
+   *
+   *  Compared to mie_coefficients() from qpms_p.py, this has opposite sign.
    */
   QPMS_ENSURE(J_ext != J_scat, "J_ext and J_scat must not be equal. Perhaps you want J_ext = 1 and J_scat = 3 anyways.");
   if (!target) QPMS_CRASHING_MALLOC(target, bspec->n * sizeof(complex double));
@@ -536,8 +538,8 @@ complex double *qpms_mie_coefficients_reflection(
     complex double fi = zi[l]/x_i+dzi;
     complex double fs = zs[l]/x_e+dzs;
     complex double fe = ze[l]/x_e+dze;
-    RV[l] = -((-eta_inv_i * fe * zi[l] + eta_inv_e * ze[l] * fi)/(-eta_inv_e * fi * zs[l] + eta_inv_i * zi[l] * fs));
-    RH[l] = -((-eta_inv_e * fe * zi[l] + eta_inv_i * ze[l] * fi)/(-eta_inv_i * fi * zs[l] + eta_inv_e * zi[l] * fs));
+    RV[l] = (-eta_inv_i * fe * zi[l] + eta_inv_e * ze[l] * fi)/(-eta_inv_e * fi * zs[l] + eta_inv_i * zi[l] * fs);
+    RH[l] = (-eta_inv_e * fe * zi[l] + eta_inv_i * ze[l] * fi)/(-eta_inv_i * fi * zs[l] + eta_inv_e * zi[l] * fs);
   }
 
   for (size_t i = 0; i < bspec->n; ++i) {
@@ -701,6 +703,7 @@ qpms_errno_t qpms_tmatrix_axialsym_fill(
   p.z = qpms_waveimpedance(outside);
   p.z_in = qpms_waveimpedance(inside);
   p.f = shape;
+  p.bspec = bspec;
   const gsl_function f = {tmatrix_axialsym_integrand, (void *) &p};
 
   if (lMaxQR < bspec->lMax) lMaxQR = bspec->lMax;
@@ -721,6 +724,7 @@ qpms_errno_t qpms_tmatrix_axialsym_fill(
     for(size_t i2 = 0; i2 < bspecQR->n; ++i2) {
       // NOTE that the Q', R' matrices are !TRANSPOSED! here because of zgetrs
       const size_t iQR = i1 + i2 * bspecQR->n;
+      double abserr; // gsl_integration_qag() needs this; thrown away for now
       qpms_m_t m1, m2;
       qpms_l_t l1, l2;
       qpms_vswf_type_t t1, t2;
@@ -740,26 +744,26 @@ qpms_errno_t qpms_tmatrix_axialsym_fill(
         p.btype = QPMS_BESSEL_REGULAR;
         p.realpart = true;
         QPMS_ENSURE_SUCCESS(gsl_integration_qag(&f, 0, M_PI, epsabs, epsrel,
-              intlimit, 2, w, &result, NULL));
+              intlimit, 2, w, &result, &abserr));
         R[iQR] = result;
         
         // Im(R')
         p.realpart = false;
         QPMS_ENSURE_SUCCESS(gsl_integration_qag(&f, 0, M_PI, epsabs, epsrel,
-              intlimit, 2, w, &result, NULL));
+              intlimit, 2, w, &result, &abserr));
         R[iQR] += I*result;
 
         // Re(Q')
         p.btype = QPMS_HANKEL_PLUS;
         p.realpart = true;
         QPMS_ENSURE_SUCCESS(gsl_integration_qag(&f, 0, M_PI, epsabs, epsrel,
-              intlimit, 2, w, &result, NULL));
+              intlimit, 2, w, &result, &abserr));
         Q[iQR] = result;
 
         // Im(Q')
         p.realpart = false;
         QPMS_ENSURE_SUCCESS(gsl_integration_qag(&f, 0, M_PI, epsabs, epsrel,
-              intlimit, 2, w, &result, NULL));
+              intlimit, 2, w, &result, &abserr));
         Q[iQR] += I*result;
       }
     }
diff --git a/qpms/tmatrices.h b/qpms/tmatrices.h
index a642011..b39b799 100644
--- a/qpms/tmatrices.h
+++ b/qpms/tmatrices.h
@@ -435,6 +435,11 @@ qpms_arc_function_retval_t qpms_arc_sphere(double theta,
 
 
 /// Replaces T-matrix contents with those of a particle with \f$ C_\infty \f$ symmetry.
+/** 
+ * N.B. currently, this might crash for higher values of lMax (lMax > 5).
+ * Also, it seems that I am doing something wrong, as the result is accurate for sphere
+ * with lMax = 1 and for higher l the accuracy decreases.
+ */
 qpms_errno_t qpms_tmatrix_axialsym_fill(
 		qpms_tmatrix_t *t, ///< T-matrix whose contents are to be replaced. Not NULL.
 		complex double omega, ///< Angular frequency.
diff --git a/tests/tmatrixgens.py b/tests/tmatrixgens.py
new file mode 100644
index 0000000..b5042db
--- /dev/null
+++ b/tests/tmatrixgens.py
@@ -0,0 +1,9 @@
+from qpms import *
+lMax = 3
+spec = BaseSpec(lMax=lMax)
+
+ω = 1.5*eV/ℏ
+
+gensphere_arc = TMatrixGenerator.sphere_asarc(outside=EpsMu(2.3104,1), inside=lorentz_drude['Au'], r=50e-9)
+np.diag(gensphere_arc(spec,ω)[...])
+