diff --git a/CHANGES.rst b/CHANGES.rst
index 9de551250..57a104961 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -25,6 +25,8 @@ general
 
 - Use tolerance for more comparisons in ``compare_asdf`` [#917]
 
+- Update PSF fitting defaults. [#936]
+
 ramp_fitting
 ------------
 
diff --git a/romancal/lib/psf.py b/romancal/lib/psf.py
index bd2ca74b3..f6f4fe6d2 100644
--- a/romancal/lib/psf.py
+++ b/romancal/lib/psf.py
@@ -58,7 +58,7 @@ def create_gridded_psf_model(
     path_prefix,
     filt,
     detector,
-    oversample=12,
+    oversample=11,
     fov_pixels=12,
     sqrt_n_psfs=4,
     overwrite=False,
@@ -82,7 +82,8 @@ def create_gridded_psf_model(
         Computed gridded PSF model for this SCA.
         Examples include: `"SCA01"` or `"SCA18"`.
     oversample : int, optional
-        Oversample factor, default is 12. See WebbPSF docs for details [1]_.
+        Oversample factor, default is 11. See WebbPSF docs for details [1]_.
+        Choosing an odd number makes the pixel convolution more accurate.
     fov_pixels : int, optional
         Field of view width [pixels]. Default is 12.
         See WebbPSF docs for details [1]_.
@@ -150,17 +151,12 @@ def create_gridded_psf_model(
         if instrument_options is not None:
             wfi.options.update(instrument_options)
 
-        central_wavelength_meters = (
-            filter_central_wavelengths[f"WFI_Filter_{filt}_Center"] * 1e-6 * u.m
-        )
-
         # Initialize the PSF library
         inst = gridded_library.CreatePSFLibrary(
             instrument=wfi,
             filter_name=filt,
             detectors=detector.upper(),
             num_psfs=n_psfs,
-            monochromatic=central_wavelength_meters,
             oversample=oversample,
             fov_pixels=fov_pixels,
             add_distortion=False,