diff --git a/wpimath/src/main/java/edu/wpi/first/math/estimator/DifferentialDrivePoseEstimator.java b/wpimath/src/main/java/edu/wpi/first/math/estimator/DifferentialDrivePoseEstimator.java
index 6a4bd6ea58..6bfb3e2199 100644
--- a/wpimath/src/main/java/edu/wpi/first/math/estimator/DifferentialDrivePoseEstimator.java
+++ b/wpimath/src/main/java/edu/wpi/first/math/estimator/DifferentialDrivePoseEstimator.java
@@ -4,7 +4,6 @@
 
 package edu.wpi.first.math.estimator;
 
-import edu.wpi.first.math.Discretization;
 import edu.wpi.first.math.MatBuilder;
 import edu.wpi.first.math.Matrix;
 import edu.wpi.first.math.Nat;
@@ -59,7 +58,7 @@ public class DifferentialDrivePoseEstimator {
   private Rotation2d m_gyroOffset;
   private Rotation2d m_previousAngle;
 
-  private Matrix<N3, N3> m_visionDiscreteR;
+  private Matrix<N3, N3> m_visionContR;
 
   /**
    * Constructs a DifferentialDrivePoseEstimator.
@@ -143,7 +142,7 @@ public class DifferentialDrivePoseEstimator {
                 u,
                 y,
                 (x, u1) -> new Matrix<>(x.getStorage().extractMatrix(0, 3, 0, 1)),
-                m_visionDiscreteR,
+                m_visionContR,
                 AngleStatistics.angleMean(2),
                 AngleStatistics.angleResidual(2),
                 AngleStatistics.angleResidual(2),
@@ -164,8 +163,7 @@ public class DifferentialDrivePoseEstimator {
    *     theta]^T, with units in meters and radians.
    */
   public void setVisionMeasurementStdDevs(Matrix<N3, N1> visionMeasurementStdDevs) {
-    var visionContR = StateSpaceUtil.makeCovarianceMatrix(Nat.N3(), visionMeasurementStdDevs);
-    m_visionDiscreteR = Discretization.discretizeR(visionContR, m_nominalDt);
+    m_visionContR = StateSpaceUtil.makeCovarianceMatrix(Nat.N3(), visionMeasurementStdDevs);
   }
 
   @SuppressWarnings({"ParameterName", "MethodName"})
diff --git a/wpimath/src/main/java/edu/wpi/first/math/estimator/MecanumDrivePoseEstimator.java b/wpimath/src/main/java/edu/wpi/first/math/estimator/MecanumDrivePoseEstimator.java
index 0cf7367fb1..c460bd3a52 100644
--- a/wpimath/src/main/java/edu/wpi/first/math/estimator/MecanumDrivePoseEstimator.java
+++ b/wpimath/src/main/java/edu/wpi/first/math/estimator/MecanumDrivePoseEstimator.java
@@ -4,7 +4,6 @@
 
 package edu.wpi.first.math.estimator;
 
-import edu.wpi.first.math.Discretization;
 import edu.wpi.first.math.Matrix;
 import edu.wpi.first.math.Nat;
 import edu.wpi.first.math.StateSpaceUtil;
@@ -54,7 +53,7 @@ public class MecanumDrivePoseEstimator {
   private Rotation2d m_gyroOffset;
   private Rotation2d m_previousAngle;
 
-  private Matrix<N3, N3> m_visionDiscreteR;
+  private Matrix<N3, N3> m_visionContR;
 
   /**
    * Constructs a MecanumDrivePoseEstimator.
@@ -144,7 +143,7 @@ public class MecanumDrivePoseEstimator {
                 u,
                 y,
                 (x, u1) -> x,
-                m_visionDiscreteR,
+                m_visionContR,
                 AngleStatistics.angleMean(2),
                 AngleStatistics.angleResidual(2),
                 AngleStatistics.angleResidual(2),
@@ -165,8 +164,7 @@ public class MecanumDrivePoseEstimator {
    *     theta]^T, with units in meters and radians.
    */
   public void setVisionMeasurementStdDevs(Matrix<N3, N1> visionMeasurementStdDevs) {
-    var visionContR = StateSpaceUtil.makeCovarianceMatrix(Nat.N3(), visionMeasurementStdDevs);
-    m_visionDiscreteR = Discretization.discretizeR(visionContR, m_nominalDt);
+    m_visionContR = StateSpaceUtil.makeCovarianceMatrix(Nat.N3(), visionMeasurementStdDevs);
   }
 
   /**
diff --git a/wpimath/src/main/java/edu/wpi/first/math/estimator/SwerveDrivePoseEstimator.java b/wpimath/src/main/java/edu/wpi/first/math/estimator/SwerveDrivePoseEstimator.java
index 65077cba19..d1b457958d 100644
--- a/wpimath/src/main/java/edu/wpi/first/math/estimator/SwerveDrivePoseEstimator.java
+++ b/wpimath/src/main/java/edu/wpi/first/math/estimator/SwerveDrivePoseEstimator.java
@@ -4,7 +4,6 @@
 
 package edu.wpi.first.math.estimator;
 
-import edu.wpi.first.math.Discretization;
 import edu.wpi.first.math.Matrix;
 import edu.wpi.first.math.Nat;
 import edu.wpi.first.math.StateSpaceUtil;
@@ -54,7 +53,7 @@ public class SwerveDrivePoseEstimator {
   private Rotation2d m_gyroOffset;
   private Rotation2d m_previousAngle;
 
-  private Matrix<N3, N3> m_visionDiscreteR;
+  private Matrix<N3, N3> m_visionContR;
 
   /**
    * Constructs a SwerveDrivePoseEstimator.
@@ -144,7 +143,7 @@ public class SwerveDrivePoseEstimator {
                 u,
                 y,
                 (x, u1) -> x,
-                m_visionDiscreteR,
+                m_visionContR,
                 AngleStatistics.angleMean(2),
                 AngleStatistics.angleResidual(2),
                 AngleStatistics.angleResidual(2),
@@ -165,8 +164,7 @@ public class SwerveDrivePoseEstimator {
    *     theta]^T, with units in meters and radians.
    */
   public void setVisionMeasurementStdDevs(Matrix<N3, N1> visionMeasurementStdDevs) {
-    var visionContR = StateSpaceUtil.makeCovarianceMatrix(Nat.N3(), visionMeasurementStdDevs);
-    m_visionDiscreteR = Discretization.discretizeR(visionContR, m_nominalDt);
+    m_visionContR = StateSpaceUtil.makeCovarianceMatrix(Nat.N3(), visionMeasurementStdDevs);
   }
 
   /**
diff --git a/wpimath/src/main/java/edu/wpi/first/math/estimator/UnscentedKalmanFilter.java b/wpimath/src/main/java/edu/wpi/first/math/estimator/UnscentedKalmanFilter.java
index b1bc4f19cc..ec163a0e8d 100644
--- a/wpimath/src/main/java/edu/wpi/first/math/estimator/UnscentedKalmanFilter.java
+++ b/wpimath/src/main/java/edu/wpi/first/math/estimator/UnscentedKalmanFilter.java
@@ -334,7 +334,7 @@ public class UnscentedKalmanFilter<States extends Num, Inputs extends Num, Outpu
    * @param u Same control input used in the predict step.
    * @param y Measurement vector.
    * @param h A vector-valued function of x and u that returns the measurement vector.
-   * @param R Measurement noise covariance matrix.
+   * @param R Measurement noise covariance matrix (continuous-time).
    */
   @SuppressWarnings({"ParameterName", "LambdaParameterName", "LocalVariableName"})
   public <R extends Num> void correct(
@@ -364,7 +364,7 @@ public class UnscentedKalmanFilter<States extends Num, Inputs extends Num, Outpu
    * @param u Same control input used in the predict step.
    * @param y Measurement vector.
    * @param h A vector-valued function of x and u that returns the measurement vector.
-   * @param R Measurement noise covariance matrix.
+   * @param R Measurement noise covariance matrix (continuous-time).
    * @param meanFuncY A function that computes the mean of 2 * States + 1 measurement vectors using
    *     a given set of weights.
    * @param residualFuncY A function that computes the residual of two measurement vectors (i.e. it
diff --git a/wpimath/src/main/native/cpp/estimator/DifferentialDrivePoseEstimator.cpp b/wpimath/src/main/native/cpp/estimator/DifferentialDrivePoseEstimator.cpp
index 2d919e6ae0..8ec18eb27b 100644
--- a/wpimath/src/main/native/cpp/estimator/DifferentialDrivePoseEstimator.cpp
+++ b/wpimath/src/main/native/cpp/estimator/DifferentialDrivePoseEstimator.cpp
@@ -36,7 +36,7 @@ DifferentialDrivePoseEstimator::DifferentialDrivePoseEstimator(
         u, y,
         [](const Eigen::Matrix<double, 5, 1>& x,
            const Eigen::Matrix<double, 3, 1>&) { return x.block<3, 1>(0, 0); },
-        m_visionDiscR, frc::AngleMean<3, 5>(2), frc::AngleResidual<3>(2),
+        m_visionContR, frc::AngleMean<3, 5>(2), frc::AngleResidual<3>(2),
         frc::AngleResidual<5>(2), frc::AngleAdd<5>(2));
   };
 
@@ -48,9 +48,7 @@ DifferentialDrivePoseEstimator::DifferentialDrivePoseEstimator(
 void DifferentialDrivePoseEstimator::SetVisionMeasurementStdDevs(
     const wpi::array<double, 3>& visionMeasurmentStdDevs) {
   // Create R (covariances) for vision measurements.
-  Eigen::Matrix<double, 3, 3> visionContR =
-      frc::MakeCovMatrix(visionMeasurmentStdDevs);
-  m_visionDiscR = frc::DiscretizeR<3>(visionContR, m_nominalDt);
+  m_visionContR = frc::MakeCovMatrix(visionMeasurmentStdDevs);
 }
 
 void DifferentialDrivePoseEstimator::ResetPosition(
diff --git a/wpimath/src/main/native/cpp/estimator/MecanumDrivePoseEstimator.cpp b/wpimath/src/main/native/cpp/estimator/MecanumDrivePoseEstimator.cpp
index 5d6967e3ea..ef086bd73e 100644
--- a/wpimath/src/main/native/cpp/estimator/MecanumDrivePoseEstimator.cpp
+++ b/wpimath/src/main/native/cpp/estimator/MecanumDrivePoseEstimator.cpp
@@ -38,7 +38,7 @@ frc::MecanumDrivePoseEstimator::MecanumDrivePoseEstimator(
         u, y,
         [](const Eigen::Matrix<double, 3, 1>& x,
            const Eigen::Matrix<double, 3, 1>&) { return x; },
-        m_visionDiscR, frc::AngleMean<3, 3>(2), frc::AngleResidual<3>(2),
+        m_visionContR, frc::AngleMean<3, 3>(2), frc::AngleResidual<3>(2),
         frc::AngleResidual<3>(2), frc::AngleAdd<3>(2));
   };
 
@@ -53,9 +53,7 @@ frc::MecanumDrivePoseEstimator::MecanumDrivePoseEstimator(
 void frc::MecanumDrivePoseEstimator::SetVisionMeasurementStdDevs(
     const wpi::array<double, 3>& visionMeasurmentStdDevs) {
   // Create R (covariances) for vision measurements.
-  Eigen::Matrix<double, 3, 3> visionContR =
-      frc::MakeCovMatrix(visionMeasurmentStdDevs);
-  m_visionDiscR = frc::DiscretizeR<3>(visionContR, m_nominalDt);
+  m_visionContR = frc::MakeCovMatrix(visionMeasurmentStdDevs);
 }
 
 void frc::MecanumDrivePoseEstimator::ResetPosition(
diff --git a/wpimath/src/main/native/include/frc/estimator/DifferentialDrivePoseEstimator.h b/wpimath/src/main/native/include/frc/estimator/DifferentialDrivePoseEstimator.h
index bef76b973e..3a244c300e 100644
--- a/wpimath/src/main/native/include/frc/estimator/DifferentialDrivePoseEstimator.h
+++ b/wpimath/src/main/native/include/frc/estimator/DifferentialDrivePoseEstimator.h
@@ -212,7 +212,7 @@ class DifferentialDrivePoseEstimator {
                      const Eigen::Matrix<double, 3, 1>& y)>
       m_visionCorrect;
 
-  Eigen::Matrix<double, 3, 3> m_visionDiscR;
+  Eigen::Matrix<double, 3, 3> m_visionContR;
 
   units::second_t m_nominalDt;
   units::second_t m_prevTime = -1_s;
diff --git a/wpimath/src/main/native/include/frc/estimator/MecanumDrivePoseEstimator.h b/wpimath/src/main/native/include/frc/estimator/MecanumDrivePoseEstimator.h
index 07568c27f6..0db20c916e 100644
--- a/wpimath/src/main/native/include/frc/estimator/MecanumDrivePoseEstimator.h
+++ b/wpimath/src/main/native/include/frc/estimator/MecanumDrivePoseEstimator.h
@@ -208,7 +208,7 @@ class MecanumDrivePoseEstimator {
                      const Eigen::Matrix<double, 3, 1>& y)>
       m_visionCorrect;
 
-  Eigen::Matrix3d m_visionDiscR;
+  Eigen::Matrix3d m_visionContR;
 
   units::second_t m_nominalDt;
   units::second_t m_prevTime = -1_s;
diff --git a/wpimath/src/main/native/include/frc/estimator/SwerveDrivePoseEstimator.h b/wpimath/src/main/native/include/frc/estimator/SwerveDrivePoseEstimator.h
index e0f0ae2286..6914086faa 100644
--- a/wpimath/src/main/native/include/frc/estimator/SwerveDrivePoseEstimator.h
+++ b/wpimath/src/main/native/include/frc/estimator/SwerveDrivePoseEstimator.h
@@ -101,7 +101,7 @@ class SwerveDrivePoseEstimator {
           u, y,
           [](const Eigen::Matrix<double, 3, 1>& x,
              const Eigen::Matrix<double, 3, 1>& u) { return x; },
-          m_visionDiscR, frc::AngleMean<3, 3>(2), frc::AngleResidual<3>(2),
+          m_visionContR, frc::AngleMean<3, 3>(2), frc::AngleResidual<3>(2),
           frc::AngleResidual<3>(2), frc::AngleAdd<3>(2));
     };
 
@@ -161,9 +161,7 @@ class SwerveDrivePoseEstimator {
   void SetVisionMeasurementStdDevs(
       const wpi::array<double, 3>& visionMeasurementStdDevs) {
     // Create R (covariances) for vision measurements.
-    Eigen::Matrix<double, 3, 3> visionContR =
-        frc::MakeCovMatrix(visionMeasurementStdDevs);
-    m_visionDiscR = frc::DiscretizeR<3>(visionContR, m_nominalDt);
+    m_visionContR = frc::MakeCovMatrix(visionMeasurementStdDevs);
   }
 
   /**
@@ -296,7 +294,7 @@ class SwerveDrivePoseEstimator {
                      const Eigen::Matrix<double, 3, 1>& y)>
       m_visionCorrect;
 
-  Eigen::Matrix3d m_visionDiscR;
+  Eigen::Matrix3d m_visionContR;
 
   units::second_t m_nominalDt;
   units::second_t m_prevTime = -1_s;
diff --git a/wpimath/src/main/native/include/frc/estimator/UnscentedKalmanFilter.h b/wpimath/src/main/native/include/frc/estimator/UnscentedKalmanFilter.h
index 71eac27221..7ad9c24a2a 100644
--- a/wpimath/src/main/native/include/frc/estimator/UnscentedKalmanFilter.h
+++ b/wpimath/src/main/native/include/frc/estimator/UnscentedKalmanFilter.h
@@ -251,7 +251,7 @@ class UnscentedKalmanFilter {
    * @param y Measurement vector.
    * @param h A vector-valued function of x and u that returns the measurement
    *          vector.
-   * @param R Measurement noise covariance matrix.
+   * @param R Measurement noise covariance matrix (continuous-time).
    */
   template <int Rows>
   void Correct(const Eigen::Matrix<double, Inputs, 1>& u,
@@ -290,7 +290,7 @@ class UnscentedKalmanFilter {
    * @param y             Measurement vector.
    * @param h             A vector-valued function of x and u that returns the
    *                      measurement vector.
-   * @param R             Measurement noise covariance matrix.
+   * @param R             Measurement noise covariance matrix (continuous-time).
    * @param meanFuncY     A function that computes the mean of 2 * States + 1
    *                      measurement vectors using a given set of weights.
    * @param residualFuncY A function that computes the residual of two