plotCamera: estimateExtrinsics and extrinsics give different poses. Why?

Hello! I am trying to visualize the positions of two cameras with respect to a calibration target. I can use two different codes, one is correct, and the other is wrong. I wonder why this is the case. Can anyone help me with this? Thank you!

I guess the answer lies in the fact that

R1 == camExtrinsics1.Rotation

camExtrinsics1.Rotation ~= camExtrinsics1.R

But I wonder what the difference is between camExtrinsics1.Rotation and camExtrinsics1.R ...

%% Calculate the camera poses via "extrinsics" --> wrong results for the absPoses
[R1, t1] = extrinsics(imagePoints1, worldPoints1, camera_1_parameters);
[R2, t2] = extrinsics(imagePoints2, worldPoints2, camera_2_parameters);
absPose1wrong = extr2pose(rigidtform3d(R1,t1));
absPose2wrong = extr2pose(rigidtform3d(R2,t2));

%% Calculate the camera poses via "estimateExtrinsics" --> correct results for the absPoses
camExtrinsics1 = estimateExtrinsics(imagePoints1,worldPoints1,camera_1_parameters.Intrinsics);
camExtrinsics2 = estimateExtrinsics(imagePoints2,worldPoints2,camera_2_parameters.Intrinsics);
absPose1correct = extr2pose(camExtrinsics1);
absPose2correct = extr2pose(camExtrinsics2);


% R1 == camExtrinsics1.Rotation
% camExtrinsics1.Rotation ~= camExtrinsics1.R


%% =========================================================
%  3D VIEW: TWO CAMERAS + CHARUCO TARGET
% ==========================================================
figure;
plot3(worldPoints1(:,1),worldPoints1(:,2),zeros(size(worldPoints1, 1),1),"*");
hold on
plot3(0,0,0,"g*");

plotcam1wrong = plotCamera(AbsolutePose=absPose1wrong,Size=100,Color="magenta",AxesVisible=true,Label="wrongCam1");
plotcam2wrong = plotCamera(AbsolutePose=absPose2wrong,Size=100,Color="green",AxesVisible=true,Label="wrongCam2");

plotcam1correct = plotCamera(AbsolutePose=absPose1correct,Size=100,Color="blue",AxesVisible=true,Label="correctCam1");
plotcam2correct = plotCamera(AbsolutePose=absPose2correct,Size=100,Color="red",AxesVisible=true,Label="correctCam2");

axis equal
grid on
cameratoolbar('SetMode','orbit');
xlabel("X (mm)");
ylabel("Y (mm)");
zlabel("Z (mm)");

[William Thielicke]

images:

[William Thielicke]

top view

Answer 1

[William Thielicke]

Ok, it seems to be the premultiply / postmultiply issue. If I add this before doing extr2pose, then both approaches are identical:

R1=R1'; %postmultiply --> premultiply

R2=R2';