Paul, Here are the latest quaternions and the X0,Y0,R0 parameters that I have been using. The thetaX/thetaY bounds are a little different for each camera, but I figured you didn't really care about that kind of stuff since they don't affect ccd to sky conversions. Aaron !! camera 1 quaternions [-28.5,70.4,-21.5] qcam(1,1) = -0.237689D0 qcam(1,2) = 0.467706D0 qcam(1,3) = 0.848236D0 qcam(1,4) = 0.0724612D0 !! quaternions for camera 2 (e1=-86.10, e2=59.05, e3=-6.75) qcam(2,1) = -0.268131D0 qcam(2,2) = 0.0170381D0 qcam(2,3) = 0.962053D0 qcam(2,4) = 0.0476403D0 !! quaternion for camera 3 [-143.3, 63.43, -0.42] qcam(3,1) = 0.203781D0 qcam(3,2) = 0.437286D0 qcam(3,3) = -0.869462D0 qcam(3,4) = -0.106259D0 data yoffset /0.,65.,59.,61.,55./ data xoffset /0.,1.,1.,1.,1./ data x00 /630.D0,634.D0,628.7D0,637.7D0,633.D0/ data y00 /1291.38D0,1306.1D0,1297.1D0,1304.9D0,1294.3D0/ if(ic.eq.1) r0=1193.5D0 if(ic.eq.2) r0=1188.5D0 if(ic.eq.3) r0=1198.5D0 x0(ic+1)=x00(ic+1)-xoffset(ic+1) y0(ic+1)=y00(ic+1)-yoffset(ic+1)