I use extra image plane to rendering P pass in Mplay.
In Mplay, the P pass looks good, because it is based on world space, but when I export the image as EXR, and review it in nuke, the P pass change to camera space.

Does anyone know why it happened? and how I can export it correctly?
Thanks for your help

not sure if that's what's happening
P pass is by default in camera space, the difference you may see is MPlay/Render View viewport color correction settings (check bottom color correction toolbar), compared to Nuke viewport color correction, but it's all still in camera space

if you want world space P, you need to transform it in the shader and export as separate variable which you then include in your mantra extra image planes list