imager is not working
You need to turn on imager in viewport toolbar too. This is something new and works differently as in previous versions. Developers seem not to describe new features recently 

CPU – i9 13900KF, 128GB RAM, GPU – RTX 4090
System – Windows 11
My Behance portfolio, Blender plugin FB support group
System – Windows 11
My Behance portfolio, Blender plugin FB support group
Looks like in 15.2.5 this has been fixed and Viewport and Camera imagers work independently.
CPU – i9 13900KF, 128GB RAM, GPU – RTX 4090
System – Windows 11
My Behance portfolio, Blender plugin FB support group
System – Windows 11
My Behance portfolio, Blender plugin FB support group
same question here, 15.2.5 why render is VERY different from preview? i have thicked octane imager i have thicked imager in the view panel (thanks JC i had no idea that they chaneged it this way, very ackward by the way) but rendered image is different from what i see in the previev .... what can be the problem ?
regards
regards
To fix the difference between live preview and final render you need to go to Blender's colour management options and set the Display Device to none. Leave exposure and gamma at Blender's defaults and don't forget to turn on "Octane Imager" check box in camera settings.
CPU – i9 13900KF, 128GB RAM, GPU – RTX 4090
System – Windows 11
My Behance portfolio, Blender plugin FB support group
System – Windows 11
My Behance portfolio, Blender plugin FB support group
No problem dktw. Just replacing the absent ones 

CPU – i9 13900KF, 128GB RAM, GPU – RTX 4090
System – Windows 11
My Behance portfolio, Blender plugin FB support group
System – Windows 11
My Behance portfolio, Blender plugin FB support group