Yes, I understand that when using the same pic in more than one material, the most recent change applies to all.  But, even if the most recent mod was to use gamma value from render settings, or maybe custom gamma value: 2.2, if you close the scene and then open it later, some image maps (can't predict which ones) will have been reset to custom gamma value: 1.

     Also, even if you never close the scene, if you send a test render off to a remote node on the network via Queue Manager, when that remote opens the scene to do the render job, it will have some image maps' gamma reset.

     And image maps which get reset may just as likely be feeding only the diffuse/specular sockets.  But even if they are driving transparency, bump, or displacement, it is not correct for Poser to reset them to gamma: 1 after I've set the gamma.  What is correct would be that they remain set with whatever gamma I chose.  An image map defaulting to custom gamma: 1 when first connected to trans/displc/bump is OK -I get Bopperthijs' point- but if I change that gamma, Poser should not reset it when I reopen a scene or send the scene off to Queue.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5