I understand how GC works. I don't have a problem with it. I used it already with former Poser Pro versions. :-) But the OP is wondering about something in the settings that may have changed since the last version. hborre writes that Poser 10 is now equipped with GC, the former Poser standard versions were obviously not. So he is right: If the OP wants his render look like they did before he has to set it to 1. That topic sounds familiar from the days when Poser Pro came with GC. But I think the users are better off when they read your manual and use GC. And of course the already mentioned free Scenefixer python script to correct all gamma maps. It's worth it. Poser renders of today don't have to look like in 2006.