" Maybe render the sky with the cloud layers and then brighten the image using an image editor and then use that new image as a background image in another render?" Yes, I could do that but I'm hoping it wouldn't be necessary. I don't have a project or anything where I 'have' to do this. I'm just trying to learn more of the details of Carrara that I haven't had a chance to spend time on up to this point. Frankly, it's no big deal to me if it can't be done within Carrara. The real sky settings not sticking is driving me nuts though ;)