Keep in mind that the FireFly Renderer in Poser 5 and Poser 6 had the option to turn "texture filtering" on or off. If you turned it on, textures would look sharper, even in the distance.
 
ThrommArcadia is correct: in Poser 7, this is no longer a user-changeable option. The manual says that tetxure filtering is turned on by default, but I'm seeing blurry textures in my scenes, especially when I compare the same image I rendered in Poser 6.
 
Also, the File > Export (to image) feature has been changed: you can no longer set the compression rate for any file types. I suggest saving the image as Photoshop, and then opening the file in either Photoshop or Paint Shop Pro and using those programs' "Save for Web" command.

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