Hi Jianhao, You have to untick the “cap high values at box faces” to see surfaces bellow 0 threshold. You can find this option in Volume Viewer -> Features -> Surface and Mesh options at the bottom of the panel. Best regards, Gabor --- Gabor Papai IGBMC Integrated Structural Biology 1, rue Laurent Fries, Bp 10142 67404 Illkirch, France Tel: +33-3-69485288 On 1 Dec 2017, at 4:43 , C.J. <biocjh@gmail.com<mailto:biocjh@gmail.com>> wrote: Hi specialists, I have a problem when adjusting the level of a map. If the level > 0, it seemed OK, but when it is less than 0, it showed a solid box. This is different from EMAN2. In EMAN2, the threshold less than 0 also works. I'm not sure whether the defining of level is the same as the threshold in EMAN2. Or is there any other way to show the density of a map as in EMAN2 with threshold less than 0? Some snapshots of the visualization in both programs are attached to the post. Thank you! regards, Jianhao <7a.png><7b.png><10a.png><10b.png>_______________________________________________ Chimera-users mailing list: Chimera-users@cgl.ucsf.edu<mailto:Chimera-users@cgl.ucsf.edu> Manage subscription: http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-users