Hum, OPT_CUSTOM_GAMMA is wrongly set to SANE_CAP_INACTIVE by default, so you can't use gamma tables ... I'll commit a fix by tomorrow. Meanwhile you can edit umax_pp.c and remove '| SANE_CAP_INACTIVE' on the line : dev->opt[OPT_CUSTOM_GAMMA].cap |= SANE_CAP_ADVANCED | SANE_CAP_INACTIVE; OPT_UTA_CONTROL has the same problem. With this, both options will show up advanced options of xscanimage. Regards, Stef