Hi Henry Out of curiosity, I was setting the CFs of my F5 and trying out CF#4, activating it isolates AF control via the AF start buttons at the back of the camera. When set at this, after obtaining initial focus, and releasing the AF start button and recomposing, thereby removing the AF sensor from the target, you get a not focused signal with the glowing arrows. At this point, tripping the shutter becomes impossible. The only solution to this problem is to set single servo AF to release priority or not to release the AFstart button, using this as an AF lock button. The F100 also has CF#4 to isolate AF activation via the AF start buttons only. Does this mean that the only way touse this is to keep the AFstart button depressed, like an AF lock button. I guess there will be several more custom functions which can be accessed through the Photosecretary II software. Please let me know if you find out anything about this. Thanks. Carlo _________________________________________________________ DO YOU YAHOO!? Get your free @yahoo.com address at http://mail.yahoo.com