Unretouched. Longhorn -what-? I'm not really sure - some kind of wood borer maybe? I found this inch-long beetle by my front door and thought it might make an interesting test of the camera's close-focusing abilities. It hung around by my front door for at least two days - must've liked having its portrait made. ;-)
Update August 19, 2005: While exploring at www.whatsthatbug.com, I came across a photo of a similar beetle and I now believe that this is a Cottonwood Borer (Plectrodera scalator).