We present an experimental method for the in situ observation of directional-solidification fronts in bulk samples of transparent eutectic alloys. The growth front is observed obliquely in dark field through the liquid and a glass wall of the container with a longdistance microscope. We show that a focused image of the whole growth front can be obtained at a certain tilt angle of the microscope. At this tilt angle, eutectic fibers of about 3.5 mu m in diameter can be clearly seen over the whole growth front in 400 Pin thick samples. (c) 2007 Elsevier B.V. All rights reserved.