TWO-DIMENSIONAL DIRECT RECORDING ISOPHOTOMETERS, MICRODENSITOMERTERS AND STEPPING ATTACHMENTS AND PARTS AND ACCESSORIES FOR THE SAME-NAMELY, AUTOMATIC PROGRAMMERS, SPECIMEN TABLE DRIVES, RECORDING TABLE ATTACHMENTS, RECORDING PEN ASSEMBLIES, PEN HOLDERS AND ACTUATORS, PULSE COUNTERS, APERTURE ADJUSTORS, VIGNETTING CONTROLS AND OPTICAL WEDGES, AND RECORDING MEDIA ADAPTED FOR GRAPHIC MARKING FOR USE WITH SAME