The early observers never intended that these sunspot drawings be an exact reproduction of spot conditions found on the solar disk. In fact, many of the early drawings were rather crude, lacking the detail found in modern drawings. For the first few years, the drawings were considered only to be a general outline serving as a map to show which spots correspond to the magnetic measurements, and as a reference for additional photographic studies. However, over time a sense of pride developed among the observers, so eventually the drawings evolved into the highly detailed and accurate diagrams seen today, sometimes requiring hours to complete. The sunspot drawing is done in pencil, on a 25.5 by 50 cm pad of white acid-free paper.
Solar north is at the top of the paper, and solar east is to the right-hand side.
This is begun by first aligning the North or South limb of the sun next to a straightedge of the table, then running the telescope drive in its east or west direction. These angles are always recorded in the lower left-hand corner of the archived drawing, but not always included on the website gif image. Next, a Stoneyhurst disk and its holder are placed on alignment holes recessed into the drawing table to keep the holder square to the edges of the table. The Stoneyhurst disk is a circular piece of cardboard drawn to the same diameter as the solar image and equipped with lines of solar latitude and longitude to be used as a reference for sunspot positions. Eighteen different Stoneyhurst disks are used throughout the year to accommodate varying solar B-angles and earth orbital distances from the sun.