The next step in the authentication of a Krakow overprint is a visual examination of the inking of the individual components on the stamp being examined. The pressure that was applied by the printing press to transfer the ink from the printing plate to the sheet of stamps caused the ink to form sharp edges on the component letters and to display a mottled appearance to the interior of the letters. This is illustrated in Fig. 4 which displays the image of the overprint of Form 1, position 38. The image on the left was generated using a digital camera and the lighting was through the stamp. The sharp edges of the ink on the individual letters can clearly be observed. The image on the right was generated using a scanner and the lighting was reflected light.

The quantity and quality of the ink and the pressure applied by the press on the printing plate varied considerably during the duration of the printing of the overprints. These variations yielded overprints that ranged from very light to excessive inking. It is often difficult to accurately define the overprints on the dark colored stamps.

The next step in the authentication process of an overprint is the detailed comparisons of individual components of the overprint under examination with the overprints from known positions on an overprinted sheet. I have used a Minolta SLR 35mm camera with a macro lens and I have photographed the overprints of all 100 positions of several complete sheets of the overprinted stamps. From the negatives, I have prepared 3 x 5 inch photographs of each position. I have used a Nikon Coolpix 990 digital camera with the film carrier attachment to convert the negatives to digital images. I have also obtained 600 dpi images of these overprinted sheets by the use of a Microtek scanner.

The nature of the typographic components used at that period of time often caused minor defects to occur in individual letters and even the rhombus. This is illustrated in Fig. 5.

These are very clear and definitive identification for these Form 1 positions. Unfortunately, most of the positions have only "fly speck" defects which can easily be missed or filled in with heaving inking of the printing plate. Light inking of the printing plate produces many apparent new defects which are just artifacts of the printing process.