Since 2004, more than 100,000 smoked paper seismograms have been preserved as high‐definition image files in three academic institutes in Japan. Also, 27,000 analog records on 35 mm films of 0.6 m long were converted to tiff files in two institutes. In the process of scanning analog records, we have obtained several tips for the preservation of records. Some records were found and organized in their original places after decades of the archiving process. A few scientific findings for old earthquakes have been obtained using the image files of analog records. Our work induced another project of preserving smoked paper seismograms obtained by government operations in Japan by the same manner. To continue archiving data that are not immediately linked to an increase in the number of research papers at each institute, continuous support such as the international evaluation of the high quality of our archives is fairly important, along with our own ceaseless efforts. To not make future researchers struggle in the same way that we did, it is necessary to foster among seismologists the common traits of data preservation, which astronomers have shared since the sixteenth century.