Hello. I have recently become aware of the relatively inexpensive option of purchasing RH and temp. sensors (known as data loggers) that record environmental data continuously and store it internally in a microchip (ex, ONSET brand). This data is downloaded into a computer at a later time in order for it to be read. The sensors are tiny, and very affordable compared to the recording hygrothermographs that are larger and use graph paper. I believe the data loggers were originally designed for biological studies, field use, and the like. I was wondering if anyone has experience with these loggers in museums. If so, are they worthwhile for museum applications? How do they compare with the "standard" recording hygrothermographs I/we are more familiar with? How is the accuracy of these small units? We are considering them as a cost effective option for a small museum. Any comments are greatly appreciated! Thank you, Rebecca Patchett Lilah C. Holden Elephant Museum Portland, OR e-mail: [log in to unmask]