ARS | Publication request: COMPARISON OF DROPLET IMAGING SYSTEMS FOR WATER-SENSITIVE CARDS

Submitted to: Aspects of Applied Biology
Publication Type: Proceedings
Publication Acceptance Date: October 13, 2003
Publication Date: January 8, 2004
Citation: Hoffmann, W.C., Hewitt, A.J. 2004. Comparison of droplet imaging systems for water-sensitive cards. Proceedings of Aspects of Applied Biology. 71:463-466.

Interpretive Summary: When water droplets land on water-sensitive cards, a blue stain is created allowing researchers and applicators a method for measuring the droplet size and deposition quality from an application of agricultural chemicals. The objective of this study was to compare the droplet size measured from two different but commonly-used imaging systems from a set of water-sensitive cards collected during an aerial application spray test. The two imaging systems gave very similar results over the range of droplet sizes and measurement parameters tested. The results from this study will allow users of the two imaging systems to be confident that data analyzed with either system can be shared and compared.

Technical Abstract: The imaging of aqueous spray droplets on water-sensitive cards allows researchers and applicators a method for assessing the droplet size spectra and deposition quality from an application of agrochemicals. Two imaging systems (USDA-ARS camera-based system and WRK Inc., DropletScan(TM)) were compared using a set of water-sensitive cards from an aerial application spray test. Although the two systems used different spread factor equations to calculate actual droplet sizes from the stain sizes on the cards and different sample definition and data processing systems, there were high correlations between them for the three droplet size spectra ranges tested (Dv0.1, Dv0.5, and Dv0.9). The information presented in the present paper will allow researchers to be confident that data collected from either system will produce comparable results.