Optical dot gain (ODG) plays an important role for predicting the color of printed halftones. The detailed knowledge of light scatter within the printing substrate might improve the accuracy of printer models and can reduce the number of required training colors to fit the model to the printing system.We propose an apparatus and method for measuring local anisotropic light scatter within graphic arts paper for predicting ODG. The setup is a modification of existing approaches for a more robust determination of the light's point spread function (PSF). To verify our approach we develop a simplified color prediction model for printed halftones that is based only on the reflectances of the fulltone color and the paper and incorporates the PSF for modeling the ODG. Our experiments show that the accuracy of the model in terms of color differences to the measured colors was improved by considering ODG.