Abstract: Objective ZiYuan-3not only provides distortionless standard scenes for sensor corrected products butalso long strip scenes,whose length could extend almost 600km.The long strip scenes are similar tostandard scenes,whose mismatch and elevation errors,introduced by production procedures are ignor-able.A rational function model(RFM)for long strip scenes is provided.The image space affinetransformation is used to eliminate attitude and ephemeris errors in long strip scenes,and sub-pixelorientation accuracy is made available.When ground control points(GCPs)are deployed around thecorners of the survey area,the RMS(root mean square)of the plane and elevation of long strip sceneswas 2.5mand 1.6mrespectively.The accuracy is similar to the single standard scenes.