Using linear charge-coupled device (CCD) with turntable is a common way to achieve circumferential image acquisition, which has the advantages of large range of scanning and high resolution, but with the shortcoming of low refresh rate. It can effectively increase the refresh rate by double linear CCD simultaneously scanning mode, but it requires a higher image consistency. The element to effect image consistency of the double linear CCD includes imaging heterogeneity, the registration degree of image field and image grey matching. An on line correction method to match the image grey of the double linear CCD is proposed to solve the problem of aperture adjustment at real time of the double linear CCD on the turntable. And the feasibility of the method is verified by experiments, which can be popularized in project engineering.