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A tracking system that stabilizes atmospheric and instrumental image motion at the vacuum tower telescope of the National Solar Observatory at Sacramento Peak and the Kiepenheuer Institut für Sonnenphysik at Tenerife is presented. The system is designed to lock on low contrast features, such as solar granulation (Delta I/I = 0.03 ... 0.05 rms) or other small scale structure. A matrix diode array rapidly scans the scene of interest, usually with a field of 5 arcsec. Images are cross-correlated in real time with a previously recorded reference image of the same area. The drive signal for the image motion corrector, a small, articulated mirror, is generated by measuring the position of the maximum of the cross correlation. Reference pictures are updated every 30 s in order to adapt to the changing small scale solar features. Recent performance tests show that the residual image motion in the tracked image is 0.05 arc sec items compared to a typical 0.5 arc sec it rms for the untracked image. The system locks on any small scale structure anywhere on the sun. The bandwidth of the servo system is approx. 40 Hz, which is sufficient to stabilize image motion on a meter class solar telescope. Varying seeing conditions are handled extremely well by the system. The correlation tracker also includes a seeing monitor providing a relative seeing measure at a two millisecond rate, which can be used for frame selection and shutter control.