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We present a new algorithm for inverting poorly resolved gravitational lens systems using the maximum entropy method (MEM). We test the method with simulations and then apply it to an 8 GHz VLA map of the radio ring lens MG1654+134. We model the lens as a singular isothermal sphere embedded in an external shear field and find the critical radius of the lens is b=0\9820, the dimensionless shear is \=0. 0771, and the position angle of the shear is \=100\8. These results are consistent with the results obtained by Kochanek (1995) using a complementary inversion algorithm based on Clean.
Wallington et al. (Mon,) studied this question.