Negative Tight Contact Structures on $S^3$

Question

A famous theorem of Eliashberg says that given a positive tight contact form $\lambda$ in $S^3$ there is a diffeomorphism $\Phi: S^3 \to S^3$ such that $$ \Phi^*\lambda = f\lambda_0, $$ where $f: S^3 \to (0,\infty)$ is smooth and $$ \lambda_0 = \frac{1}{2}(\sum_{i = 1}^2x_idy_i - y_idx_i)|_{S^3}. $$ I've never seen negative contact structures on $S^3$ being mentioned. Is there any negative contact structure on $S^3$, and more specifically, is there any tight negative contact structure on $S^3$?