Take some photos of the intersection and explain your position to the judge. Personally, my father did this once and was successful. Worst case is that you will be ordered to pay the fine, and 2 points on your license. If you are not in jeopardy of losing your license as a result of other points already on your license, this is a good way to proceed because the cost of hiring an attorney will signficantly outweigh the fine.
Or if you have not taken the driving school, you could proceed with this route. It is offered online and costs about the same as a fine. And, it keeps the points off.
The above information is the opinion of the author only, and should not be interpreted as legal advice. Should you desire a personal consultation to more fully discuss your facts and legal options available, you may contact my office at 928.775.9398.
Many of the traffic attorneys in the St Louis area only charge $50-75 for the ticket. Hire an attorney and they can get it amended to a non-moving violation, so no points or reason for insurance to increase. The other option, is to fight it, and you may have a good defense.