p.1 #2 · Sigma Lens Repair - direct to repair center or go through Sigma?
I had a similar issue with a Sigma macro (also well out of warranty). I went through the head office and they were very helpful and once I sent the lens in they got back to me quickly with a quote. Fixed the specified problems I was having at no charge (lens needed a firmware update, apparently), but they also found some other issues with the lens which they did charge me for. All told, the cost of service was reasonable and they got the repaired lens back in my hands quickly, so I was a happy camper.