WT5L Blog

I was pretty sure my 11″ Zambuto mirror was due to be stripped and recoated but I had no idea that it was in such bad condition. Here are a couple of photos of the mirror that shows how badly the coating has deteriorated. The photos were made in a dark room with my Canon XSi DSLR. The shots were made at ISO 100, 30 second exposures during which I ‘painted’ the back of the mirror with a red light. The amount of red light ‘leaking’ through the coating is very obvious. Here are two photos of the 11″ mirror (click on images to view larger representations):

As a comparison, here are similar photos of a recently re-coated 8″ mirror: