Hi! thanks, I'm the post's author. I had the same concern you have about finding "just the right lens", but was pleasantly surprised to find the $180 camera/le

Hi! thanks, I'm the post's author. I had the same concern you have about finding "just the right lens", but was pleasantly surprised to find the $180 camera/lens combo linked in the post worked just fine. In fact basically every piece of optics I had in my lab could pass light at 1050nm, and I have a bit of everything from cheap stuff bought over the counter in Shenzhen to brand-name microscopes. I tried lenses from 6 different vendors and they all worked about the same in terms of passing light (but of course the fidelity of the image scales with cost, better lens tolerances are just more expensive). My guess is that uncoated glass should be transparent in the 1050nm band, but some lenses have AR coatings that limit the bandwidth. A lot of my lenses do have AR coating (based on the greenish tint I see in the reflections), but I guess the bandwidth of the coating used on most visible-light lenses is just wide enough for 1050nm to slide through.