Takahashi FCL
FCL 90 (2000)
You can also found this refractor under the name Sky-90. This refractor looks like FS, but it isnt one of them. Like FSs, the objective is a fluorite doublet with the fluorite lens at the front. The main difference is a large air gasp between the two lens. It is a very fast f/5.5 lens (focal length is 500mm). In option you can found a 1.6x extendeur which convert this refractor into a 90/800 (f/8.9) refractor suitable for planetary work.