Can someone explain to me the difference between a f6.3 reducer and a 0.5x reducer. There is a bit of dollar difference between them. From what I can understand a f6.3 will turn a f10 sct to a f6.3 and a 0.5 will make the same scope a f5. Is this too simplistic?
Also, I think most f6.3 also have field flatteners in their optics, which is ideal for wide field astro photo work, but 0.5x is a plain reducer. Have I got this right?
