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OpticalLimits8.0 It is certainly a controversial lens. In terms of sheer depth-of-field power and speed, it is a mediocre lens. However, the quality of the bokeh is second to none (also compared to STF offerings from other manufacturers). The decision should surely be made based on the target application. [...] It is very sharp at T/5.6 and even more so at T/8. If you look hard you may find some lateral CAs.