Nikon does not charge extra for the 58/1.4g lens and buying this lens is a very personal decision. Why did you buy those 58? If you want great bokeh and blurry rendering. When you want a shallow depth of field and a dreamy look or shine to your portraits. When you need an excellent low light lens. When you need a lens to replace the 50's and 85's in your camera bag. In fact, the last reason does not get the attention it deserves. Not perfect, but this lens can take portraits like the 85 while retaining the versatility of the 50. Sort of like two lenses for the price of one. There are other reasons, but these should suffice. And of course there are a few things to consider. Up close, the DOF is very thin, so I recommend making sure your camera is in good focus. The lens has been widely openly criticized for lack of sharpness. Undoubtedly the lens is sharper at f2, but IMO sharpness isn't an issue that's wide open as long as focus is there. The lens is about the same size and weight as an 85/1.8g and handles and balances beautifully on the D800e. . Focusing speed is fast and consistent in both good and bad light. No complaints. Nikon demands a surcharge of 85/1.8g to 85/1.4g, from 50/1.8g to 50/1.4g, the only question is whether the surcharge for 58/1.4g is worth it and you have to make a decision . I did and am very satisfied.
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