Nikon Focusing after F5.6/8

[Arden]

Good Morning Everyone, Xin nian kuai le

Recently interested in getting the 50-500mm Sigma N mount supplementing using the CNY pocket money, but my friend told me something regarding Nikon is being built such that its focusing is not as good after F5.6/8 ??? Sigma 50-500mm is a F4.5 - F6.3 Lens.

Please Advise. thanks!

[Poseidon]

Do you mean the focussing doesn't work at F5.6/8 or the picture being out of focus?

Are you talking about manual aperture or auto aperture?

I think what your friend coudl mean is that lenses which have a maximum aperture of F5.6 or lesser may have trouble focussing. This is due to the aperture being too small to let in enough light for the AF to work properly. This applies to any brand of lenses and not Nikon alone.