D5300 & Sigma lenses
If you have a Sigma lens which is more than 6 months old and you buy a new body (eg. D5300), you will find that the lens is not fully compatible. Stabilisation and Live View focussing mightnot work. Contact the Sigma Service Centre. They can update the chip on the lens so that it will talk to the Nikon body. They may do the work under guarantee.