  A discussion of a question, studied earlier by V.Veselago in 1967 and by J.
Pendry in 2000, is given. The question is: can a slab of the material with
negative refraction make a perfect lens? Pendry's conclusion was: yes, it can.
Our conclusion is: no, in practice it cannot, because of the fluctuations of
the refraction coefficient of the slab. Resolution ability of linear
isoplanatic optical instruments is discussed.
