Originally posted by Pigeon Actually you are wrong. Fast lenses use larger glass elements with higher precision of manufacturing. They use special glass and they use a lot of it. These lenses really heavy. The same right for the frames. Why do you think these lenses have better resolution and lifetime if they manufactured on the same lines?
Does the economic disaster in Russia improve price of Pentax lenses?
At first, we have no economic disaster :-) We are on a balcony of realtime opera spectacle, looking at you.
And as of glass prices. Read my statements carefully.
Larger glass cost more, but not much (slightly more then weight increase).
If it was the case then 70-300mm lens must cost much more then 18-55mm, as I disassembled both, I can say that first have more then twice amount of glass :-).
"Higher precision of manufacturing" is just nonsense. On today automated lines glass is made not by hand and tolerances are pretty tight (only really crucial medic and large space related optics require high rejection rate). Same for "special alignment" of mass-produced lens. Most of this can be heard from people who never disassembled any lenses.
And as for special glass. Yes, price is higher, but not very much. It is still glass, but with added elements that change refraction.