Sensei Rob wrote:

Fogel70 wrote:

The problem is that plastics is often used for making a product lighter and at lower cost.

From my experience it is plastic parts that most often break, The last three cameras that has broken for me has been because of broken plastic parts. Plastic part just do not seem to last as long as metal parts can.

The last three failures I have had on cameras was because of failure on a plastic part.

- Broken plastic gear in a mirror mechanism

- Broken plastic battery cover

- Crack in plastic body

At least for movable parts, metal seems to be superior to plastics as plastics do not seem to have same life length and wear out faster.

Plastic may work better for fly-by-wire lenses, compared to fully mechanical focus and zoom on DSLR.

I have had numerous of plastic lenses with worn plastic focus and zoom mechanism after a few years leading to increased play and to low friction in the mechanism. Where all metal lenses work fine after 40-50 years.

Plastic can work fine if designed carefully, but it seems that in most cases it seems that low cost is prioritized above life length.

This dude gets it.

Not really. He is merely saying that poorly made and cheap plastics are not as good. The same could be said for metal lenses. I believe the discussion is about plastic barrels and Camera bodies where his concerns are unwarranted. Good design should include high quality plastics where they work best and metal where it works best. The greatest weight savings comes from using plastic for lens barrels and plastic shells for cameras.

--
Tom