[interested_observer]

OK, I admit up front that there is not one instance of the word "Pentax" in the article. I don't know if that is a bad or good thing, as Lens Rentals probably does not have a hugh stock of Pentax lenses, or that the ones that they have break less often than the others. I have no idea, nor does the article discuses this. Anyway, its an interesting read about the subject.

• LensRentals.com - Assumptions, Expectations, and Plastic Mounts

[delegopa]

Read that too. As someone in the comments already stated, the quality of the used material is often more important than if it's plastic or metal. As long as you dont want to forge with your lenses that is
Pentax is mentioned in the comments and even Mr. Cicala says he is shooting with a K3. Pentax should make him an advertisement offer he can't refuse

[lytrytyr]

The blog makes an important distinction between "mount" and "bayonet".
So as Roger says, you'll often have a metal bayonet attached to a plastic mount.

It's a good idea to have a weak point, like the "plastic mount",
that is designed to be the breaking point.

Like those shear bolts at the base of a street light.

[Colbyt]

Well worth the time to read.

[calculator01]

So I can't take photos of dolphins with my K-3 and 18-135? Bummer.

Good article

[normhead]

I take apart lenses all day every day, so I was rather amazed to find all these facts spoken so dogmatically by people who claimed them to be absolutely true. I make it a rule never to argue with people who claim absolute knowledge, no matter how wrong they are.

This guy is so much smarter than me....

[Canada_Rockies]

So I can't take photos of dolphins with my K-3 and 18-135? Bummer.

Good article

Sure you can. But not under water.

[formercanuck]

The blog makes an important distinction between "mount" and "bayonet".
So as Roger says, you'll often have a metal bayonet attached to a plastic mount.

It's a good idea to have a weak point, like the "plastic mount",
that is designed to be the breaking point.

Like those shear bolts at the base of a street light.

Yup - I agree. Not much different than having a fuse to protect wiring/motors in an electric circuit.
The more 'interesting' point to note - even though most lenses have a metal mount plate, how many lenses are actually NOT made of metal these days. Eg. Sigma 18-200mm DC is pretty much all 'composite' but has a metal mount. I'd expect the mount plate to be screwed into that composite material. The only part that I suspect would take stress (unless its a heavy piece) is the actual neck that the lens twists onto. If the bayonet mount works as expected, there should be little issue.

[reeftool]

The article confirms the old saying "99% of everything is BS". I have always protected my camera and lens in wet weather. It's easy enough to do and I'm not going to press my luck with carelessly exposing my gear to foul weather or other sources of water. That doesn't mean I'm a sunny day shooter. I've shot in every kind of weather that exists. I take my cameras in canoes and kayaks and extended motorcycle trips. It's a simple thing to keep them protected regardless of the "weather resistant" label. From most reports, Pentax has always done a pretty good job but consider that sealing will wear around buttons and dials that have movement and all seals will deteriorate over time. As for the mounts, I agree with the article. It makes no difference. A metal mount screwed into a plastic barrel is no stronger than a plastic mount. While a plastic lens can break when dropped, an all metal lens will dent. Both are bad. Whether a dropped lens gets damaged will depend on the surface it hits and mostly the angle in which it hits along with the distance. It's never good to drop a lens or camera.

[monochrome]

Certain companies have done a marvelous job convincing the market that the words Professional Grade have virtue.

[normhead]

IN answer to the question , what' the difference between an expensive camera and a cheap one, my studio instructor at Ryerson Politech, said "the expensive ones cost more to fix." Add to that the plastic mouth corollary. "Plastic mounts don't damage your lens when they break, metal mounts tear the end of your lens up. And they break with about the same frequency."

More, "things aren't what you think they might be." Stuff. Common sense is a good thing, except when it's wrong.

[dadipentak]

It's never good to drop a lens or camera.

Now you tell me.

[reeftool]

Now you tell me.

I think we've all done it. I've been fortunate that only one lens has been seriously damaged from a drop and that one fell out of my backpack which I had carelessly not checked that if was fully zipped shut. I won't complain about poor build quality if something breaks because I dropped it. If it comes apart under normal use, then that is another story. That happened to an F 35-70 I owned. It's a cheap enough lens to replace.

Yesterday, while shooting some motorcycle ice racing on a local lake, my trusty old K10D gave up the ghost. In mid afternoon, it stopped working with a "memory card error" displayed. Nothing wrong with the card as all cards now display that message but still work in my K5. It has really taken a beating through the years and I think the weather resistant label has lived up to what it implies. I debated selling it a year or so ago. Good thing I didn't because the seller would probably be mad at me and would be likely adding to this thread that weather sealing is a farce. I probably won't get it fixed but just replace it with a used body as that route will be cheaper at this point.

[Canada_Rockies]

Yesterday, while shooting some motorcycle ice racing on a local lake, my trusty old K10D gave up the ghost. In mid afternoon, it stopped working with a "memory card error" displayed. Nothing wrong with the card as all cards now display that message but still work in my K5. It has really taken a beating through the years and I think the weather resistant label has lived up to what it implies. I debated selling it a year or so ago. Good thing I didn't because the seller would probably be mad at me and would be likely adding to this thread that weather sealing is a farce. I probably won't get it fixed but just replace it with a used body as that route will be cheaper at this point.

My K10D is still going strong. I did spend the price of a used one when I cracked the top plate two years ago in a fall. The only lens that I have ever broken was my M 400/5.6, and it is my own fault. I released the quick release plate instead of the ball clamp, and it released very quickly. I cannot really complain about damage. That's it for 52+ years of shooting. I've worn out the shutters, but most of my trades have been for want, not need.