[jerem1912]

Dear all,


There are plenty of lenses (quite old and also some recent ones) that are available for our Pentax DSLR.

Unfortunately a few years ago, Tamron and Sigma stopped developping and selling lenses for Pentax equipment.


As pieces to repair lenses are generally available for a ~10 years period, I am thinking about the lens reliability.


We can seperate the lens in 3 types:

- Type 1: fully manual lenses
- Type 2: lenses with screw-drived AF
- Type 3: lenses with fast / silent AF (microdrive --> SDM, HSM...)


The first type looks to be the most reliable (I would say the same as for the cars, the less electronic inside, the less likely you are to get into trouble).


Type 3 has many advantages over type 2, but tends to be more "delicate" as it is the case of some generations of pentax SDM lenses.

People have even encountered reappearance issues on 16-50 * SDM lenses...


What are your opinions ?
Do we observe the same fragility for all brands ? (I think that Tamron has not developed VC lenses for the Pentax bodies, then, only SIgma HSM lenses could be considered).

[PKMike]

I'm no authority on lenses, but I do know that personally I have refused to buy certain lenses that are notorious for repeat failures.
I just hope that manufacturers have learned from past problems and produce more reliable products going forward.

[jerem1912]

I'm no authority on lenses, but I do know that personally I have refused to buy certain lenses that are notorious for repeat failures.
I just hope that manufacturers have learned from past problems and produce more reliable products going forward.

I agree with you.

I indeed hope that manufacturers learned from past problems.

I'm also asking this question for a personal reason too.
For some situations, I need lenses with silent AF.At the moment, I only own a 18-135 WR that meets this condition.


So I'm looking for additional "silent" lenses. I think that it would be said that in manual mode, I would never make any noise... but I would certainly never be as fast as the SAFOX AF

I've made a research on the forum and looked at some lens reviews, but I can't find the data and information I'm looking for.

Many of the lenses are on the 2nd hand market only (the amount of discontinuited products is now quite high ).

The idea is as you said to avoid selecting models with a high risk of failure.

[CristiC]

Stop worrying and keep snapping pictures, for as long as the lens is usable.

Normal usage and avoiding careless rough handling will keep the kit working for many years. Regular use is even better than not using it for longer periods. I have had zero AF-related problems since 2012 and still use MF since 1987. I still use a plastic Tamron 28-80mm that is long out of production and screw-driven. If that would fail some day then I will continue to use it on Pentax film cameras such as the Pentax ME Super, that has a split screen viewfinder. Manual focus is easy enough and taking pictures that way is its own kind of fun. I also have several Canon cameras and several Tamron lenses but I would not hesitate to buy another copy of any Pentax lens that I enjoy using (out of 11 that I own), in case one would fail. Which neither did, so far.

[othar]

I only own lenses of type 1 + 2, but it stands to reason, that simpler lens designs are less likely to fail.
That said even fully manual lenses sometimes need repairs. Be it a change of grease for more fluent focusing operations, a non working aperture mechanism, or something challenging like a separated lens element.

Some designs, like the early SDM lenses, are reported to be not that reliable, but that can happen to all brands, when there is a new technology being used.

[ramseybuckeye]

Unfortunately, due to age some older lenses are more prone to sticky apertures, balsam separation, and fungus. We know fungus is normally due the owner taking care of the lenses, I imagine the other problems are too. If you only knew for sure the life of a lens before buying.

[robgski]

Honestly, I've never had an issue with any used Pentax branded lens I have owned, no matter what features it had. Also, most of my used gear purchases have been from other members here on PF Marketplace.

Inspect the lens before you buy it, and try it on your camera if possible.

If the deal sounds too good to be true, it probably is, Caveat Emptor!

[FozzFoster]

idk my 11-18mm is built like a tank haha

[Kerrowdown]

Never had any issues with any of my "Ladies"... apart from the idiot behind the camera.

[Des]

The better quality screw-driven AF lenses tend to be pretty durable. For example, I've got the FA*300 f4.5, which might be 25 years old (I don't know, I got it secondhand) - it's very sturdily built and still going strong (touch wood). I doubt that many copies of the DA*300 f4 will have such a long and healthy life. This is merely anecdotal, but problems with the SDM AF of the DA*300 don't seem to be uncommon. And it wasn't one of the notoriously dodgy SDM lenses like the DA 17-70.

But if you take modern Pentax consumer zooms, while we hear a few horror stories, overall they seem to me to be quite reliable. DC and PLM AF systems in particular have generally proven quite successful and QC seems to be better. If you take the popular DA 18-135, for example, it seems better quality than their F or FA 28-xx counterparts of the film era (not to mention better AF).

The main problem with consumer zooms now is not reliability but durability. I have two copies of the DA 55-300mm f4.5-6.3 PLM. It's my most used lens, and for what it is, it's amazingly good. But I have broken the first copy twice and the second copy once. Each time was an impact which caused it to break off and the base of the barrel. Yes, my fault each time (dropped onto the deck of a boat once, hit the ground when I slipped on a muddy slope once and tripped over the third time), but really it didn't take much force. I'm not complaining - plastic construction is what makes it light weight and affordable - but it shouldn't be seen as a lifetime lens. Same thing for lenses like the DA 16-85 and DFA 28-105. By contrast, the DA 20-40 Limited is like an old time lens - built to last.

[StiffLegged]

Never had any issues with any of my "Ladies"... apart from the idiot behind the camera.

I’m quite sure the Ladies think the same, as do my manual examples.

[Kerrowdown]

I’m quite sure the Ladies think the same, as do my manual examples.

Maybe it's a Scottish lens thing...

[StiffLegged]

Maybe it's a Scottish lens thing...

Aye! My wife and daughter treat me in similar vein…

[thix2112]

Purchased a used DA* 55 1.4 from B&H several months ago. Always have had good luck with B&H used lenses except this one. Arrived with inoperative SDM motor. They took it back no problem but a bit disappointed with the quality check on it at their end.

[Kerrowdown]

Aye! My wife and daughter treat me in similar vein…

So there's hope then... albeit slight.