[normhead]

Yet Pentax , with more mechanical parts, led both Canon and Nikon in dependability for years? How is that possible?

[Nicolas06]

Electronic parts are actually more dependable than mechanical parts. Look at the issue Pentax had with the aperture actuators on the K-xx series. Yes, there is one other thing that can fail, but one less mechanical thing that can fail. Personally, I prefer a mechanical aperture, because a mechanical failure can be fixed fairly easily, parts not in production can be 3d printed or had from a doner lens where as good luck fixing the circuitry in a fully electronic lens. Plus, a fully electronic mount makes macro a pain, there has got to be nothing as annoying as using a canon lens with a dumb extension tube, and ones that communicate with the lens are stupid expensive.

Some electronic component are extremely durable, some other are not. It really depend. A chip like a processor can last a very long time and is very unlikely to fail. What fail typically in electronics as an example are power capacitors, in particular if you don't spend enough money on them. But it also seems that lot of mechanical things controlled by electronics are prone to failure too.

In the end that always a mater of price and design. Getting a car, even mostly mechanical to still be in good shape after 1000 000 kms is almost impossible. But for trucks it is common.

I don't think this is linked so much to mechanical or electronics part than fitting the design/specifications. We know clearly that a K30/K50 life expectency isn't the same as K5 or K3. Like we know that SDM of 16-50 is to be avoided while lenses like 18-135 look to work flowlessly.

Sure as the PLM motor for Pentax is new and KAF4 is new too, there more risk of an unknow design issue but the first problem is likely that it is not built to the same standard as a DFA70-200 rather than the technology used.

[Kunzite]

The interesting thing is that this 55-300 RE PLM introduces 2 new (to Pentax) technologies: the electromagnetic aperture and the PLM autofocusing system.
I wonder if they'll test these for a while (to avoid a SDM-like incident - since it was the first 2 SDM lenses which damaged the reputation for all of them), or they're confident enough to follow with more lenses having these technologies in 2017.

[pacu]

Yet Pentax , with more mechanical parts, led both Canon and Nikon in dependability for years? How is that possible?

High quality components.

Yet some batches of Pentax lenses have issues with quality control, de-centering.

[Nicolas06]

The interesting thing is that this 55-300 RE PLM introduces 2 new (to Pentax) technologies: the electromagnetic aperture and the PLM autofocusing system.
I wonder if they'll test these for a while (to avoid a SDM-like incident - since it was the first 2 SDM lenses which damaged the reputation for all of them), or they're confident enough to follow with more lenses having these technologies in 2017.

If it is like where I work, some would want to test carefully and be cautious, while some other would be for rushing 10 more lenses with the same technology based on the early success. The first one are typically engineers, the second one are typically marketing guys or people hoping for a bigger yearly bonus.

I guess you need both opinon to not be either too cautious or too risky!

[normhead]

High quality components.

Yet some batches of Pentax lenses have issues with quality control, de-centering.

Read the lens rental reports on those things. No camera company is immune from that, and everyone else is just as and. Even$10,000 Canon and Nikon telephotos arrive de-centered from time to time. It's not just a Pentax issue, you have to assume the cost of avoiding de-centering would out-weigh the benefits to the camera companies. Lens Rentals reports that most companies don't even have the equipment to test for and correct de-centering.

[reh321]

Yet Pentax , with more mechanical parts, led both Canon and Nikon in dependability for years? How is that possible?

The Indy 500 started off in 1911 to show that an automobile could make a 500 mile trip; today most of the cars do not have mechanical issues which cause them to drop out early, but experts say that few could complete a race of 2000 miles - and yet, Mack Truck units routinely do that. On the other hand, a Mack Truck would come in last amongst units which were still running when the race ended. There is a big difference between longevity and performance.

[normhead]

The Indy 500 started off in 1911 to show that an automobile could make a 500 mile trip; today most of the cars do not have mechanical issues which cause them to drop out early, but experts say that few could complete a race of 2000 miles - and yet, Mack Truck units routinely do that. On the other hand, a Mack Truck would come in last amongst units which were still running when the race ended. There is a big difference between longevity and performance.

yawn.... I stand in the same parking lot with guys shooting Canon and Nikon....your analogy is crazy. Sometimes I win the "race" to get the best image, sometimes one of them does, SO, ya, if your Mack Truck were capable of winning the race, the analogy would work. But it isn't, so it's nonsense. Its the results that count. Not minor fractions of a second differences in focusing. Focussing in .1 second when .3 would do the same thing. One is 3 times faster than the other, but in most situations they are functionally the same. Let's not get stupid.

Focussing and shooting a 23 shot burst at 8 fps, I might miss one shot my Canikon Compatriots would get, because of slower Pentax focussing. Effectively a 4% difference.

[Fogel70]

The interesting thing is that this 55-300 RE PLM introduces 2 new (to Pentax) technologies: the electromagnetic aperture and the PLM autofocusing system.
I wonder if they'll test these for a while (to avoid a SDM-like incident - since it was the first 2 SDM lenses which damaged the reputation for all of them), or they're confident enough to follow with more lenses having these technologies in 2017.

I believe Pentax underestimated the extra complexity of using dual AF system in their first SDM lenses. I don't think dual AF has been tried by someone else before SDM.

To implement electromagnetic aperture that has been in use for 30+ years do not add much risk, and it has also been in used in numerous of cameras from Pentas/Ricoh before.
PLM motor may not be much risk either as this is basically identical to Canon STM, and the same design is used by many others too (many mirrorless systems have used this type of AF for years).

So Ricoh choose widely used conventional designs for 55-300 RE PLM, which minimize risk of something unexpected to happen.

[thibs]

Known proveb tech is something.
Pentax implementation is another.
A good tech badly implemented will ruin the product.

[normhead]

Known proveb tech is something.
Pentax implementation is another.
A good tech badly implemented will ruin the product.

Well, aren't you just full of joy?

[Kunzite]

I don't know what they were underestimating - and we don't have data regarding Canon's USM and Nikon's AF-S failures, for their very first lenses (I heard a story about Canon USM freezing at their first Olympics, but can't remember the details). Perhaps it's the dual AF, perhaps it's using piezo micromotors with weather sealing, perhaps they used the wrong type of motor.

I hope you're right, and the 55-300 RE PLM proves reliable.

[FantasticMrFox]

While most UK vendors sell this lens for around £400, Amazon UK currently offers it for £249. There is no mention of any discount or special offer/promotion, so I gather this is simply a mistake on their behalf?!

If not - get 'em while they're hot

[Kunzite]

Known proveb tech is something.
Pentax implementation is another.
A good tech badly implemented will ruin the product.

Not written as haiku. Fail.

[Nicolas06]

Read the lens rental reports on those things. No camera company is immune from that, and everyone else is just as and. Even$10,000 Canon and Nikon telephotos arrive de-centered from time to time. It's not just a Pentax issue, you have to assume the cost of avoiding de-centering would out-weigh the benefits to the camera companies. Lens Rentals reports that most companies don't even have the equipment to test for and correct de-centering.

Lens Rental show that high end, expensive lenses have far less dispersion in performance than entry level.

Sure we could find some manufacturer is worse overall, but a big part is also the money you put into it and so how much can be invested in better quality build. There not a single reality like "all pentax lenses" or "all Canon lenses". It depend a lot of the exact model with factor like design issues, batch issues and of course if the product is an entry level with heavy cost saving measure or on the contrary a very expensive one where reliability and consistancy will be highly valued by users.

Many people think that their D3300 is kind of the same as a D5 or that their KS2 the same as K1... A bit naive. Same with lenses.