[yucatanPentax]

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I have a still functioning K-30, possibly the most eligible camera for aperture failure, or at least the first in which many reports accumulated.

Some time ago, PF did a survey and an analysis to determine how many / what percentage were actually failing. This thread is an example of one of the thoughts going into and coming out of that process: Those with a failure are much more likely to publicly post. Those without a failure are very likely shooting photos obliviously, enjoying their cameras and not posting either way.

I think the "best guess" that came out of the K30, K50, KS1, etc reporting and analysis was that maybe about 25% had the failure. My memory may fail me here, so I welcome correction by the powers that be.

My feeling would be to enjoy your camera as much and as often as possible. The "feeeeeeling" is that use helps it stay alive (possibly wishful thinking? how would that be documented?). When it fails, continue to use it with manual aperture lenses. It's perfectly functional. In fact, that's what I enjoy doing a lot of anyway.

Then pick up the latest Pentax and enjoy away some more!

Edit: BTW, if you are concerned about failure while on a trip or something important, bring along manual aperture lenses as well. A couple should suffice. If there's a failure, you can always use those. You mainly lose automatic focus. Being forgetful, if I'm switching a lot, I'll forget to focus carefully again. So, maybe meanwhile, practice using MF / manual aperture lenses as well as AF / auto aperture.

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Last edited by yucatanPentax; 08-08-2022 at 10:00 PM. Reason: added commentary....

[photogem]

Some time ago, PF did a survey and an analysis to determine how many / what percentage were actually failing.
.... Those with a failure are much more likely to publicly post.

I don't think so but actually the opposite:
There have been a few people who registered to this forum because they had the "dark picture syndrome" (ABF)
but most who posted were already members

I believe that most normal users just think their camera is dead, warranty is gone and then they either chuck it or sell it broken.
My observation with over 120 repairs by now is that about 25% of them had been repaired on warranty but during early days got the same earliest China-Solenoid built in, some the 2-nd generation with a smaller magnet.

This view is approved by many members of the German Pentaxians forum: Quite a few had their Pentax (mainly K30/50) repaired and after the 1 yr. warranty failed again.

Those without a failure are very likely shooting photos obliviously, enjoying their cameras and not posting either way.

For those not registered in a forum (vast majority) I'd say yes, but not so for those here in this forum or other forums:
At the beginning when ABF showed up more often there was almost a stampede by some doing everything to play down the fault!
I remember very well.
One thread was THIS ONE
One member even asked a Pentax expert:

Today (10/26/18) I returned from the Photoplus International Conference in Manhattan. I asked two of them what Pentax was doing to address the "aperture block" problem for the K50 camera. I was astounded when they said that they had never heard of it. After I described the symptoms, which consist of major underexposures of photos due to a malfunctioning electromagnet, I was met with blank stares.

I was told to return when the technical expert would be back. When I finally met him and asked about the problem he said he knew of it but that it was a very rare. I'm not sure if he really knew about it or not. Maybe he was just trying to slough me off because he didn't discuss it from a technical standpoint.

I responded that if this rep was really an expert, he didn't tell the truth!

Because in 2018 the problem was very well know, in Germany for example "it hailed K30's and K50's" to be repaired, same in Switzerland and France. I have a personal mail from "THE" Paris Pentax/Ricoh Representative who acknowledged the problem!

In 2016 a member of the German Pentaxians forum started a similar survey. In 2018 the result was:
62% of K30 users had failed solenoids
43% of K50 users had failed solenoids

And just a little bit later on it was even worse (end of 2018, after that until 2022 only 5 members more actually voted)
Final result:
219 K-30 owning Pentaxian-forum-members (hardly any new registered!) voted: 150 of them had ABF, that means 68%
151 K-50 owning Pentaxian-forum-members (again most long-time members) voted: 77 had ABF = 51%

All this became better but actually 60% of my repairs in the past 2 years were K-S1's (and quite a few K-S2's),

but very important: 99% of them manufactured before Dec.2022, so with the earlies China-Solenoid.


I also observed offers on ebay and a German only market for 2-nd hand:
About 80% of all damaged K30/50/500/K-S1/K-S2 offered were described with "suddenly my Pentax produces just dark (or black) photos".
Their owners didn't know about ABF but had it of of course!

The other about 20% did "guess that it would be ABF" and mentioned that one can google about the problem.


It were a lot offered there and at a time there was a run to buy these cheap, repair them (often by just filing or insert the wrong SLR solenoid, some later arrived on my workbench because they failed again) and offer them on ebay with the notion: ABF repaired.

To me it was particular interesting that so many K-S1's failed (but never turned up in any valuable survey).
Because I like the K-S1, it is a really little handy camera and with the DA50 light and cheap enough.
Many students I know bought those as well and repaired them because I gave them a few times lessons how to do it.

I think the "best guess" that came out of the K30, K50, KS1, etc reporting and analysis was that maybe about 25% had the failure. My memory may fail me here, so I welcome correction by the powers that be.

I think "Pre-December 2015 Solenoid-driven Pentax DSLRs" (first generation China-solenoid) we have more than 50% failure!
I am quite certain about this but I can't prove it of course. There are no official numbers.

But I know from one of the best German shops who love and stand by Pentax that "it really hailed K30's and K50's" for repair during the German 2 years warranty-period and later on as well! Particular the K30 which was a hit, it sold like hot-cakes.

They couldn't believe it and they publicly said so in the German Pentaxians forum!

[The Jannie]

As I've written elsewhere, I'm convinced that a lack of "kick" from the box battery is a contributory factor in solenoid failure. Lack of use is also relevant.

[m42man]

Edit: BTW, if you are concerned about failure while on a trip or something important, bring along manual aperture lenses as well. A couple should suffice. If there's a failure, you can always use those. You mainly lose automatic focus. Being forgetful, if I'm switching a lot, I'll forget to focus carefully again. So, maybe meanwhile, practice using MF / manual aperture lenses as well as AF / auto aperture.

Note that you don't have to necessarily lose autofocus. There are plenty of decent lenses which are autofocus AND have aperture rings.

If you do use a manual focus lens, you might like to try Catch-in-Focus - just hold the shutter button down while you adjust focus, and when the camera judges focus has been reached, the shutter will fire. I find this works well for focal lengths of 50mm and greater.

Note also that you can use Av mode with an afflicted (i.e. bad solenoid) camera, when you use the aperture ring. You do need to use appropriate exposure compensation if you aren't shooting wide open though, in order to get correct exposure.

[photogem]

As I've written elsewhere, I'm convinced that a lack of "kick" from the box battery is a contributory factor in solenoid failure. Lack of use is also relevant.

If that would really be the reason, then ALL Pentax DSLR's using a solenoid would be prone to this fault as well.

But this isn't the case!


NONE Pentax (and Samsung equivalents) DSLR prior the K30 (and using the white Japan solenoid for aperture-control) ever failed!

This were:
*ist-D, *istDS, *istDS2, Samsung GX1, Samsung GX2
K10D, K20D, Samsung GX10, GX20
K100D, K110D, K200D, K-m, K-x, K-r

Also since the 3-rd generation China-Solenoid used in the K-70 (the 2-nd generation was only used a short time)
we have no more failures!

So as you call it "kick" from the battery helped for a short time if ABF appeared if the AA-Adapter D-BH109 was used with Eneloops in particular.
But in almost all cases this helped just for a short time because the reason why the plunger of the solenoid stuck was not because of lack of "kick"

but because of a yet too strong holding force which was finally solved with the 3-rd generation China solenoid and possibly a different alloy used for the plunger.


It was us here in this forum who solved the problem and led the Ricoh engineers to the solution, who were groping in the dark for unknow reasons
and tried to solve the problem for quite a long time without real success.


Of course Ricoh could not retreat to the original Japan solenoid because the manufacturer, Shinmei Japan, had moved production (and all machines) from Japan to China for final and thus the only solution was to modify the existing solenoid.

If Ricoh would have trusted the findings here in the forum and taken on measurements of their own (which would have been much easier for them than for any of us) they would have had the chance to compare measurements of the Japan-DSLR-Solenoid with the China solenoid and it would have had to make "BOING" right away...i.e. a short notification to the manufacturer of the solenoid and all would have been solved.
They woke up in 2015 finally and only after a few K70 with the 2-nd generation solenoid failed as well they got it for final which I only can guess that it was in 2020.

[Owltown]

So I’ve read a lot of posts about solenoid failure on K-30s and K-50s. As a proud original owner of a Pentax K-50, should I expect this problem to occur with my camera? I don’t like to tempt fate by asking the question, but are there ways to avoid the problem- constant use, AA batteries, etc. A quick summary for those of us with functioning cameras might help.

Solenoid failed on my K30 at about 25K shutter actuations.

[Chris_K]

My K50 is still good after 6 years and almost 50k on the shutter...

[reh321]

If I bought a model that was known for the solenoid failure then I would buy it expecting it to fail and therefore would only buy it if I had a white solenoid available to repair it if and when it happened, or maybe replace it at the outset to avoid problems at bad moments (such as being away on holiday).

I just purchased a “FA” zoom lens - which allowed me to set aperture at the lens - expecting to need it at some time. It was light enough for me to carry around in my bag. At this point I wouldn’t worry about it - I believe the latest Pentax solution works, so I would simply purchase a K-70 and continue with life; life is too short to worry about it, and the K-70 is relatively inexpensive.

[yucatanPentax]

I don't think so but actually the opposite:
There have been a few people who registered to this forum because they had the "dark picture syndrome" (ABF)
but most who posted were already members

I believe that most normal users just think their camera is dead, warranty is gone and then they either chuck it or sell it broken.

I was simply trying to recall from memory what the PF Survey project had determined. Memory isn't perfect, but it is true that the PF (rather than Germany) study results were near 25% for K-50s:

Looking at Table 1, we observe that the K-30 was more likely to fail than the K-50, at approximately 37% versus 27%, respectively. Note that K-30 is about a year and a half older than the K-50 and K-30 production stopped at about the same time as the K-50 was launched.

The full survey and results can be found here: Pentax Aperture Block Failure Survey Results

Read in particular the Bias section, which begins like this:

Bias

As with any survey, bias can skew our results away from actual trends in the larger camera population. The key bias in our case is nonresponse bias, as disgruntled users as well as Pentax fans were more likely to respond to the survey than happy users or those who aren't as tech-savvy. To put things in perspective, our records show that we have at least 1799 K-50 owners and 2659 K-30 owners on the forum, so overall survey participation was at most 10% of our user base.

The original survey and subsequent discussion thread is found here: Survey with shutter count and aperture block or shutter failure

My purpose for this comment is not to contradict Photogem who likely has more experience with these repairs and the analysis of the problem that several of us added together, but simply to share the source of my thinking and share the information gathered here on PF after many many discussion threads.

This was the information available to me (in the back of my mind) when I made my comment. I think the PF survey was as well done as one could have been at the time. The consideration of the results and evaluation of the biases seem reasonable and rational.

[slartibartfast01]

I was simply trying to recall from memory what the PF Survey project had determined. Memory isn't perfect, but it is true that the PF (rather than Germany) study results were near 25% for K-50s:







The full survey and results can be found here: Pentax Aperture Block Failure Survey Results



Read in particular the Bias section, which begins like this:







The original survey and subsequent discussion thread is found here: Survey with shutter count and aperture block or shutter failure



My purpose for this comment is not to contradict Photogem who likely has more experience with these repairs and the analysis of the problem that several of us added together, but simply to share the source of my thinking and share the information gathered here on PF after many many discussion threads.



This was the information available to me (in the back of my mind) when I made my comment. I think the PF survey was as well done as one could have been at the time. The consideration of the results and evaluation of the biases seem reasonable and rational.

Of course the PF survey was 6 years ago and K-50 cameras are still suffering solenoid problems for the first time. I wonder what a new survey would show.

[m42man]

Here's an interesting question:

Has anyone any experience of a K-30, K-50 or K-500 which has been left unused for 6 months or more, and which doesn't now suffer from aperture solenoid failure?

[photogem]

I was simply trying to recall from memory what the PF Survey project had determined. Memory isn't perfect, but it is true that the PF (rather than Germany) study results were near 25% for K-50s:

The difference in results is logical and pretty obvious:

The German Pentaxians Survey started 2/2016 and went with 95% of all votes unit 12/2018 so we have a survey of almost 3 years!


The survey here in the Pentaxforum went for about 3 month and was ONLY in the year 2016:
Is started 7/2016 and ended approx. 9/2016, the final result was published [url=https://www.pentaxforums.com/articles/photo-articles/pentax-aperture-block-failure-survey-results.html]9/2016]
So we have a very short period of about


3 month versus 34 month!

My own observations show very clearly, that my guess that over 50% of all K-30 failed and almost 50% of all K50's and K500's (all K500's worldwide were manufactured before 12/2015!) is pretty relalistic.

And I would add that it hit over 50% of all K-S1's!
Just that K-S1's were purchased often by youngsters who ... when contronted with ABF in most cases will just be pissed off and chuck the "bloody thing"... I am not exaggerating but this is based on what I observed.... 95% of all K-S1's were manufactured before 12/2015, I never ever had a K-S1 manufactored after that date in my hands... and I had many.

So I will add at least 30% of all K-S2's because most K-S2's were manufactured before 12/2015 as well.

All this changed very positivly with the K-70, there were only a very few early K-70's which failed
and Ricoh very quickly "got it" and did the right mods and solved it.


As the K-70 is very popular, sold "like hotcakes" as well as did the K-30...

and.... the K-70 is much longer on the market... this is really good news because I haven't heard of any K70 fail for a long time.

There was a survey on the German Pentaxians-Forum for the K-70 as well:
44 no fault (but actually one later got it)
14 had ABF (11 with their 1st K70, 3 with their 2-nd)

This means 24% of those early-manufactured K70's failed and developed ABF.
Almost all votes from 7/2017 until 3/2019 (one last entry in 2022 but the K70 was an early one!)
This means from 3/2019 no more entries.

Actually there were 2 further K70's from a member there. He didn't vote but sent them to me for repair.
That would make it 26%.
Both manufactured in 2017.
He sent me

2 x K70
3 x K30
2 x K-S1 for repair!

All of them ABF but... he never lost trust into Pentax, he loves them and never ever had grudges.

[yucatanPentax]

Here's an interesting question:

Has anyone any experience of a K-30, K-50 or K-500 which has been left unused for 6 months or more, and which doesn't now suffer from aperture solenoid failure?

My K-30 has gone longer than six months and still works fine. Just checked it today after seeing this. I have a variety of bodies so, being one of the lesser capable, gets less rotation than it once did.

It's an interesting point. I'm not sure how a larger scale survey would be done on those terms.

---------- Post added 08-12-22 at 12:03 AM ----------

The difference in results is logical and pretty obvious:

The only difference I'd add to your extensive commentary is this caveat: "of those responding to the survey."

That is, we cannot definitively say, "50% of all K-xx cameras failed."

We can only say "Of those responding to the survey, we know that 50% of all K-xx cameras failed," but cannot say that "50% of all K-xx cameras manufactured failed" because we do not have that information.

The difference is whether people are involved in Pentax groups around the world or whether they are simply using their cameras without joining an online group. Those who seek out groups and group experiences is not the same as all Pentax owners. What the delta between "forum members" and "all owners" would be is anyone's guess. I haven't seen that firm numbers have been released for sales figures around the world.

Again, it is entirely possible that the surveys are an accurate reflection of the global experience. However, it is also true that they may not be fully representing the whole universe of experiences. We simply don't know. As the PF survey report mentions, bias has to be accounted for. That's true with every type of survey.

Self-reporting surveys are not scientific models with sufficient random sampling to confidently represent the whole universe. This is true for any survey of this type.

[nicolpa47]

Here's an interesting question:

Has anyone any experience of a K-30, K-50 or K-500 which has been left unused for 6 months or more, and which doesn't now suffer from aperture solenoid failure?

I can't answer the question directly. I own both a K30 and a K50. Both have been replaced in regular use by later cameras, but I keep them as reserves. The K50 suffered ABF and I repaired it with a white solenoid which continues to work correctly. Prior to the failure both cameras were used for one or two shots every week, which didn't stop the K50 failure. Since doing the repair on the K50 I have been less regular in checking the K30 but, so far, after well over a year or more, it continues to work correctly when asked.

[photogem]

.... The only difference I'd add to your extensive commentary is this caveat: "of those responding to the survey."
.....

We can only say "Of those responding to the survey, we know that 50% of all K-xx cameras failed,"...

That's why I wrote:

In 2016 a member of the German Pentaxians forum started a similar survey. In 2018 the result was:
62% of K30 users had failed solenoids
43% of K50 users had failed solenoids

And just a little bit later on it was even worse (end of 2018, after that until 2022 only 5 members more actually voted)
Final result:
219 K-30 owning Pentaxian-forum-members (hardly any new registered!) voted: 150 of them had ABF, that means 68%
151 K-50 owning Pentaxian-forum-members (again most long-time members) voted: 77 had ABF = 51%

That is, we cannot definitively say, "50% of all K-xx cameras failed."
....
but cannot say that "50% of all K-xx cameras manufactured failed" because we do not have that information.

That's why I wrote:

I think "Pre-December 2015 Solenoid-driven Pentax DSLRs" (first generation China-solenoid) we have more than 50% failure!
I am quite certain about this but I can't prove it of course. There are no official numbers.

But I know from one of the best German shops who love and stand by Pentax that "it really hailed K30's and K50's" for repair during the German 2 years warranty-period and later on as well! Particular the K30 which was a hit, it sold like hot-cakes.

They couldn't believe it and they publicly said so in the German Pentaxians forum!

Again, it is entirely possible that the surveys are an accurate reflection of the global experience. However, it is also true that they may not be fully representing the whole universe of experiences. We simply don't know. As the PF survey report mentions, bias has to be accounted for. That's true with every type of survey.

Self-reporting surveys are not scientific models with sufficient random sampling to confidently represent the whole universe. This is true for any survey of this type.

I fully agree.

And yet there are a few different figures which show interesting numbers:
- seller Potmano sold 680 White Japan-DSLR-Solenoids on ebay.com

- Chinese sellers who give numbers sold 720 cheap and very bad Lenovo China-solenoids*
- I myself repaired about 120 Pentax DSLR's with the Japan-DSLR solenoid and I know of many who did so after I tought them.

That makes ca. 1500** who took on the DIY repair... and we know there will be many more.

Remember: DIY repair, i.e. not those repaired by all the official repair-shops!
So I think all those (remarkeable) figures do have some weight.
*Today I could count ca. 50 ebay sellers offering those cheap Lenovo-Solenoids (and only 40% give numbers how many they sold)

There is another huge quantity on Aliexpress and an even larger quantity on Alibaba... that is for large numbers/vendors

** and of course those 720 with the wrong Lenovo-Solenoid will go wrong again, which might disturb numbers
and some might buy the same rubbish again....