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05-11-2017, 03:10 AM   #541
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To me it seems simple: Yes or no? Does the replacement of a green solenoid with a white solenoid render a non-functional camera's aperture system functional and restore the camera to full operational capacity? It seems the fix advocated does that, yes. Unless I'm missing something in these comments?

05-11-2017, 03:12 AM   #542
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QuoteOriginally posted by reh321 Quote
A. We do not know what the actual occurrence rate is. The reported overall failure rate for Pentax is around 7%; since that number includes other issues with other cameras, presumably the failure rate with K-30/50 can be only so high. We don't know whether the actual failure rate is 100% or as low as 5% {and a disproportionate number of the failures end up here}.
Wrong! We do know much more.
Here in Germany, official survey results May 2017:

142 x K30 users participated
82 x K30 users aperture misfunctioning (= 57% damaged)
28 x K30 users had no problems

Survey K50:
88 x K50 users participated
28 x K50 users had damage (= 32% damaged)
60 x k50 users had no problems

The K50 came after the K30 (as did the K500). The survey showed also that more and more K50's are failing.

- Right now every week damaged K30's appear on ebay Germany!

- A dealer in France offers "several" aperture-block-failure K30's on ebay France!

- Every second week or so a damaged K50 turns up.

- Twice I read about a damaged K500 but the K500 was hardly sold, very few are on the market.

- We also know very well that the first cases of damaged K-01 and K-02 appeared.


QuoteOriginally posted by reh321 Quote
B. We do not know whether the K-30/50 are especially at risk. Much of the K-01 innards are said to be the same as those of a K-30, and the K-500 closely related to the K-50, but we don't hear much about those two. I know that a number of regulars here at PF use the K-01, so not hearing about it is especially problematic. {Maybe someone needs to sacrifice one to see what is actually inside}
At least here in Germany we do know that the K30/50 are at risk, same for the K500.

Your speculation on the "mirror-less" K-01 is based on which personal experience?

RiceHigh's Pentax Blog: Inside the K-01
????: PENTAX K-01???????

The K-01 does not have that solenoid in use, the K-01 does not count.
I have one in use, I use it twice a year for traveling very light with just a DA40 limited.
Few weeks ago I opened a damaged K-01, I can't recall spotting a solenoid. Damage was different, it switched off seconds after being switched on.

QuoteOriginally posted by reh321 Quote
C. We do not know whether the triggering variable is shutter count, aperture changes, calendar time, or some other measure. Considerations (A) and (C) are extremely important, because this thread, which started off with your #3, is just a year old - declaring a method to fail is simple, but without knowing the triggering variable, we don't know when to cautiously say that a method is successful. Similarly, we don't know whether using manual lenses, working the aperture control less, would slow or speed potential development of this problem.
You might have a lot of gathered knowledge stored in your head, fine. This is knowledge versus experience.
Experience is what we are after, babble based on guessing is similar like this person who studied all theory about wind-surfing, even wrote books about it.... but then... when... in person, i.e. his body... had to stand the first time on a windsurfer, everybody would see just one thing:
A funny SPLASH


all this goes for your further endless speculations:

QuoteOriginally posted by reh321 Quote
D. We do not know what the underlying cause is. Is the solenoid causing this problem, or is some other part of the system stressing the solenoid.

E. We do not know the difference between solenoids other than a piece of plastic. Perhaps some were made in Japan and some in China, but there is also the possibility that all are made on Taiwan and the change in plastic color is incidental to some other change that occurred at roughly the same time.
SPLASH




---------- Post added 05-11-17 at 03:17 AM ----------

QuoteOriginally posted by MarkJerling Quote
To me it seems simple: Yes or no? Does the replacement of a green solenoid with a white solenoid render a non-functional camera's aperture system functional and restore the camera to full operational capacity? It seems the fix advocated does that, yes. Unless I'm missing something in these comments?
YES!

I have repaired:

4 x K30's
1 x K50

all work (with the white solenoid)

I know at least about 3 other people who undertook this repair here in Germany with the white solenoid:
All went well.
05-11-2017, 03:23 AM   #543
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QuoteOriginally posted by photogem Quote
YES!

I have repaired:

4 x K30's
1 x K50

all work (with the white solenoid)

I know at least about 3 other people who undertook this repair here in Germany with the white solenoid:
All went well.
Thank you. Then those arguing that this solution may not fix the problem appears to be in the wrong.
05-11-2017, 08:13 AM   #544
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QuoteOriginally posted by photogem Quote
Wrong! We do know much more.
Here in Germany, official survey results May 2017:

142 x K30 users participated
82 x K30 users aperture misfunctioning (= 57% damaged)
28 x K30 users had no problems

Survey K50:
88 x K50 users participated
28 x K50 users had damage (= 32% damaged)
60 x k50 users had no problems
It is too bad that the K-30/50 was such a sales disappointment for Pentax. The only way they could maintain the 7% failure rate reported by outsiders would be for the K-30 to be 14% of their sales if nothing else failed, or for the K-50 to be at most 22% of their sales if nothing else failed.

QuoteOriginally posted by photogem Quote
Your speculation on the "mirror-less" K-01 is based on which personal experience?

RiceHigh's Pentax Blog: Inside the K-01
????: PENTAX K-01???????

The K-01 does not have that solenoid in use, the K-01 does not count.
I have one in use, I use it twice a year for traveling very light with just a DA40 limited.
Few weeks ago I opened a damaged K-01, I can't recall spotting a solenoid. Damage was different, it switched off seconds after being switched on.
Personally I had never thought about a connection between the two, until several members here told me that the K-30 was derived from the K-01. If the K-01 didn't pass aperture control on to the K-30, the connection must be much weaker than stated. You should probably correct any one who says that in the future, since I may not be around to do so.

---------- Post added 05-11-17 at 11:15 AM ----------

QuoteOriginally posted by MarkJerling Quote
Thank you. Then those arguing that this solution may not fix the problem appears to be in the wrong.
No, the question is what is the best way to fix the problem. Not enough time has passed to determine how well this method works, and whether old "white" solenoids work better than new "green" solenoids.

05-11-2017, 10:22 AM - 1 Like   #545
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QuoteOriginally posted by reh321 Quote
A. We do not know what the actual occurrence rate is. The reported overall failure rate for Pentax is around 7%; since that number includes other issues with other cameras, presumably the failure rate with K-30/50 can be only so high. We don't know whether the actual failure rate is 100% or as low as 5% {and a disproportionate number of the failures end up here}.
The best data we have are the the ones from the PF Block Aperture failure Survey. Out of 1799 K-50 owners and 2659 K-30 owners, 146 and 261 answered respectively to survey. Of these, 39 K-50 and 96 K-30 had a failure. So, it means failure rate between 2% and 27% for the K-50 and between 4% and 37% for the K-30.

QuoteOriginally posted by reh321 Quote
B. We do not know whether the K-30/50 are especially at risk. Much of the K-01 innards are said to be the same as those of a K-30, and the K-500 closely related to the K-50, but we don't hear much about those two. I know that a number of regulars here at PF use the K-01, so not hearing about it is especially problematic. {Maybe someone needs to sacrifice one to see what is actually inside}
But something is sure, much more K-30 and K-50 were built than the K-500 and K-01. These two models had a very short market life. Again, a look a the Pentax survey reveals that K-30/K-50 represents about 90% of the supposedly affected models (others being K-S1/K-S2/K-500). So, it's just normal that we hear a lot more of the K-30/K-50. It doesn't mean that the others aren't affected by the problem.

QuoteOriginally posted by reh321 Quote
C. We do not know whether the triggering variable is shutter count, aperture changes, calendar time, or some other measure. Considerations (A) and (C) are extremely important, because this thread, which started off with your #3, is just a year old - declaring a method to fail is simple, but without knowing the triggering variable, we don't know when to cautiously say that a method is successful. Similarly, we don't know whether using manual lenses, working the aperture control less, would slow or speed potential development of this problem.

D. We do not know what the underlying cause is. Is the solenoid causing this problem, or is some other part of the system stressing the solenoid.

E. We do not know the difference between solenoids other than a piece of plastic. Perhaps some were made in Japan and some in China, but there is also the possibility that all are made on Taiwan and the change in plastic color is incidental to some other change that occurred at roughly the same time.
The survey also provides insight to these questions. It's clear from the survey data that the failure isn't related to shutter count. It's also obvious that most failures happened within the first three years. Since the K-50 was on the market from 2013 to 2016, we can also deduce that we're actually at the peak for the number of failures. Which fits quite well with the apparent increase in failure that we observe on this forum and others. It also explains why, in both the PF and Germany surveys, the K-30 seems to be more prone to failure than the K-50: it's simply because the K-30 is older by a year.

As for pinpointing the source of the problem, I think only Ricoh could do that, but they're obviously not willing to. However, what we can say for sure is that replacing/repairing the solenoid solves the problem. Photogem provided its own numbers above, and there's also a guy on a French forums who compiles its own results with the same conclusion. I know, these and others are just anectodal evedicence, but they all point to the same direction. So, although we can debate and argue about why it works, for users the only things that matter is that it solves the problem. Maybe the soleind isn't the real or lone cause of the problem. But right now, it's by far the best suspect and it would be surprinsing if it didn't have anything to do with the failure, even if other components might be implicated.

---------- Post added 05-11-17 at 01:41 PM ----------

QuoteOriginally posted by photogem Quote
I have repaired:

4 x K30's
1 x K50

all work (with the white solenoid)

I know at least about 3 other people who undertook this repair here in Germany with the white solenoid:
All went well.
To complement this, I took a look a the numbers from the French Penatx forum I'm talking above for people having tried to repair the solenoid either by filing or replaicng it. So far, six K-30 and 1 K-50 have been saved, with a succes rate of 100%. FWIW, all were manufactured between Aug 23 2013 and Jul 25 2014...
05-11-2017, 11:41 AM - 2 Likes   #546
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QuoteOriginally posted by reh321 Quote
No, the question is what is the best way to fix the problem.
The answer is to replace the solenoid. It works, it restores the camera to 100% operation and is documented so by multiple sources including myself.

QuoteOriginally posted by reh321 Quote
Not enough time has passed to determine how well this method works, and whether old "white" solenoids work better than new "green" solenoids.
How much time would be enough in your mind? Should we all wait? this is a solutions thread not an academic research project.

Surely the objective is to have working cameras again ASAP so we can enjoy them before they become obsolete.
We have reports of replacement green solenoids failing again later.
We do not have reports of replacement white solenoids failing later.
White solenoids appear to work just fine after 20+ years in other cameras.

Put the pieces together and draw your own common sense conclusions.

1000+ new clicks on my K-30 with replacement solenoid. Fix it and enjoy it, don't worry about whether it will be still working in 10 years or not.
05-11-2017, 02:23 PM - 1 Like   #547
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My last comments on the subject, directed to no one in particular. I will not come back to this thread.

The heat generated by this discussion has grown way out of proportion to the subject. My position is simply that if we knew with certainty what caused the problem, then we would know with certainty how to evaluate solutions, but we do not.

Maybe solenoid replacement lasts longer than the solenoid modification which started this thread. Maybe "white" solenoids last longer than "green" ones. The evidence seems to indicate that at least two years of experience is needed to reach any conclusion - unless some method consistently fails before then - and many K-30/50's won't last that long in any case. Although my usual standard has been to declare any camera which lasts less than four years to be a failure, I find myself strongly pulled towards the K-70, so in the next two years I may replace the K-30 I've now had for just twenty-three months regardless of how well it works.

If you are happy with the solution you have picked, that is great. As long as everyone is aware of the various solutions and picks the one s/he is most comfortable with, then I am happy.
05-11-2017, 04:13 PM   #548
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QuoteOriginally posted by reh321 Quote
My last comments on the subject, directed to no one in particular. I will not come back to this thread.

The heat generated by this discussion has grown way out of proportion to the subject. My position is simply that if we knew with certainty what caused the problem, then we would know with certainty how to evaluate solutions, but we do not.

Maybe solenoid replacement lasts longer than the solenoid modification which started this thread. Maybe "white" solenoids last longer than "green" ones. The evidence seems to indicate that at least two years of experience is needed to reach any conclusion - unless some method consistently fails before then - and many K-30/50's won't last that long in any case. Although my usual standard has been to declare any camera which lasts less than four years to be a failure, I find myself strongly pulled towards the K-70, so in the next two years I may replace the K-30 I've now had for just twenty-three months regardless of how well it works.

If you are happy with the solution you have picked, that is great. As long as everyone is aware of the various solutions and picks the one s/he is most comfortable with, then I am happy.
I doubt anyone will want to sit for two years with a broken camera before attempting a fix.

QuoteOriginally posted by caliscouser Quote
How much time would be enough in your mind? Should we all wait? this is a solutions thread not an academic research project.
Well said!

QuoteOriginally posted by caliscouser Quote
The answer is to replace the solenoid. It works, it restores the camera to 100% operation and is documented so by multiple sources including myself.
Seems pretty conclusive evidence to me.

QuoteOriginally posted by CarlJF Quote
However, what we can say for sure is that replacing/repairing the solenoid solves the problem.
As shown by multiple members.

05-11-2017, 08:31 PM   #549
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QuoteOriginally posted by MarkJerling Quote
To me it seems simple: Yes or no? Does the replacement of a green solenoid with a white solenoid render a non-functional camera's aperture system functional and restore the camera to full operational capacity? It seems the fix advocated does that, yes. Unless I'm missing something in these comments?

Yes! For me it worked. I replaced a green solenoid with a green solenoid. Why? As stated previously when I ordered from Ali express the picture showed a white solenoid. On arrival, it was green. For US$15.00 (including postage), with a K-50 that was already disassembled and not wanting to send it back and wait another 3 weeks, I soldered the green solenoid in place. About one month later and last weekend my daughter snapped over 450 shots (she was doing a stop/start animation with her lego) my K-50 still works. For how long I don't know, but it works. And if it works for another 2 years, I will be happy.

I am aware of Ali express and fakes. I live in Hong Kong so am more than aware of fake everything, unless purchased in a reputable store Even then, I have friends that are wary of fakes in reputable stores. It goes with the territory.

I actually was pleased with myself that I replaced the solenoid without stuffing my camera up and will probably do it again in 2 years if I need to. Ricoh dealer in HK offered - parts only HK$900.00, to repair. What colour solenoid would they have replaced the old one with? 15 USD about 120 HKD, for a working K-50 so I'm happy.
05-11-2017, 08:40 PM   #550
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Permenent Magnet (Strong)

Try to magnetized your solenoid..
it works for me.. and I am so happy that right now my camera is working good now
05-12-2017, 12:47 AM   #551
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De-Magnetizing

QuoteOriginally posted by Moises Quote
Try to magnetized your solenoid..
it works for me.. and I am so happy that right now my camera is working good now
Do you mean de-magnetize?

The solenoid is magnetized


Prior exchanging the first solenoid, I did try to de-magnetize the solenoid and the horseshoe, because I felt this could be a possible source.
I hadhave two demagnetizing items here from old audio-days, a "Sumiko Fluxbuster" and a "Namamichi Tapehead Demagnetizer".
I tried both, the Sumiko was a bit complicated, because I had to connect the wires of the Solenoid to an RCA connector and then run the
demagnetizer through it (permanent magnet taken off of course, so only the coils and the iron material is de-magnetized: The Nakamichi is pretty simple to use but cannot demagnetize coils.
One can test this later with a demagnetized screwdriver if any magnetism is gone, it works, the horseshoe did not "stick to the tip of the screwdriver"

But... none of this helped! The solenoid would not work any better!

Few minutes later the white solenoid was installed: Voila!!! It works perfekt.

I believe the filing as well as the "russian method" will work, but I have the suspision, that the permanent magnet in the green solenoid is too strong
plus the precisision which was applied to the manufacture of the white solenoid, anybody who knows how to work with very fine instruments (surgeons for example) can clearly define the difference, butchers of course can't so easely....

So .... all repaired K30/K50 work.

All solenoids taken out of those bodys showed to me very clearly that the horseshoe is "more stuck", sticks tighter and.... moves with less precision inside its counterpart.

More I personally don't need to know. It's enough and... it helped many others.

Sadly I cannot read Russian at all, because there are forums over there where they discussed a lot and I am certain they have found very interesting things. But searching Pentax and Solenoid brought me onto quite a few websites over there.

---------- Post added 05-12-17 at 01:01 AM ----------

QuoteOriginally posted by reh321 Quote
It is too bad that the K-30/50 was such a sales disappointment for Pentax. The only way they could maintain the 7% failure rate reported by outsiders would be for the K-30 to be 14% of their sales if nothing else failed, or for the K-50 to be at most 22% of their sales if nothing else failed.
Typical, I even show you prove that the failure rate of the K30 is much higher (one could even say, right now "it is raining damaged K30's over here in Germany!) you stick like a magnetized horse-shoe to a solenoid to "your 7% failure rate. Concrete?

QuoteOriginally posted by reh321 Quote
Personally I had never thought about a connection between the two, until several members here told me that the K-30 was derived from the K-01. If the K-01 didn't pass aperture control on to the K-30, the connection must be much weaker than stated. You should probably correct any one who says that in the future, since I may not be around to do


I am not interested to correct such nonsense. The K 01 was introduced few month earlier (Febr. 2012) than the K30 (May 2012). Developement took probably a few years, so how on earth should the K30 be derived out of the K-01?



QuoteOriginally posted by reh321 Quote
No, the question is what is the best way to fix the problem. Not enough time has passed to determine how well this method works, and whether old "white" solenoids work better than new "green" solenoids.
Bullshit!

We have the first reports of even Pentax/Ricoh repaired bodys with the orig. green solenoid which failed again.

But not even Peter Gabriel would be able to help you in this case:

So I recommend on those who are not going to be confused by those unfounded useless commentaries:
05-12-2017, 08:10 AM   #552
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Mathematical Miscalculation

QuoteOriginally posted by reh321 Quote
I am a mathematician by education and an engineer by trade, so I have evolved to a combination of wanting to know "why" and wanting to see things actually work; thus I believe this discussion needs to remain aware of what we do not know:

We do not know what the actual occurrence rate is. The reported overall failure rate for Pentax is around 7%; since that number includes other issues with other cameras, presumably the failure rate with K-30/50 can be only so high. We don't know whether the actual failure rate is 100% or as low as 5% {and a disproportionate number of the failures end up here}.

We do not know whether the K-30/50 are especially at risk. .
If you are an educated mathematician, why can you not do an utmost simple calculation based on the easiest mathematical formula, the law of three!

The survey you mention has:

K30 owners: 261, of those 96 had the failure = 36% (very far from your calculated 7%)

K50 owners: 146, of those 39 had the failure = 27% (again, quite far from your calculated 7%)

K500 owners: 11, of those 6 had the failure = 55% (bloody far off your 7%!)

K-S1 owners: 8, no failures reported, hurrey 0% (well, this camera is not yet long on the market but as you know very well, one K-S1 owner showed us his repair!)

K-S2 owners: 22 owners, already 3 failures! That's already 14%, double of your 7%


How do you .... as an educated mathematician, calculate 7% failure?

Even if we make it an average calculation throwing all those into one pot (which is a stupid calculation because it does not take the time since when they are on the market!) we have a 32% failure rate of all reported cameras.

Right now i.e. (today, May 12th):
Just to show how numbers climb up: 5 x aperture-failed K30's on ebay Germany and 4 x on ebay France
05-12-2017, 08:40 AM   #553
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I have read for all cameras, cheaper the price, higher the failure rate which makes sense, and they are on average, 5 to 7%. But the K30/K50 based on photogem's simple sample, but to the point calculation hits it on the head, and can you imagine the ones thru out the world that hasn't made it to the big screen? The failure rate is so high for the k30/K50 that cottage industries are popping up.

What's also interesting, that on average, they fail in the time span of 1 to 2 years, and around 1 K to 3 K shutter activations from what I've read on a couple of forums.

I had a 2nd repair done on my wife's K50, we'll see how long this lasts.
05-12-2017, 10:00 AM   #554
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I come here to see the latest since my K-S2 has it also.
Probably more of that model with the problem will be showing up soon.
05-12-2017, 10:16 AM   #555
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For what is worth, and not that I don't think there's a significant problem here, but to be fair the actual overall failure rate is probably a lot lower than a poll here would show as this isn't a good representation of the ownership group in general. People are drawn here by the failure. I know if my camera hadn't failed I'd be out taking photos instead of looking at polls here.
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