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05-12-2017, 01:50 PM   #556
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Who will participate

QuoteOriginally posted by Will in Seattle Quote
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.
Wrong: As it was written in the survey:

"We e-mailed a survey link to approximately 5000 forum members who reported owning a Pentax K-30, K-50, K-500, K-S1, K-S2, or K-70. The survey was also made available on the forum itself as well as through social media."

You see, owners of those body's have been contacted. The survey shows the results only of those who have been contacted!

Same thing over here in Germany.

Proud owners often are proud to report that all is well.

Best example is moms reporting to kindergarden or school:
In general you will actually get more moms reporting "all is well" then those who will report "that there are problems"!
This is psychology and proud owners of cameras (or cars or guns or knives or trucks or lawnmovers or backing-tins) are pretty much the same.

It is well known that even if somebody has realized somewhere deep down that one has bought something that is not at all up to the real demand, one will change one's own attitude "to make it right".

So I challenge this view that more owners of defunct cameras "will be drawn to participate in such a survey".

But just to point at it again:

Today in ebay Germany: 5 defunct K30's, ebay France: 4 defunct K30's. Speaks for itself.

05-12-2017, 05:22 PM   #557
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Well I think it's perfectly clear it's a significant problem regardless of how sure we can be about the failure rate, which is why I went straight to Ricoh when mine failed.
05-13-2017, 06:59 AM - 1 Like   #558
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QuoteOriginally posted by photogem Quote
Wrong: As it was written in the survey:

"We e-mailed a survey link to approximately 5000 forum members who reported owning a Pentax K-30, K-50, K-500, K-S1, K-S2, or K-70. The survey was also made available on the forum itself as well as through social media."

You see, owners of those body's have been contacted. The survey shows the results only of those who have been contacted!
To be fair, only the results of those who have answered are shown. Which are only about 10% of those being contacted.

QuoteOriginally posted by photogem Quote
Proud owners often are proud to report that all is well.

Best example is moms reporting to kindergarden or school:
In general you will actually get more moms reporting "all is well" then those who will report "that there are problems"!
This is psychology and proud owners of cameras (or cars or guns or knives or trucks or lawnmovers or backing-tins) are pretty much the same.

It is well known that even if somebody has realized somewhere deep down that one has bought something that is not at all up to the real demand, one will change one's own attitude "to make it right".

So I challenge this view that more owners of defunct cameras "will be drawn to participate in such a survey".
Actually, this is very well known in marketing that you hear a lot more from your unhappy customers than your satisfied ones. In the case of the polls we're talking about, for people who haven't had ABF, most of them probably not even know what it is and thus have no idea what the poll is about. Why would they answer a poll if they don't feel concerned by the question or don't understand what it about? On the other hand, people having experienced ABF know about the issue and thus are more inclined to answer a poll they feel is aimed at them... So, long story short, yes these kind of polls tends to overestimate the problem. They're useful, but they must be taken as a highball number. The lowball number would be the number of people reporting the problem on the total number of people contacted. Of course, this suppose all of those who didn't answered didn't had ABF, which will lead to an underestimate. The truth lies somewhere between these two extremes (see my other post above)... From what we know, a rate of 10-15% looks like a realistic bet. Which still represents an unacceptably high failure rate for a single problem...
05-13-2017, 12:14 PM   #559
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QuoteOriginally posted by CarlJF Quote
To be fair, only the results of those who have answered are shown. Which are only about 10% of those being contacted.
Yes, I know, but... as I said, I challenge that more owners of defunct cameras will participate than those who are happy.
What you write here:

QuoteOriginally posted by CarlJF Quote
Actually, this is very well known in marketing that you hear a lot more from your unhappy customers than your satisfied ones. In the case of the polls we're talking about, for people who haven't had ABF, most of them probably not even know what it is and thus have no idea what the poll is about. Why would they answer a poll if they don't feel concerned by the question or don't understand what it about? On the other hand, people having experienced ABF know about the issue and thus are more inclined to answer a poll they feel is aimed at them... So, long story short, yes these kind of polls tends to overestimate the problem. They're useful, but they must be taken as a highball number. The lowball number would be the number of people reporting the problem on the total number of people contacted. Of course, this suppose all of those who didn't answered didn't had ABF, which will lead to an underestimate. The truth lies somewhere between these two extremes (see my other post above)... From what we know, a rate of 10-15% looks like a realistic bet. Which still represents an unacceptably high failure rate for a single problem...
could be for some, but one will never really know.

If I take those polls into account:

K10D: pentax k10d | Camera Shutter Life Database
K20D: pentax k20d | Camera Shutter Life Database
K7: pentax k7 | Camera Shutter Life Database
K200D: pentax k200d | Camera Shutter Life Database
K100D: pentax k100d | Camera Shutter Life Database
K x: pentax kx | Camera Shutter Life Database

one could guess, that actually happy owners are very much willing to participate.
The numbers of defunct cameras is pretty low there, the K5 and K3 are hardly represented,
but we have more defunct bodys here:

K30: pentax k 30 | Camera Shutter Life Database
K50: pentax k 50 | Camera Shutter Life Database

Right now on ebay Germany offered K30's are as such:

5 x defunct
5 x good from private persons
3 x repaired from dealers
2 x good from dealers

Bad K30's where not on offer few month ago, only after this issue + possible repair became very well known through the forums and through reviews on Amazon Germany they are all the sudden on offer. Because for those, who are able to repair it, it is now a very cheap but good camera.

After all, we do not really know and will never find out.

The main reason for my post was to point out that 7% are misleading and complete wrong calculation, particular as it was mentioned,
that those 7% consist of other issues as well and are an average in total. Which tries (misleadingly) to indicate that the total failure of
the K30 might even be lower which is rubbish.

05-20-2017, 12:06 PM - 1 Like   #560
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Hello, I just repaired my K30 with the help of an MZ50 as a donor for the solenoid. I have also some solenoids from CD/DVD rom uinits, but all have 17 ohm resistance comparing to the 30 ohm fount in Pentax cameras. So, I am curious if anybody risked and installed a 17 ohm solenoid? The current through it will be double, so I am afraid the driver might be damaged.
Also is anybody who tried to replace just the metal U part, and keep the original green coil? I am thinking that I could take just the U part from the 17 ohm solenoid.
05-20-2017, 03:36 PM   #561
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QuoteOriginally posted by Yo2lzp Quote
Hello, I just repaired my K30 with the help of an MZ50 as a donor for the solenoid. I have also some solenoids from CD/DVD rom uinits, but all have 17 ohm resistance comparing to the 30 ohm fount in Pentax cameras. So, I am curious if anybody risked and installed a 17 ohm solenoid? The current through it will be double, so I am afraid the driver might be damaged.
Also is anybody who tried to replace just the metal U part, and keep the original green coil? I am thinking that I could take just the U part from the 17 ohm solenoid.
I have a cd rom solenoid and it measures 15 ohm. Could you also just put a resistor in line with it to bring the resistance up to 30? Would a resistor'd solenoid have equal ejecting force as the Pentax one?
05-20-2017, 04:51 PM - 2 Likes   #562
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QuoteOriginally posted by photogem Quote
Yes, I know, but... as I said, I challenge that more owners of defunct cameras will participate than those who are happy.
.
I'd say you're wrong, Photogem.

Negative feedback nearly always outnumbers positive in any field.

An angry minority is motivated to respond, a content majority can't be bothered. It is why the German poll and this forum poll had such poor response rates.

Self-reporting surveys are a failed methodology.


05-20-2017, 05:40 PM   #563
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QuoteOriginally posted by Yo2lzp Quote
Hello, I just repaired my K30 with the help of an MZ50 as a donor for the solenoid. I have also some solenoids from CD/DVD rom uinits, but all have 17 ohm resistance comparing to the 30 ohm fount in Pentax cameras. So, I am curious if anybody risked and installed a 17 ohm solenoid? The current through it will be double, so I am afraid the driver might be damaged.
Also is anybody who tried to replace just the metal U part, and keep the original green coil? I am thinking that I could take just the U part from the 17 ohm solenoid.
This is a great repair, is the MZ50 solenoid a direct replace and solder repair? I have a spare Super ME body, it would have an aperture solenoid unit too I would think and a good one being made in Japan in the 80's. Must look up an exploded diagram!

05-20-2017, 06:43 PM   #564
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QuoteOriginally posted by nocturnal Quote
This is a great repair, is the MZ50 solenoid a direct replace and solder repair? I have a spare Super ME body, it would have an aperture solenoid unit too I would think and a good one being made in Japan in the 80's. Must look up an exploded diagram!
The ME only supports the use of A series lenses by using the aperture ring, The aperture cannot be set by the body itself. Consequently, the aperture lever always attempts to close the lens all the way down. There is no similar solenoid in these older manual focus bodies.
05-20-2017, 09:34 PM   #565
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QuoteOriginally posted by reduno Quote
The ME only supports the use of A series lenses by using the aperture ring, The aperture cannot be set by the body itself. Consequently, the aperture lever always attempts to close the lens all the way down. There is no similar solenoid in these older manual focus bodies.
Thanks, yes I realised that after I posted (brain block)! We would need a body supporting TAV, TV, program mode etc. Maybe all of these legacy bodies don't have a compatible solenoid but a quick check on uk ebay there lists no less than 48 MZ50 bodies for very little money indeed, under 10 etc and the straps/eyecups etc. are handy too, even lenses for a rainy day (no pun intended). I'd be able to fix it too so happy days, the K30 is a great camera with a superb sensor and I've no intention of replacing it for years and years! I've made 30" x 20" prints with it at ISO 500 and no complaints. 😃

My K30 is fine for now, Pentax replaced it outside warranty as the weather sealing failed 😀 which was good of them!
05-22-2017, 04:39 AM   #566
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The MZ50 has a direct replacement solenoid. My question is what about SFX series, these are quite common also.
05-22-2017, 06:14 AM   #567
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Hey all,

Wanted to report back that my repair I made in December finally failed again last week. However, I had the camera apart and the armature unstuck in about 10 minutes. Working fine again now. I'd consider this a temporary fix, but it might buy you 6 months at a time- fine by me.
05-22-2017, 01:36 PM   #568
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QuoteOriginally posted by JayDee Quote
Hey all,

Wanted to report back that my repair I made in December finally failed again last week. However, I had the camera apart and the armature unstuck in about 10 minutes. Working fine again now. I'd consider this a temporary fix, but it might buy you 6 months at a time- fine by me.
Sorry to hear that..what did you replaced first time?
05-22-2017, 04:45 PM   #569
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QuoteOriginally posted by Jeff Lopez Quote
Sorry to hear that..what did you replaced first time?
I filed the armature slightly back in December. I did a little more this time as well.
05-25-2017, 06:27 AM   #570
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QuoteOriginally posted by JayDee Quote
I filed the armature slightly back in December. I did a little more this time as well.
Maybe better to replace it with an MZ50 armature for a more permanent fix?
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