[DenB]

Thanks to all who posted replies to my question. I learned a great deal. In the meantime, I enjoy using my new K-70. I purchased it with the SMCP-DA 35mm f2.8 Macro Limited lens. It turns out to be an excellent partner with the K-70 turning out very pleasing photos. For the record, my version of the K-70 indicates that it was made in the Philippines.

Attached are photos taken the day after I received the K-70. It was a cloudy day, good lighting for flower photos. Can anyone guess where the photos were taken? If so, you get an "A" for the day!

Attached Images

     

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Last edited by DenB; 04-24-2021 at 10:23 AM. Reason: Wanted to add photos to the post.

[VaderSS]

I own a K-30 which started having "Dark Image Syndrome" issues after a couple of years ... around 3000 shots. The camera did not fail; it merely lost its ability to set the lens's aperture correctly, so I purchased a FA 28-105mm to use as its 'standard' lens, because that lens allowed me to set the aperture at the lens. In less than a year, I got a KP when it went on sale on "Black Friday", so I got little use of that system, but it had proven itself by then.

If a camera won't work with the lenses that it is normally packaged with, it has failed. I'm glad you found a workaround though. It is not an acceptable workaround for me.

[mlines]

My 2019 K-70 returns tomorrow, repaired following a failed aperture block.

[reh321]

My 2019 K-70 returns tomorrow, repaired following a failed aperture block.

so, you purchased this K-70 new in 2019, and the repair place diagnosed 'Aperture Block Failure'?
That is earlier than I would expect the "Dark Image Syndrome" to rear its ugly head.

Did you run the PF software
Check Camera Shutter Count and Manufacture Date
on an image to determine shutter count and date of manufacture?

[mtkeller]

so, you purchased this K-70 new in 2019, and the repair place diagnosed 'Aperture Block Failure'?
That is earlier than I would expect the "Dark Image Syndrome" to rear its ugly head.

It’s almost like there’s a broad distribution of times from manufacture to failure because it’s simply a manufacturing flaw in the solenoid and not related to shutter count or the amount of time the camera has sat unused.

[photogem]

It’s almost like there’s a broad distribution of times from manufacture to failure because it’s simply a manufacturing flaw in the solenoid and not related to shutter count or the amount of time the camera has sat unused.

And which studies / experiences did bring you to those findings?

[mtkeller]

And which studies / experiences did bring you to those findings?

Since there’s been no systematic study of the failures, the default assumption should be that the lifespan of the solenoids follows some unknown distribution and that there is nothing the consumer does or doesn’t do that leads to or prevents failure.

[mlines]

so, you purchased this K-70 new in 2019, and the repair place diagnosed 'Aperture Block Failure'?
That is earlier than I would expect the "Dark Image Syndrome" to rear its ugly head.

Did you run the PF software
Check Camera Shutter Count and Manufacture Date
on an image to determine shutter count and date of manufacture?

I didn't run it before it went away, I didnt know then it could be done, but now it is back.....

Manufacture date: 2017:12:11
Current Shutter count:: 16088

I purchased it "new" in May 2019. It was the shop demonstrator and was sold as "certified new" which is Dealer/Pentax speak for the full warranty applying from date of purchase, I knew it had been a demonstrator.
The bulk of the shutter count is me as I had been doing a lot of astro which consists of hundreds of shutter operations per session. Based on that Manufacture date it is consistent with it doing around a year as the shop model,.

[photogem]

Since there’s been no systematic study of the failures, the default assumption should be that the lifespan of the solenoids follows some unknown distribution and that there is nothing the consumer does or doesn’t do that leads to or prevents failure.

So its your studies? But based on what exactly?

[mtkeller]

So its your studies? But based on what exactly?

My argument is that the conventional wisdom around here about why these solenoids fail is based on nothing but rumor and innuendo. People keep making statements (such as these things never fail in the first x years or that they only fail after prolonged periods of disuse or that they don't fail after y years) that are not backed up with anything. If one were to undertake a study, they would formulate a null hypothesis and look for evidence to disprove it. The null hypothesis would be that there's some distribution of times before failure for these solenoids (likely, one would hypothesize a particular distribution and parameters for the distribution). You'd then collect a random sample of cameras using the solenoid and see at what time the solenoid failed (or if it is still operating without having failed). No one has done that sort of study.

[photogem]

My argument is that the conventional wisdom around here about why these solenoids fail is based on nothing but rumor and innuendo. People keep making statements (such as these things never fail in the first x years or that they only fail after prolonged periods of disuse or that they don't fail after y years) that are not backed up with anything. If one were to undertake a study, they would formulate a null hypothesis and look for evidence to disprove it. The null hypothesis would be that there's some distribution of times before failure for these solenoids (likely, one would hypothesize a particular distribution and parameters for the distribution). You'd then collect a random sample of cameras using the solenoid and see at what time the solenoid failed (or if it is still operating without having failed). No one has done that sort of study.

Ah.... and you had how many solenoids in your hands, measured them, tested them?

[mtkeller]

Ah.... and you had how many solenoids in your hands, measured them, tested them?

I respect and am grateful for all you've done to document how to do these repairs, @photogem. This is going nowhere fast, however, so I'm just going to leave things there.

[reh321]

My argument is that the conventional wisdom around here about why these solenoids fail is based on nothing but rumor and innuendo. People keep making statements (such as these things never fail in the first x years or that they only fail after prolonged periods of disuse or that they don't fail after y years) that are not backed up with anything. If one were to undertake a study, they would formulate a null hypothesis and look for evidence to disprove it. The null hypothesis would be that there's some distribution of times before failure for these solenoids (likely, one would hypothesize a particular distribution and parameters for the distribution). You'd then collect a random sample of cameras using the solenoid and see at what time the solenoid failed (or if it is still operating without having failed). No one has done that sort of study.

This 'discussion' is almost like having photogem play International-style "football" while you play American-style "football".
He is deducing general behavior from behavior of individual cameras - going from individual behavior to group behavior - while you use want to use statistics to get group behavior.
This is really not a discussion of "rumor and innuendo" - individuals are trying to learn from anecdotes, because - honestly - that is all we have.
I have taken statistics at four different Universities - around a dozen courses in all - but no one has ever talked about selecting the 'correct' statistical model, which is more art than science.
Statisticians often use the 'Normal model' for reasons of theory and practicality, but we already have evidence that it would be the wrong selection in this case.
Perhaps the 'Exponential model' would work better with its non-existant tail towards zero and its long tail towards infinity {it's usually used for light bulbs afterall},
but collecting a random study would be hopeless in any case - we have already had many discussions about the bias that comes from owner's reports.

[reh321]

I didn't run it before it went away, I didnt know then it could be done, but now it is back.....

Manufacture date: 2017:12:11
Current Shutter count:: 16088

I purchased it "new" in May 2019. It was the shop demonstrator and was sold as "certified new" which is Dealer/Pentax speak for the full warranty applying from date of purchase, I knew it had been a demonstrator.
The bulk of the shutter count is me as I had been doing a lot of astro which consists of hundreds of shutter operations per session. Based on that Manufacture date it is consistent with it doing around a year as the shop model,.

"Rats". I was hoping that there would be evidence showing that the reports of "Dark Image Syndrome" on the K-70 resulted from the first batch of them, but such is obviously not the case.
Your experience seems more in line with the typical experience of having the K-70 work fine for several years .... and then it doesn't sometimes.
Oh well, from my K-30 I have developed methods of dealing with this problem, and if the K-90 uses firmware debuted in the K-3iii, that might be all I would need for it to be an advance for me in any case.

[iGlad]

I bought my K-70 in 2017 (manufactured 28.6.2017, shutter count now is 5,089) which I mainly used for attending live gigs.it's not had much use especially during covid. I decided to give it a whirl and guess what the aperture problem has occurred. The 2 year warranty ran out in 2019 and I'm sure there was no extended warranty offered at the time.

I am not proficient enough to take it apart and solder so I'm hoping John Pye will be able to repair it. I've sent them an email about 2 weeks ago via the Ricoh/Pentax website and I'm still waiting for a reply. The John Pye Technical repair website has no contact or email details which I find rather odd. John Pye repairing it seems to be my only option as I am not going to buy another new K-70 body and the step to a KP is well out of my price range.

I am tad disgusted with Pentax as this seems to be a recurring fault in K-70's and yet they have done nothing about it. I take it that Ricoh have never addressed the issue with some kind of recall.

Does anyone have an idea on the repair price?