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09-05-2018, 04:02 PM   #1
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K-70 aperture motor question

I am considering upgrading my k50 to a k70 because of the aperture motor failure in the k30 and k50. I repaired my 50, but I dont fully trust it now.

I know the aperture motor in the K-30 was a known issue and was also used in the K-50.


Does anyone know if they re-engineered that part in the K-70 or would I be looking at the same issue down the road? If it is the same part, then I will keep my cash and shoot my K-50 until itnis completely worn out and hope for the best that the ap. motor doesnt fail again.

09-05-2018, 04:20 PM   #2
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According to some that have called & talked to Ricoh/Pentax reps,they supposedly changed it. However, I have heard of some failures from other users, but not from the forums. The only one that I have seen is this post & this post on DPReview. Same user. I haven't seen any other post on this forum or elswhere about it other than some user helping another user that is not on a forum, but then again the K-70 was released in 2016 so it's still kind of relatively new. We might not see much about it. There have also been some issues with K-S1/S2, but less than the K-30/50.
09-05-2018, 05:12 PM   #3
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QuoteOriginally posted by 35wailin Quote
I am considering upgrading my k50 to a k70 because of the aperture motor failure in the k30 and k50. I repaired my 50, but I dont fully trust it now.

I know the aperture motor in the K-30 was a known issue and was also used in the K-50.

Does anyone know if they re-engineered that part in the K-70 or would I be looking at the same issue down the road? If it is the same part, then I will keep my cash and shoot my K-50 until itnis completely worn out and hope for the best that the ap. motor doesnt fail again.
TSM is essentially correct in what he says. There have been a few issues reported with the K-S2, but it is just now reaching the age where you'd expect serious problems to emerge; I've heard 'hear-say' stories of a few issues with the K-70 in Germany. I 'm not a materials scientist - I don't know whether Pentax fully understands this issue, and I do have questions as to whether their supplier could go back to the exact formula that apparently served them well for thirty years.

Incidentally, the issues with these cameras is a solenoid - a version of electromagnet - not a motor per se. There are instructions here how to replace the solenoid. Another alternative, which I plan to follow if the DIS becomes too bad before I get around to purchasing a KP, is to use lenses, such as M42, Pentax-M, or Pentax-FA lenses with aperture ring so you can control the aperture at the lens, because the failure comes in the mechanism that enables aperture to be controlled from the body.

This all matters because I believe the K-70 does use the basic design that the K-30 and K-50 used, a design which apparently goes back to the early days of the KA-mount in the early 1980s (*). Pentax has definitely said that the KP uses the K-7/5/3 design instead, but I don't remember their ever giving a definite answer concerning the K-70 design,


(*) I purchased a Pentax Super Program in 1983, and mostly retired it in 1995, but I still have it and its aperture control still works on the rare occasions when I use it. I purchased a K-30 thirty years later {2013} and as of several months ago it shows Dark Image Syndrome symptoms on the first shot each day - but nothing after that. I believe the two cameras have the same aperture control design, with parts sourced differently.

Last edited by reh321; 09-05-2018 at 05:19 PM.
09-05-2018, 06:06 PM - 1 Like   #4
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Buy the K-70. A damn good camera for the cost. Two people on DP Review are having questions? DP Review? Really? Anyone here on PF have a confirmed aperture block failure with their K-70? Anyone? Bueller? Bueller? My thoughts about the k-70 pretty much match up with this guys review. Although he gives a more glowing review than I would. I do not know this guy. Maybe we'll both be proved wrong sometime down the road. Then again, maybe not. I suggest you search this forum for K-70 pictures so you can see what's possible. When there is this much money involved there is never an easy answer. Bottom line? Have fun with what ever equipment you choose.

PHOTOGRAPHIC CENTRAL: Review: Ricoh's Pentax K-70 - An Outdoorsman's Ideological DSLR (With Press Commentary)


Last edited by DW58; 09-05-2018 at 06:53 PM.
09-05-2018, 08:53 PM - 1 Like   #5
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The K-70 aperture controller is reportedly* similar in design to that in the K-50, K-30, and numerous other flagship and consumer model cameras going back to the mid-1980s. Unlike the K-50 and K-30 there has been no epidemic of wide-spread aperture controller failures. In fact, I am not sure there have been any confirmed reports from users on this site. That does not mean that users have not had problems with poor exposure, only that causes such as user error have been identified.


Steve

* No firm information is available on the subject, the assumption being that consumer models would continue to use the previous design.

Last edited by stevebrot; 10-11-2018 at 10:02 AM. Reason: clarification
09-07-2018, 12:06 AM - 2 Likes   #6
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I will say this, if it were an epidemic issue, it would be all over the internet and not isolated cases. Don't worry about it, get the camera you want.
09-07-2018, 05:56 PM - 1 Like   #7
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QuoteOriginally posted by 35wailin Quote
I am considering upgrading my k50 to a k70 because of the aperture motor failure in the k30 and k50. I repaired my 50, but I dont fully trust it now.

I know the aperture motor in the K-30 was a known issue and was also used in the K-50.


Does anyone know if they re-engineered that part in the K-70 or would I be looking at the same issue down the road? If it is the same part, then I will keep my cash and shoot my K-50 until itnis completely worn out and hope for the best that the ap. motor doesnt fail again.
I've had my K-70 for a year now, shutter count just over 3110 (fingers crossed ) no problems so far!
09-15-2018, 08:21 PM   #8
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hey, the op made me scare......

09-30-2018, 11:50 AM   #9
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I have had my K70 just over a year and a little over 3400 shutter count. Mine just failed and I'm awaiting a response email about the warranty. Still probably isolated cases as I have our seen 1 or 2 others besides mine at this point. I wouldn't hesitate to recommend the camera. Only wish I had better luck out of mine. 😂😂
09-30-2018, 02:17 PM   #10
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QuoteOriginally posted by CodyH Quote
I have had my K70 just over a year and a little over 3400 shutter count. Mine just failed and I'm awaiting a response email about the warranty. Still probably isolated cases as I have our seen 1 or 2 others besides mine at this point. I wouldn't hesitate to recommend the camera. Only wish I had better luck out of mine. ����
How did your K-70 fail?

Edit: Just reviewed @CodyH 's other (virtually identical) post and it claimed aperture block failure. So then the question is whether this was determined by examination of the aperture blades (diagnostic) or some other means.


Steve

Last edited by stevebrot; 09-30-2018 at 02:23 PM.
09-30-2018, 02:32 PM   #11
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QuoteOriginally posted by stevebrot Quote
How did your K-70 fail?

Edit: Just reviewed @CodyH 's post and it indicated aperture block failure. So then the question is whether this was determined by examination of the aperture blades (diagnostic) or some other means.


Steve
Yes aperture block failure of some kind. I've tested 3 lenses on it and set shutter speed to 2 seconds and looking down the lens from the front there is no difference in the aperture blades(they close all the way down) regardless of setting. All pictures are very dark even outside on ISO3200. Sad thing is I'm 15 days out of warranty. Now I'm not a professional or a camera tech, but from everything Ive read, that's what I'm dealing with.
09-30-2018, 03:05 PM - 1 Like   #12
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I would contact RIcoh Imaging US. In the past they have covered the repair out of warranty. You would probably get a better response call the customer service number on the warranty card than using the email contact from the website.

They typically will want you to send the camera in for inspection by Precision before making a decision. The worst that could happen is they say "no" and you are out the cost of shipping. They may say "no" flat out. Either way you don't have too much to lose.
09-30-2018, 06:43 PM   #13
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QuoteOriginally posted by CodyH Quote
Yes aperture block failure of some kind. I've tested 3 lenses on it and set shutter speed to 2 seconds and looking down the lens from the front there is no difference in the aperture blades(they close all the way down) regardless of setting. All pictures are very dark even outside on ISO3200. Sad thing is I'm 15 days out of warranty. Now I'm not a professional or a camera tech, but from everything Ive read, that's what I'm dealing with.
Yes, the full stop-down regardless of setting indicate a fault in aperture control. Whether it is the same sort of fault as with the K-30/K-50 or some other problem is hard to say without a service visit.

QuoteOriginally posted by Not a Number Quote
I would contact RIcoh Imaging US. In the past they have covered the repair out of warranty. You would probably get a better response call the customer service number on the warranty card than using the email contact from the website.

They typically will want you to send the camera in for inspection by Precision before making a decision. The worst that could happen is they say "no" and you are out the cost of shipping. They may say "no" flat out. Either way you don't have too much to lose.
Ricoh Imaging U.S. has been very good about honoring warranty service requests on cameras recently out of warranty. Good luck and let us know the outcome


Steve
09-30-2018, 07:01 PM   #14
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QuoteOriginally posted by CodyH Quote
Yes aperture block failure of some kind. I've tested 3 lenses on it and set shutter speed to 2 seconds and looking down the lens from the front there is no difference in the aperture blades(they close all the way down) regardless of setting. All pictures are very dark even outside on ISO3200. Sad thing is I'm 15 days out of warranty. Now I'm not a professional or a camera tech, but from everything Ive read, that's what I'm dealing with.
I've been using the term "Dark Image Syndrome", because "Syndrome" is used in human medicine to identify a condition which is initially identified by symptoms. I've discovered that when I load one of these dark images, even a JPEG file, into my computer, there really is an image there - but the histogram shows that all the light is crowded into the bottom 1/4-th or so {if camera was calling for around f/5.6} of the histogram. This is 'proof' that the aperture was closing down to f/22 {smallest opening on most of my lenses} even though f/5.6 is shown in the EXIF, but of itself tells nothing about the cause.

added: I hope Pentax is able to help you with this - please do let us know what you hear from them.

Last edited by reh321; 09-30-2018 at 07:39 PM.
10-05-2018, 09:46 AM   #15
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QuoteOriginally posted by CodyH Quote
Yes aperture block failure of some kind. I've tested 3 lenses on it and set shutter speed to 2 seconds and looking down the lens from the front there is no difference in the aperture blades(they close all the way down) regardless of setting. All pictures are very dark even outside on ISO3200. Sad thing is I'm 15 days out of warranty. Now I'm not a professional or a camera tech, but from everything Ive read, that's what I'm dealing with.
Did you have a lens with an aperture ring, so you could set aperture from lens rather than from body, which you could use with the camera??
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