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07-15-2011, 06:11 PM   #31
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awesome, thanks for the testing! It does sound like too much voltage is the culprit. I hope it doesn't get worse over time.

I'm pretty sure battery voltage increases with temperature so heat can still be an additional factor. If I can get my camera to flop consistently, I'd like to try comparing a fully changed battery, a fully charged battery that's been stored in the fridge, and a half charged battery.

07-15-2011, 06:31 PM   #32
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Just carry a can of Refrigerant Spray and try cooling the battery down when it goes crazy with a liberal dosing. That'll tell you if its battery heat/voltage related - or camera based.

I'd say try chilling the K-5 - but I dont think spraying the outside of a WR body will do much good... but I could be wrong.
Of course, carrying a small pocket multimeter to check the actual battery voltage at the time would be handy as well

Whats really needed... is someone to strap a 10 channel logic probe to it when it is/isn't happening... couple channels on the battery, couple on the shutter, couple on the power-circuit specifically to the shutter, and one to the trigger mechanism on the shutter circuit...

The downside is of course; that this is now doing very much Pentax's work for them, and it'll no doubt void your warranty in the process!

Last edited by adr1an; 07-15-2011 at 06:56 PM.
07-15-2011, 06:53 PM   #33
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My mirror began flipping after I put the battery in that I had charged overnight. Has not done it since.....
07-15-2011, 09:52 PM   #34
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QuoteOriginally posted by LaurenOE Quote
I wonder how many flashes it would take for the batteries to settle down. A few flash cycles could quicken the battery drain. I suppose you could up the LCD brightness or do some other power intensive things on the camera if you suspect over charged/topped off batteries.
For those that have them, it might be worth trying a fully charged non-OEM battery if you encounter mirror flopping problems. My Pearstone is rated at 1700mah, and the Pentax battery is 2800 mah. The peak voltage is going to drop off quicker with a lower power battery than the full power Pentax one.

07-15-2011, 10:43 PM   #35
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There is no doubt some real room for better testing by Ricoh before they release their first Pentax camera, whenever that is.
With the pressure on all Mfgs. to get a new product out the door and on the shelf and the huge combination of variables that a camera maybe subjected to once in the hands of shooters, I am amazed that there are not many more problems even more serious than what we see.

It is not like they make the same model over and over, just improving a little at a time and having few new bugs to search out. Every model seems to be a radical change in many components, which complicates the job of QC tremendously. We see this in autos, where recalls are common..as common as model changes. Still, over all, it amazes me there are not more problems than we see now.

Throw in the fact that your camera (or most any other) is full of parts from the lowest bidder and it is even more amazing........Seriously, I don't think that these modern cameras are intended to last like a film camera, and are not even in the same ballpark due to the highly complicated design and intricate processes they perform. I just want to get from one model to the next without a major failure.....maybe that is asking too much? I hope not.

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07-15-2011, 11:28 PM   #36
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QuoteOriginally posted by Docrwm Quote
Makes me wonder if the non-OEM batteries or OEM's charged on a non-OEM charger are causing the same problems?
My batteries and the charger are OEM.
07-15-2011, 11:56 PM   #37
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The OP's experiment makes interesting reading but while it seems to point at a battery/voltage problem with his camera in my case the course for the mirror flutter appears to be a different one.

I purchased my K5 late in Feb. this year. I run 2 original PENTAX batteries together with an original PENTAX grip.

The Cam worked faultlessly up until I traveled to Cambodia some 6 weeks ago. The temperature in Cambodia this time of the year is around the 38-40C and 100% humidity. The mirror flutter and malfunctioning buttons of my K5 was constant. The batteries were not fully charges as I had traveled to Cambodia from Shanghai where I had spent 4 says, used the camera quite frequently in Temps of about 25-28C without any problems but could not charge the batteries prior to my departure to Cambodia.

Back in Melbourne I decided not to hand in the cam at CRK for repair because I had another trip booked to Chicago, New York and San Francisco in early July. (In fact I am writing this post from San Fran)

In Chicago the temp was around the 25-28C and the camera was in use 4 days with fully charged batteries without any hickups. I traveled on to New York with used batteries. In New York though the temp last week was some 35-38C and the K5 was malfunctioning with frequent mirror flutter triggered by various button presses. The screen also started to go blank when turning the cam to portrait position and stayed blank until activating the on/off switch.

Today I am in San Francisco 15th July, the temp is around the 14C mark and my K5 is working faultlessly!

So to me at least it indicates that the problems are temperature related. I have been in the unique position to have traveled through some extreme climate/temperature locations within a short time and pretty consistently the K5 works when it is cool but mucks up when it is hot.

Greetings
07-16-2011, 01:52 AM   #38
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well, i got this issue but not with k-5 but with my old k10d with more than 80k shutter count after shooting in a extreme hot day. (avoiding to use k-5 in such conditions).
so i had decided to determine the problem and fix if possible. The problem was in mirror drive mechanism, cleaning contacts from grease helped.
Regarding battery charge, it seems that with fully charged battery mirror drive motor turns bit faster.
sorry for my bad english

07-16-2011, 07:45 AM   #39
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Jim, have you tried to contact Pentax with your hypothesis regarding the "mirror flop" problem?

Seems like there is some unwanted conduction going on that can be induced by either heat or higher than normal voltage (if both causes trigger the same failure spot).
07-16-2011, 10:24 AM   #40
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QuoteOriginally posted by Class A Quote
Jim, have you tried to contact Pentax with your hypothesis regarding the "mirror flop" problem?

Seems like there is some unwanted conduction going on that can be induced by either heat or higher than normal voltage (if both causes trigger the same failure spot).
Yes, I sent them an email this morning. No response yet.. but then, it is the weekend.

I'm more concerned that there might be a component in the camera circuitry that is degrading in some way as I never had the problem until recently (5 months useage). I am now less inclined to believe this is heat related as I have been able to force the malfunction even when the camera is at normal room temperature (74 degrees).

By the way, I charged the battery that was half drained for my original test and it also caused the mirror flops. Ran that test this morning.
07-16-2011, 03:01 PM   #41
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QuoteOriginally posted by Schraubstock Quote
...I purchased my K5 late in Feb. this year. I run 2 original PENTAX batteries together with an original PENTAX grip.

............
So to me at least it indicates that the problems are temperature related. I have been in the unique position to have traveled through some extreme climate/temperature locations within a short time and pretty consistently the K5 works when it is cool but mucks up when it is hot.

Greetings
QuoteOriginally posted by Jim Radcliffe Quote
Yes, I sent them an email this morning. No response yet.. but then, it is the weekend.

I'm more concerned that there might be a component in the camera circuitry that is degrading in some way as I never had the problem until recently (5 months useage). I am now less inclined to believe this is heat related as I have been able to force the malfunction even when the camera is at normal room temperature (74 degrees).
.
Heat not only affects batteries, but it can affect the friction coefficient between any two sliding surfaces and it also affects the lubricating qualities of grease - to the extent that it is used.

Force (of friction) = Coefficient (of friction) X Load (force pushing the two surfaces together)

Really simple linear equation, the problem is the Coefficient can vary a lot. As two surfaces wear each other smooth, the coefficent can vary. I'm not sure how a mirror mechanism is designed, but if its required to move at up to 5 frames per second, its got to be pretty easy thing to operate (and quick). If they depend on a frictional component to keep the mirror in place against its spring, then that restraint mechanism (i.e. kept in place by a frictional force) can change in its effectiveness due to vary minute wear in the parts. These parts (plastic or metal) may not be worn out by any visual inspection, they just won't have the frictional resistance they had when new.

A funny story to lighten the topic:

Where i used to work as a mech. engr, a friend of mine was an electrical engineer (who didn't know much about friction ). His wife had talked him into painting their living room. As he placed his ladder in the living room to do the painting, she inserted cardboard between the bottom edges of the ladder and the waxed hardwood floors to prevent damage to the floor. As he ascended his ladder towards the cathedral ceiling (paintbrush in hand), there was a slight transfer of weight towards the wall, the load was reduced at the lower ladder edges, reducing the frictional restraint force, and the ladder started sliding away from the wall on its cardboard "sled". He tried to step off the ladder as it was going down which resulted in his leg hitting a bannister and fracturing. Other than walking around in a leg cast for a month or two, he survived in good shape. His wife no longer asks him to do work around the house, which he seems to appreciate.

We depend on friction all the time, e.g. your car won't stop in any practical period of time without friction from one's brakes. Its posssible that some cameras have a reduced friction problem due to wearing of parts. Because of the potential high rate of mirror movement (up to 5 frames a sec), that K5 mirror mechanism is going to wear surfaces together (thereby reducing friction between its parts) at a higher rate than say the K10 or K20.

It would be interesting to see if those reporting mirror flopping are using continuous rates of shooting more than those who are shooting singles. It could be that Pentax K5 is not up to a lot of continuous shooting with this particular mirror design.

I think Pentax probably bought their mirror mechanism from a third party, but i don't know that as a fact. This is a lot of conjecture on my part, not being willing to disassemble my K5

Last edited by philbaum; 07-16-2011 at 03:15 PM.
07-16-2011, 05:10 PM   #42
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QuoteOriginally posted by philbaum Quote
Heat not only affects batteries, but it can affect the friction coefficient between any two sliding surfaces and it also affects the lubricating qualities of grease - to the extent that it is used. Force (of friction) = Coefficient (of friction) X Load (force pushing the two surfaces together)
I am fully aware of the law of friction. Before my cam started to misbehave it had little use and I had not used the machine gun setting up to this point. So if your theory holds true than I hate to think what will happen after 2 or three years of use. I think it simply is an electronic component malfunctioning which would explain why the mirror flutter and other problems can be triggered by a number of unrelated button presses.

Greetings
07-16-2011, 05:44 PM   #43
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QuoteOriginally posted by Docrwm Quote
Makes me wonder if the non-OEM batteries or OEM's charged on a non-OEM charger are causing the same problems?
Nope, I have 4 OEM batteries and two OEM chargers. So far CRIS said that "top control board" needs to be replaced, but the part is on order from Japan or something. I use all of these batteries on my K-7 and it is still working.
07-16-2011, 08:54 PM   #44
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Grip and AA batteries

QuoteOriginally posted by philbaum Quote
I haven't had the mirror flop problem yet, but i've had my K5 for 4 months and this conversation has got my interest.

So i tested my batteries, both 1 OEM and 1 non-OEM and the results are in this post:

https://www.pentaxforums.com/forums/1579642-post159.html

Duh, the testing of those 2 batteries showed that the charger determines the final battery voltage, as it was identical after charging in both the 2 different batteries, e.g. 8.41 volts.

So i think you're right, it would be interesting to test some batteries of any make from a car or house charger to see if the voltage is different than the 8.41 volts I got from my charger. If anyone else has a digital voltmeter other than me, please test your batteries and tell us the final voltage and whether you were using the Pentax charger or a different make altogether.

For several though, it sounds like the problem is not showing up till 4 months later - perhaps there is a wear component to this problem. I wonder how many photographers are using the burst mode who have encountered this problem. Perhaps the burst mode is causing premature wear. Just a question.
This has also sparked my interest. I bought an OEM grip for my K-5. My eventual plans were to ditch the priority battery and load up the grip with AA's. Six AA's at 1.2 volts each equals 7.4 volts. That is a full volt under the fully charged priority battery. I am wondering if I would ever experience the mirror flops? Even if I don't, should I send my camera in for service prior to the warranty expiring if Pentax has a fix? Will Pentax actually have the corrected replacement part or would they just be replacing it with another part that has the inherent flaw? I don't expect any answers at this point - I just have questions.
07-17-2011, 06:21 AM   #45
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i don't own a K5 yet, but ordered one last week, then found this post.

i then emailed the store to ask them about the problems (since the order is on hold), and was told that the production models from earlier this year had the issues mentioned in this thread and were recalled, and the problems were fixed.

forgive me if this has been posted, i just thought i'd mention it.
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