[geezer52]

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.

It would be useful to know which store you were dealing with and what their source of information was. Seems a bit odd that if there was a recall, that a recall was not more widely known about, and that those who had purchased the affected models had not been notified of the potential problems. Seems like a large retailer like Adorama or B&H would certainly be aware of any recall.

[Jim Radcliffe]

It would be useful to know which store you were dealing with and what their source of information was. Seems a bit odd that if there was a recall, that a recall was not more widely known about, and that those who had purchased the affected models had not been notified of the potential problems. Seems like a large retailer like Adorama or B&H would certainly be aware of any recall.

I agreee. B&H is where I bought my K5 and I've not heard of such a recall. I've spent a lot of money with them and they do have their customers in mind. I would also like to know the name of the store you are dealing with. To the best of my knowledge Pentax has not issued a public recall notice either.

[Rin]

dont they mean the recall of the stained cameras?

[greentreee]

It would be useful to know which store you were dealing with and what their source of information was. Seems a bit odd that if there was a recall, that a recall was not more widely known about, and that those who had purchased the affected models had not been notified of the potential problems. Seems like a large retailer like Adorama or B&H would certainly be aware of any recall.

hi,

here's the quote from Henry's in canada...

"The K5 has had problems with the sensor and with a command dial, but a recall was issued in the earlier part of this year to fix these issues. New K5 units are free of these defects."

that's all i know, sorry the slow reply, dial up is what it is.

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Last edited by greentreee; 07-17-2011 at 08:16 AM. Reason: just adding quote marks

[manishved]

Jim,

Did you measure the voltages on both the batteries? Is there any difference?

Manish

[George Lama]

FYI - 201101 is not the battery serial. It's probably the build/mfg date. My K5 batteries both have 201101 on the label.

[jamesm007]

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 possible 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

I think your the type who will really enjoy looking at the service manuals. There are many but only go up to the K20D; but it shows everything inside and gives a good idea how they are made. There is plastic gears that move the mirror and aperture lever arm. Remember something has to move the arm behind your lens to the right spot when taking a pic and that part has wear and tear as well. There is also many places that need grease. It is applied in the area right to the left of the mirror box where the aperture arm control is.

Downloads

The side of a K10/20, type camera. All the spots in yellow have to have grease applied before and some after assembly.



The parts put on, note all plastic gears. I don't worry about the shutter as much as failure else ware. My K10D died at 38,000 clicks and it was not the shutter, it was one of the other moving parts!

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Last edited by jamesm007; 07-17-2011 at 10:26 AM.

[dave216]

dirty contacts on gear (9) seen at pictures 3 and 4 above cause mirror flop issue on k10d, so i think there must be similar mechanism in k5

[rvannatta]

Unfortuantly the situation with mirror flopping on my K5 has esclated rapidly. I first noticed it just a flop or two a month ago. A couple of weeks ago it was really irritating after the battery change as it flopped so much as to interfere with a photo shoot i was doing. Yesterday I had to recharge the battery, and when reinstalled
it pretty much flopped most of the time when ever you turned it on and the camera
was unusable. I let it sit overnight figuring that the edge would drift off the battery
by sitting around, and it did.--- just occasional flops and you could take photos
with it between the occasional flops

[LaurenOE]

Sounds like I should set the battery priority to the grip. That way, I am always charging the grip, as the battery in the camera drains down over time and eventually I charge that one. Or maybe it should be the other way around?

There has got to be a way to take the edge off newly charged batteries if this appears to be the reason behind all the issues.

[philbaum]

Unfortuantly the situation with mirror flopping on my K5 has esclated rapidly. I first noticed it just a flop or two a month ago. A couple of weeks ago it was really irritating after the battery change as it flopped so much as to interfere with a photo shoot i was doing. Yesterday I had to recharge the battery, and when reinstalled
it pretty much flopped most of the time when ever you turned it on and the camera
was unusable. I let it sit overnight figuring that the edge would drift off the battery
by sitting around, and it did.--- just occasional flops and you could take photos
with it between the occasional flops

Sorry to hear that. as someone mentioned above, flipping out the onboard flash and popping it a few times should take the edge off.

[Jim Radcliffe]

Jim,

Did you measure the voltages on both the batteries? Is there any difference?

Manish

No, I did not... every battery I own (3 of them) when fully charged causes the mirror flop. After recharging the half discharged battery from my experiment the camera mirror flopped after the 5th shot was taken.

Don't have a digital voltmeter so no way to meausre voltage but from what I have seen with the batteries.. it's pretty obvious there is a relationship between fully charged batteries and the mirror flops.

[Rin]

what still makes me wonder the most, does this happen eventually with every K5 or is this just something that happens to a batch of users.

[George Lama]

But wouldn't this logic/thought process presume that battery power is allowed into the camera unfettered (sans a voltage regulator of some kind).

If this was the case, then wouldn't using the camera with a power adapter cause mirror flop all the time? Definitely would be an interesting test to perform.

[crunch01]

how long does it take to fully charge battery...
unplug form charger at about 85-90% charge and see what happens..
njust a theory
if it solved prob.. a votltage drain board built from cheap radio shack parts could discharge it bit for when you accidentally let one charge all the way

or a timer in the wall outlet then plug chager in it

this all does sound like a leaking voltage regulator circuit in camer that gets worse... since not every one is repoting this problem I would send in for repair with a note explaing what was found

just an idea