[MrA]

Hi All. Long time since i've posted here, it seems (busy life etc) Hope everyone's well.

My Pentax K-r has started doing something wierd, and before I start talking to Pentax support I thought I'd see if anyone here had any bright ideas as to what's up with it.

With no apparent cause, my K-r now fires the shutter whenever I press anything on it. Flip the power on, it fires. Press the menu button, it fires. Navigate through a menu, it fires on every click. Turn on live view and it fires as though on continuous mode. The one thing I can't make it do is take a photo, because if I half-press the shutter button, it does the continuous-mode click-click-click thing (but never takes a shot).

I was using bulb mode the last time I used it, but I can't find a setting that I might have inadvertently hit that would make it do this.

Anyone got any thoughts? Have I missed something?

[mattt]

If I recall, this sort of thing occurs due to voltage irregularity. If you have updated your firmware recently, make sure the power source selected in the option menu is actually the one you are using. Further to that, it maybe after many cycles your batteries are not functioning correctly and that could be a source of low voltage. I think if you do a search for "mirror flop" and "Low voltage" you'll find several posts.

[bwDraco]

Remove the lens from the camera and examine the aperture lever on the left side inside the mount. It should be moving up and down every time the shutter fires. If it is stuck down, try pushing it up manually.

This is being posted in the general DSLR discussion forum as this relates to both the K-5 and K-r.

I was messing around with the mirror and aperture control mechanisms of my K-r (it's not broken), and I found some interesting behavior which seems to be closely related to the mirror flop issue. Here are the relevant steps:

1. With no lens mounted, start Live View.
2. While the camera is in Live View, remove the battery. The shutter will close but the mirror and aperture lever will remain in the up position.
3. Push and hold the aperture lever in the down position.
4. Reinsert the battery and turn on the camera while holding the aperture lever in the down position. The camera will cycle the mirror and shutter in an attempt to reset the mirror/shutter/aperture mechanism whenever a button or other control is actuated, for as long as the aperture lever is held down. When the status display is shown in manual exposure mode, and a button (such as the Green button) is held down while the aperture lever is held down, the seconds field will read 9999". When you attempt to start Live View, the camera will cycle the mirror and shutter about 20 times before the Live View screen appears, but the Live View feed is blank, and the seconds field will read 9999.
5. When you take your finger off the aperture lever, and the camera is not in Live View, the camera recovers once you actuate any control, and will shoot normally. In Live View, the mirror/shutter/aperture mechanism resets when you do so, but the camera will cease to function properly until you remove and reinsert the battery.

If the mirror is held up while the aperture lever is held down, you'll notice that the camera keeps cycling the shutter (it'll move up and down whenever you actuate a control or do so continuously when in Live View).

I was able to replicate mirror overrun behavior on a camera that is functioning normally by holding the aperture lever in the down position. This experiment proves that the real cause of the mirror flop issue is a jammed aperture control lever.

My camera wasn't damaged when I did this and continues to function normally after the lens was put back on the camera, but I'm not responsible for any damage this procedure may cause to your equipment.

Here's a previous post I've made regarding this issue:

At 2:35 and 2:46 in the video, notice that the aperture control lever at the left side of the mount is not moving when the shutter/mirror cycles. On my K-r, this lever always moves up whenever the mirror goes up. This corresponds to the CRIS replacement of the aperture control unit on a K-5 with this problem; see post #39 of K-5 bug - Shutter going off by itself:

After 2 months a CRIS for this exact problem mine supposedly is shipping back today. They said thet they did the following

REPLACED APERTURE CONTROL UNIT
REPLACED APERTURE CONTROL CONTACT PAD AND BRUSHES

We will see if it is fixed this time....

It appears that the aperture control assembly has failed on your K-r. Try pushing up the aperture control lever in the left side of the lens mount. If this doesn't help, your camera is defective and needs to be repaired or replaced.

--DragonLord

[MrA]

DragonLord had it right - aperture lever was a bit sticky. Fingers crossed, that seems to have sorted it :-)

Thanks.

[wes k]

Glad you've sorted it, my experience falls in line with what mattt says - it happens to me when my battery is on it's last legs, genuine and generic...

[jkomp316]

I frequently have this problem when using the aperture ring on older lenses. Without power cycling the camera It will fix itself when I go back to the A - aperture setting.

I will tape over the electric contacts with masking tape when I use old manual lenses. This also seems to avoid the problem.

[Verdae]

Thank you Dragon Lord, a stuck aperture lever on my k-r was my problem too! Much obliged to all who posted.

[Happidog]

Thank you all for this thread. It would appear mine was updated firmware and my power source was set to 'auto'. Changed it to lithium and Bob's your uncle! Bizarrely I only had the issue when one particular lens was used but it would seem they're all working fine now.

Thanks again from 'a very relieved at not having to fork out a few hundred quid' amateur photographer!

[derek45]

Glad I found this thread.

July 4th, at the park with the kids, ...not the best day to have camera trouble. LOL

Seems to be working fine again.


Thanks to all

[wes k]

Mine still does this every time the battery's low, still have the mirror flop issue also... cant believe I've not thrown this damn camera in a river yet! lol

[ChristianRock]

It seems like some of your cameras are suffering from premature actuation...

I'm glad mine hasn't had that problem. I wonder if a battery that starts going bad and is releasing a much lower voltage, could be causing some of these issues, particularly wes'.

[Aaron28]

cant believe I've not thrown this damn camera in a river yet! lol

hahaha! ya can throw it at me if I can keep it! I really like my K-r!

[wes k]

I really like it too, don't get me wrong, but I've had these issues 3yrs now and they always seem to get worse when I'm photographing something more difficult!
Was shooting some tiger cubs a week or 2 back, hundreds of people to compete for space... had to remove my battery, mess around with the lever, which wasn't even stuck 4/5 times! Add on the mirror flop issue as I was using my Sigma zoomed in, lucky I shoot hi-burst mode as 5/6 shots were coming out overexposed!!!

Luckily I managed to capture a couple of ok shots...

[Aaron28]

nice pic....glad a good one slipped in there......well dang that does sound very frustrating! yeh maybe don't throw it at me!

[timmijo]

This happened to my K-r in 2012, about two months after I purchased it. Nothing solved the problem, so I notified the seller who vouched for its being under warranty. I had it repaired for free. No problem since then.