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Forum: Pentax K-30 & K-50
03-23-2017, 06:57 AM
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For your K-50 I suggest getting an AA adapter and using Eneloops Pro, I get super long battery life with them.
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Forum: Pentax K-30 & K-50
02-23-2017, 06:01 AM
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So, I'm reporting back, to bring this thread back to its topic. I repaired my K-50 some weeks ago using a donor part from a 15-year-old Samsung laptop CD drive (see here: K-30 / K-50 Aperture Block Failue - Repair Solution available - Page 21 - PentaxForums.com)
The result after about 900 shots: the camera works perfectly. So I consider the error fixed.
Regarding some other statements in this thread:
I've been using the camera on-and-off, partly only once in a month, then again, intensely. Usually, I've been using Eneloop batteries in the adapter cage. Around the beginning of this year (2017), I began using the D-Li109 battery more often. That's when I first saw the error. This was at around 5500 shots and at around 2 1/2 years after I bought the K-50. After powering up the camera, the first shot would be underexposed, the second would be ok. So, to test this, I switched to burst mode and the underexposed shots had the same Exif info as the correct ones. So I decided my camera had been struck by the problem we're talking about here.
To work around, I switched to Eneloops again and the error went away. But I was concerned that it would eventually show up again even with these Eneloop batteries. So I decided to change the solenoid.
So, I do not think that letting the camera sit on a shelf plays a major part in the development of this problem. But there's clearly a connection to the energy source.
The part I removed form the camera had a green insulator. The part I installed was clear, grey or white (can't remember exactly ;-)), but not green.
The moving part ('horseshoe') of one I removed form the camera was not magnetized at all. It moved smoothly and showed no signs of wear. The force needed to pull it away from the permanent magnet was surprisingly lower than with the part from the laptop.
I didn't investigate this thoroughly, but I think this part works as follows: the permanent magnet holds the moving part/horseshoe in place, while there's a spring connected to the lever inserted into the moving part. The solenoid can either annihilate the permanent magnet's field (counteracting), enabling the spring to pull down the lever, or it can enhance the field to pull the lever back to the resting position. It does this on every shutter release except when using the new eletrical aperture lenses.
So you have three parts in equilibrium: the permanent magnet, the solenoid, the spring. For some reasons, this equilibrium gets disturbed with the green solenoid so that it is no longer able to annihilate the permanent magnet's field. The lever stays in the upper position, because the spring cannot pull it down.
Conjecture: the lever staying up when it shouldn't might cause damage to the aperture block in the long run, which might explain the problems some people here have seen after using the camera a long time after the problem occured. So it might be good to address the problem right away.
Conjecture: the connection to the energy source might point to the solenoid getting out of spec.
Conclusion: While shaving off the horseshoe might put the parts into an equilibrium again, there's a risk that it won't, and also, that the part might degrade further. So, exchanging the solenoid seems to be the way to go, because this makes sure the permanent and electric magnets match each other.
Another conjecture: Putting the poor camera into burst mode and rapidly firing the shutter dozens of times might be doing more harm than good. I'm pretty sure that this means using the camera out of spec and might eventually kill the shutter/aperture motor and/or gears.
If you are stuck somewhere with a hung solenoid, it might be better to try loosening it using the DOF preview, that way, at least the shutter won't be unneccessarily activated.
Finally, regarding this thread: the K-50 is a mighty fine camera, it's light, has good ergonomics, good DR and low-light performance (ISO 3200 is perfectly usable and 6400 is also quite good when using Adobe Lightroom and adding some noise reduction.). As with everything, a complex system might break. Luckily, there's an easy, inexpensive fix.
So I'd like to suggest to some people here, instead of whining and insulting, move on and get over it. Either repair it, get it repaired, or get another camera. But don't make us subject to useless discussions.
'Nuff said ;-)
---------- Post added 02-23-17 at 06:15 AM ----------
I didn't, but I took care to stay away from it's contacts (which is not too difficult). But I didn't take off the top cover, if you do, it might be better to discharge it.
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Forum: Canon, Nikon, Sony, and Other Camera Brands
02-14-2017, 11:44 PM
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Normally, company do what their customers appreciate. Copying what competitors are doing is not necessarily the right strategy.
We should ask ourselves why we ask this kind of question "Canon has done this, how will Ricoh respond?".
It this like when we were 5 years old playing in the sandbox with other little boys of our age and telling our mum "they've got a red tractor, I've got a blue one, the red tractor is stronger, mummy I want the red tractor, mummy i want the red tractor, please, mummy I want the red tractor, mummy please buy me a red red tractor". Truth is often like this, envy. You've got a Pentax cam, you get a Canon , and less than a week after fulfilling your fantasy, life is back to normal shooting again, i.e center point AFS... and for the rest of the time you'll end up shooting with a disposable Canon camera LoL
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Forum: Pentax K-30 & K-50
02-11-2017, 11:27 PM
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As I read all the posts since my last post, all I see here is lots of vague conversations... do not take personally, I am sorry to tell you the truth.
Take my word who is in the repair business for a long time and worked with Japanese teams designing cameras.
The culprit is the new CHINESE MADE plunger solenoid. It is out of voltage specs and it MUST be replaced with a quality Japanese product such as Panasonic, Alps or Mitsumi made.
Filing the part is quite laughable especially when you need to reopen your camera when it fails in a short while.
Mirror box, Shutter and main board has NOTHING to do with that.
Nikon, Canon, Olympus and Minolta has similar mechanism utilizing the same solenoid in a different location due to patent issues.
Nikon D3 and D4 has been upgraded to step motor control due to a different shaped solenoid failure which controls the aperture and it causes the 'Err' message on the early prototypes (which was very common in D2H)
Canon does the aperture in the lens to prevent the same issue.
Replace the part if you can find it and be all set. Pentax is a well engineered brand and has nothing less than the others.
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