Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-18-2013, 11:15 PM   #1
Senior Member




Join Date: Jan 2013
Location: Reading, PA
Photos: Gallery | Albums
Posts: 234
Mirror "flops" and on viewfinder...

you can see the image "jump up" a little bit when it does this. It really seems like the mirror is in slow motion. Even when the shutter is at high speeds it does this clearly identifiable flops in like slow motion. This is with the kit non WR 18-55mm

I got some manual glass in the way of some takumar's and it doesn't do this with them. It only occurs with the kit lens and it won't go away unless I take out the lens from the body and put it again. When doing this it will be fix for a couple of shutter clicks and then back again. I saw somewhere something about checking if it does it in any apperture and it really does.

Anybody has had a problem like this before?

BTW

If I take the lens off and shoot with no lens, it doesn't happen either.


Last edited by BigJPR; 06-18-2013 at 11:18 PM. Reason: Added the BTW
06-20-2013, 09:35 PM   #2
Senior Member




Join Date: Jan 2013
Location: Reading, PA
Photos: Gallery | Albums
Posts: 234
Original Poster
Sorry for the double post, but anybody???
06-21-2013, 04:04 AM   #3
Veteran Member




Join Date: May 2012
Posts: 698
Probably you have a sticky diaphragm lever on that lens. I had something similar happen with an old 28mm K manual lens - the lever offers too much resistance and seems to disrupt the proper operation of the mirror lift mechanism, which is linked to it.
Maybe dried out lubrication or something bent out of shape.

The aperture only makes a difference (I think) with a manual lens, because at full open aperture the diaphragm is not actuated at all. However for some reason the full auto lenses (without aperture ring) always very briefly stop down the lens fully before taking the shot. I don;t know why that is done but it means that the mechanism will always offer some resistance even if the aperture is fully open.
06-21-2013, 08:29 AM   #4
Senior Member




Join Date: Jan 2013
Location: Reading, PA
Photos: Gallery | Albums
Posts: 234
Original Poster
Lister6250 that kinda makes sense to me. Is this lever that opens and closes the aperture blades? I checked and then I see that the actual piston type thing on the body is the one that is kind of stucked and then starts to do that double flopping thing because when you press the shutter you can see in there the little pins going up and down but the piston itself that drives the the mirror does not go up and down so the mirror trey flops. Maybe lubbing of some sort? any ideas .

I was trying to take some pictures of the actual thing and point out what it is so you can have a better idea of what actually is happening, thank you guys

06-21-2013, 09:08 AM   #5
Senior Member




Join Date: Jan 2013
Location: Reading, PA
Photos: Gallery | Albums
Posts: 234
Original Poster

I really hope you guys can see it here... it looked brighter in the phone! lol

Basicaly I show with my finger the little lever (it's that where the diaphram from the lens connects?) and it's action normally. Then I hold it with my finger and that's the flopping/fluttering action I get when I mount my only auto lens I own.

I usually will mount it knowing that it's not stucked and I get 1 picture ok and then it get's stucked and will flutter/flop. This makes the AF system to be inacurrate and changes the metering to a usually too slow for the situation speed.

When I mount any of my takumar manual lenses of course this don't happen. I got to try to get a hold of another auto lens somehow to see if it's the lens of the actual lever on the body.

Any sugguestions welcome. I love my manual lenses but every now and again I get lazy and want my AF damn it!!!! lol
06-23-2013, 09:49 AM   #6
Veteran Member




Join Date: May 2012
Posts: 698
BigJPR,
from what I see there is nothing wrong with the camera. It is more likely the lens that is the problem. When you leave it alone it works fine When you put your finger on that lever you are doing exactly what a faulty lens would do - you are putting much more resistance on it than it is meant to handle. You cannot expect it to work when you are physically blocking the lever from doing its job.

The diaphragm lever on the lens is meant to offer very little resistance and the strength of the actuator in the camera is designed accordingly. If the diaphragm lever is too hard or you put your finger on the lever it simply does not have the strength to move it and things go wrong.

I strongly suggest you do not use that lens as it may eventually cause permanent damage to the camera. More importantly do not stick your finger in the mechanisms of the camera - that is precisely the way to actually cause it to become faulty if it isn't already.

Best thing is to borrow another auto lens and try it out - I'm almost sure it will work fine. You may also want to try your auto lens on someone else's camera - though if they knew what was wrong with it they probably wouldn't want that.
06-23-2013, 03:40 PM   #7
Senior Member




Join Date: Jan 2013
Location: Reading, PA
Photos: Gallery | Albums
Posts: 234
Original Poster
Ok... so probably time to sell a couple of them manuals... stay with the 135mm 3.5 tak or the 50mm 1.4 tak and maybe buy a 18-55wr used or maybe something with more range like something in the 17-70 or so... well gives me an excuse i guess. lol

btw... i know i know... keep the finger out... but I didn't know of another way to show you what is going on... is there anything I could do with the lens? I bought the kit on February... I got to check it out...
06-25-2013, 10:50 AM   #8
Veteran Member




Join Date: May 2012
Posts: 698
QuoteOriginally posted by BigJPR Quote
... is there anything I could do with the lens? I bought the kit on February... I got to check it out...
Assuming the lens is indeed faulty (I' quite sure but not 100% certain) it would probably need to be dismantled and serviced but that would probably cost more than the lens itself. You could try some home made repair. I tried that with my old K lens but cannot say I succeeded.

Do however check with a borrowed lens before concluding that the lens is faulty - you wouldn't want to buy a new lens only to find that it also does not work and you need to repair the camera.

I do also have an 18-55 DA L - it was the kit lens with my K-r but I hardly ever used it. I've just had a look at it and the lever does appear to have a significantly stronger spring resistance than all the other auto lenses I have, be they Pentax, Sigma or Tamron but it still works properly on the k-50 (I tried like a dozen shots just to see how it goes). It is a springy sort of resistance, not friction so presumably it is by design - but why it should be so I cannot guess.

As for getting a new lens I found the 18-135 WR to be very nice. I as originally somewhat apprehensive as I had seen some rather bad reviews of it and I bought it purely for its weather resistance - sort of to use only in extreme weather situations. However I was very pleasantly surprised that none of the ills described in the reviews seemed to materialise. I ended up using this lens whenever I would be taking only one lens with me, substituting the Tamron 18-250 which used to serve that purpose. It has of course less reach than the Tamron but to my eyes seems to produce a somewhat cleaner image quality.

06-25-2013, 11:12 AM   #9
Veteran Member
mrNewt's Avatar

Join Date: Nov 2011
Location: ON, RH
Posts: 2,170
Try the lever from the lens... do you feel like is something holding it down? Or does it move freely and effortlessly?
Try it selecting different apertures as well.

If the lens is faulty is a perfect time to "poke it around" if you are interested in trying to fix lenses.
You could learn something new and maybe even fix the lens...
06-26-2013, 08:04 PM   #10
Senior Member




Join Date: Jan 2013
Location: Reading, PA
Photos: Gallery | Albums
Posts: 234
Original Poster
Hey guys, for some odd ball reason it's kinda fix for now. I did the whole go to every apperture and see what happens like lister6520 said and it did it once at 5.0 then I unmounted the lens and with the finger unstucked the lever and mounted the lens and continued my testing from that apperture. I took 10 pictures at each apperture with a constantly fast shutter and then 10 more with what I consider a slower shutter speed of about 1/4 sec. Nothing. 400 and something worthless exposures in total... more or less.

I had left the lens out since I discovered it was the reason and my manual were behaving correctly. Maybe it needed to rest! =) I don't know what it was, don't care what it was as long as it keeps on behaving good.

Thanks lister6520 and mrNewt for the help! and yeah Newt, I was salivating at the proposition of tinkering with something I never tinkered before... ohh well.

Last edited by BigJPR; 06-26-2013 at 08:05 PM. Reason: added total number of exposures on the testing.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k-30, k-50, kit, lens, mirror, motion, pentax k30, pentax k50, shutter
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Don't say Pentax "Q" in French ... "Q" = "cul" = "A--" Jean Poitiers Pentax Q 52 11-10-2013 06:25 AM
Mirror Flops on K-5II ? yusuf Pentax K-5 2 01-13-2013 01:46 AM
"Hanging mirror" on my 67 - who will help me out? Rense Pentax Medium Format 11 10-31-2012 05:48 PM
K5 mirror "stuck up" or "flop"? jpzk Pentax K-5 6 09-09-2011 07:20 PM
Pentax "A" lens and "F" 1.7X converter on K10d yyyzzz Pentax SLR Lens Discussion 4 07-09-2009 05:04 AM



All times are GMT -7. The time now is 11:12 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top