K-x problem at 1/125th

Hi

I have a strange problem with my k-x. If I take a shot at precisely 1/125th I get jitter or slight blur, consistently over the whole shot with any lens. I don't get this at any other speed, even right down to, say, 1/10th, so I don't think this is down to operator error. Anyone else have this or heard about it? My own guess is that it may be something to do with the batteries not pumping out enough juice for the electronics. I am using Eneloops but find that I get barely 100 shots out of them before the indicator starts dropping and soon goes red and the latest occurrence of the jitters was at the low end of the batteries. Any other brand of rechargeables worth considering? FWIW, I have installed the latest firmware which was meant to deal with a battery issue of some kind or another, I believe.

There are four normal causes of blur that I can think of:

- inaccurate focus
- insufficient depth of field
- camera movement
- subject movement

If it's none of these, then there is something wrong with the camera and/or lens.

I take it you've tested carefully using tripod and delayed release to eliminate shake, and achieved careful focus on a focus chart so that you know for certain that you're focusing on what you think you're focusing on?

And that you have focus confirmation for every shot that appears unexpectedly unsharp?

Sorry if this is teaching granny to suck eggs, but it's always worth verifying these things.

Do you get any sharp pictures at all at 1/125?

Was the SR ready? If you press to soon while it's getting set to be ready that might cause movement.

It may have something to do with SR turned on if you are using a tripod, It should be turned off when using a tripod.

Have you tried it with SR turned on and then tried again with it off. ??

Not sure about the 1/125 issue. Took me a while to find a picture that had been taken at 1/125 on my Kx (I shoot in Av mode...), but it looks perfectly sharp to me.

I've not been counting how many pictures I get out of a set of Enloops, err... 500-ish shots so far, recharged twice (I think) and had a freebie set initially, so that's maybe 100-200 shots per charge - I do use the LCD a lot (not for LV (yuck), but its still on to show the status screen and to review pictures).

Its well worth having a second set of batteries anyway - you want to look for the highest mAH rating you can find - we use some Sony CycleEnergy ones in a DAB radio which chews-up normal rechargables, they are also rated at 2000 mAH same as the Enloops.

p.s.
You are charging for the full 7 hours? It is possible you have a duff set, they are only rated for about 1000 charges and will suffer from Memory Effects like all rechargables...

Not sure on the shutter speed with blur problem but you should be getting way more than 100 shots from your enloops. i've used them on my k-x for a bit now and reckon i'd probably get about 700 out of a fully charged set.

Try a fresh set of lithiums see if you still have the same problem, if you do then might be a camera fault. i'm off to a zoo later today i'll try a couple of shots at 1/125 see how they come out.

This problem is actually well known, and there has been A LOT of heated discussion over at the dpreview forums. It seems that some K-x show this weird behaviour where images taken between 1/80 and 1/125 can be blurred. To my knowledge, there has not been a final conclusion, but

- the most likely cause was seen by some as a combination of mirror slap and an inability of the SR system to compensate properly at these shutter speeds
- some people had their K-x repaired, and it apparently sorted the problem, even though it wasn't acknowledged by Pentax service what the problem was
- a number of people believe that it has to do with batteries, i.e. their quality and strength; some even thought that it was an issue of the battery contacts and that bending them slightly improved the problem
- It also seems to be relevant to have the latest firmware revision which provides better power management

If you have the time, it might be worth heading over to these forums and check a few of these discussions.

Ok, I give up, Did I say something dumb :

Not that I can see, Clarky

I would point out that this features in pp 128 -130 in the K-x manual and it does state there that SR should be turned off when using a tripod

...and that is exactly what Clarky said...

indeed he did , but Clarky is not using a K-x , and the OP is - so I just quoted from the book for the OP.

I assumed you only posted that to wind me up, mate

Thanks for all your comments, everyone. Yes, er hem, there certainly seems to be some debate about jitter and what they call "mirror slap" on certain other web forums. Hmmn, if you strip out the argy-bargy the fact is that no one has a definitive answer although enough folks seem to have experienced the problem for it not to be imaginary or operator error. I think I will take a lot more care over batteries, perhaps trying something other than my Eneloops, which are pretty well caned by now anyway. If this does not work and the problem starts to intrude, then a quick trip to the repair folks will be the next thing.