Did you use rechargeable NiMH batteries or Lithium batteries?

Thanks Algi

I found one interesting link and trick: http://forums.dpreview.com/forums/read.asp?forum=1036&message=33709815

"To solve my problem I put on a Manuall lens, so you get the "Enter focal lenght" screen. After that the camera finds the NiHM batteries every time and I have been happily shooting 400 pictures, 4 minutes of video and alot alot of chimping. And the batteries are still showing full."

I haven't any manual lenses and I can't try this trick, but interesting anyway. Maybe one reason for K-x battery problem is still the firmware and I wonder why Pentax cannot solve the problem. Last firmware update was on last december (2009).

One advice, test that your K-x really works with your rechargable batteries. Discharge batteris and charge them at least one time before using them.

I have difficulties with my K-x and NiMH batteries and now I bought new Sanyo Eneloops (2000 mAh) (not Sony as I wrote earlier), see link

My K-x seems now to be working, but I've only taken ten photos with Eneloop and I don't know how long my K-x works with Eneloops.

If it's possible take Lithium batteries as a backup.

Now is the Eneloop batteries charged by Sony's own charger (a total charge time 14 h) and the cells should be full.

I put Eneloops in the camera and the battery indicator is now green. After a few more picture taken with flash and also Liveview experiment the battery indicator is still green.

We'll see how long it takes until indicator goes to orange.

I don't start take more picture to test batteries, but I guess that on Cristmas I'll take couple on ten pictures and then I can see if K-x works or not with Eneloops

I updated the discharge curve (missing ReCyko start voltage):



I will come back after Christmas, and tell what happened.

And if Eneloops dosen't work as they should, I have package of new Ultra Energizer Lithium batteries in my camera back.

Merry Cristmas to all

Now I have disharged GP ReCyko, Tronic 2500 mAh and Sony Eneloop batteries with La Crosse RS-900 intelligent charger using 500 mA discharge current (maximun with four batteries). Curves are not perfect, because I have to write voltages down manually, but anyway here are results:




In my knowled at least ReCykos and Eneloops should work fine, if electronics are designed properly and tested to work with NiMH batteries.

I'll put Eneloops to Sony's charger now and to morrow (on Saturday) I can try K-x with charged Eneloop batteries. Thumbs up.

Does someone know what is K-x's current consuption (xx mA) when power is switched ON + LCD on?

I made short descharge test with GP ReCyko NiMH batteries and here are results:

Battery tests with La Crosse RS-900 intelligent Charger
Discharge current 500 mA

Voltage after . . . . . . 30min . 60min . 2h30min . 3h
La Crosse . . . . . . . . 1,14V . 1,13V . 1,11V . 1,10V
Fluke 97 multimeter . 1,26V . 1,25V . 1,24V . 1,22V

La Crosse's value was fron display (when discharged with 500mA
Fluke's value was measured from battery's terminals (when discharged with 500mA)

So, In my knowledge there aren't any problems with GP ReCyko in generally, but with K-x the situation might be different.


I got new Sony Eneloop batteries on Thursday and tried them. They seems not work better than ReCyko, but then I put Eneloops to charger and after 3h I tried again. I switch on the camera and battery indicator was green, but after couple of shots the indicator went orange. Not very promising.

On weekend I'm going to do same test with Eneloops and La Crosse as I did with ReCyko to see how Eneloops work under 500mA discharge.


Does anyone know what is K-x's low battery voltage limit with NiMH (limit when the camera shuts down)?

BW.
I wrote to Pentax Support to UK and they gave short answer to my ReCyko problem:
"Please try out the following batteries: Sanyo Eneloop. They are said to be the best for the DSRL's.
With kind regards,
Pawel Jedrzejczak
Pentax Digital Camera Support Team"

Now I have tested ReCykos again and they dosen't work with my K-x.

I tested these cell also with external load and voltages were (current about 330 mA): 1,272 V, 1,287 V, 1,269V and 1,267V.

I'm going to order Sony Eneloops and try with them. And for backups I try to find Lithium batteries. ReCykos I put to my flash. Let's see how Eneloops work.

Unfortunately I have to say that Pentax has done quite an unprofessional work with K-x power circuits. I have been working over 20 year on mobilephone R&D and this kind of problems are like beginners work.

One more commment.

On Pentax forum (US I belive) link

was

full Green lasts for about 1/3 (33%) usage (~400 shots)-
half Orange first shows when there is still about 2/3 (66%) capacity left (~800 shots left or lasts for ~600 shots) -
empty Red shows when there is about 1/6 (16.7%) capacity left (~200 shots)

And then total shots were 1200 taken with Sony Eneloops batteries.


Do you have shots counts with Lithium batteries?

BW. With inbox Lithium-batteries I took about 270 pictures including short video (1 min) and I used LCD to view images.