[rawr]

Lithium batteries are supposed to be very good at maintaining their (operating) voltage - so I am a bit concerned with your report.

NiMH probably would be worse - as most of them start at a nominal 1.2V as opposed to nearly 1.7V each of primary Lithium AA's.

I think you may be worrying too much about the battery issue.

Although it is a different camera, I've had my K200D for a year, shot thousands of photos, and have only used about 3 sets of lithiums. The two sets of eneloops I bought a year ago have never been used in my K200D. And the lithiums I am using in the K200D at the moment are cheapo non-Energizers I found at the local hardware store for about AUD $8 for a set of 4....

Just for reference, the Pentax AA battery image count rating for the K200D are:
- 1100/550 shots without/with 50% flash shots using lithium,
- 1100/640 w 2500mAh NiMh, and
- 200/80 with alkaline.

For the Km/K2000 it is:
- 1650/1000 with lithium,
- 640/420 with high-charge 2700mAh Nimh, and
- 360/260 with alkaline

For the K-x it is:
- 1900/1100 with lithium,
- 640/420 with lower-charge 1900mAh Nimh, and
- 230/130 with alkaline

which indicates some potential improvements in energy efficiency in the K-x, at least using lithiums in standard photography. The NiMh ratings though are harder to compare due to the different mAh figures Pentax used for each camera, but the K-x does seem to be an improvement over the Km in NiMh.

So there is room for optimism here.

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Last edited by rawr; 10-27-2009 at 04:02 PM.

[UnknownVT]

Just for reference, the Pentax AA battery image count rating for the K200D are:
- 1100/550 shots without/with 50% flash shots using lithium,
- 1100/640 w 2500mAh NiMh, and
- 200/80 with alkaline.

For the K-x it is:
- 1900/1100 with lithium,
- 640/420 with lower-charge 1900mAh Nimh, and
- 230/130 with alkaline

which indicates some potential improvements in energy efficiency in the K-x, at least using lithiums in standard photography. The NiMh ratings though are harder to compare due to the different mAh figures Pentax used for each camera, but the K-x does seem to be an improvement over the Km in NiMh.

So there is room for optimism here.

Thank you for the words of optimism -

However I think you may have the specs of the K200D misquoted - according to the downloaded manual for the K200D

The figures for 2500mAh NiMH were 700/400 -
Pentax do tend to be conservative in these battery estimates/specs.

But you are right it is encouraging - there is definitely improvement -
I have noted this in AA powered Pentax dSLRs since the K100D.

However what I was addressing was specifically the problem that blu3ness had when using HDR on the Kx with lithium AAs - if he was having low battery signals with lithiums - it is possible that NiMH would not be better - that is what I was saying.

Can you see any reason why NiMH would be better?

Of course since Pentax dSLRs using AAs now can set the battery type - perhaps NiMH might not be so prone to low battery signal - if Pentax have done the battery profile correctly - especially if eneloops are used.

[rawr]

However I think you may have the specs of the K200D misquoted - according to the downloaded manual for the K200D

The figures for 2500mAh NiMH were 700/400 -

Ooops. Of course you are correct. Sorry. I don't know where my numbers came from... Those numbers are far more reasonable.

And I can't see any reason for NiMh to exceed lithium performance under the circumstances you describe. But I don't know anything about battery technology, to be honest. So I will shut up about the subject from now on.

[UnknownVT]

And I can't see any reason for NiMh to exceed lithium performance under the circumstances you describe. But I don't know anything about battery technology, to be honest. So I will shut up about the subject from now on.

Neah, don't be so hard on yourself.

You were absolutely right to point out the encouraging incremental improvements on battery life in the Pentax dSLRs using AAs.

I shoot a lot when I use my K100D - and eneloops were definitely the way to go for me - I am getting over 1,000 shots per charge (mostly without flash) and that is with weeks between usage.

We had long threads about battery issues for the K100D, K200D - mostly the problems were solved when people used lithiums (expensive) or eneloops (charged properly).

That is why I was so concerned about blu3ness's reported problems when using HDR on the Kx with lithium AAs.

ref:

K200D Battery Meter Problem

k100d battery recommendation (see links in Post #62)

K200D Batteries

K100D excessive battery usage.

Problem with Ni-MH rechargable batteries in K200D/K-M

Batteries just ran out K200D

K200d and battery problem?

K100D - "Low-Battery" Problem

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Last edited by UnknownVT; 10-27-2009 at 05:51 PM. Reason: re-did links

[blu3ness]

I didn't have a problem with lithium per se, my lithium batteries are still showing green and good. I'm not sure if anyone can duplicate what I experienced that time. I never had the problem again, I'll try to use lithium AAs and shoot some more HDR to see if I get similar warnings about battery. :P

[Eruditass]

There are some more reports of NiMH battery problems in this thread coming up:

http://forums.dpreview.com/forums/read.asp?forum=1036&message=33511780

But also some finally saying they don't have problems there as well. So please help out and post your results with NiMH, particularly with LiveView.

[mcjm78]

Initially mine got similar problem as everyone else on the NIMH batts. I used the Varta 2100mAH which was charged properly in charger that does individual charging circuit.

Then I tried my Sanyo Eneeloop, and its all good again. I did tried to force the battery type to NIMH, waited a minite before putting new batt, and waited a few second before cold start.

Maybe those procedures actually helped? I'm happy now since my batt is now green so far with the last 50 shots. Some were done with LV and quite a bit of reviewing too.

[Eruditass]

Thanks for the observations, let us know how it continues to go! Some people in the DPR thread are "giving up" on the K-x.

[Eruditass]

To help identify whether this is a certain batch of K-x that are effected:

Where did you get your camera from? Where was it made and can you give us the first 4 or 5 digits of the serial number

Two that are having problems:
Dino G: #34346xx Circuit city
Allan Brown: #34340xx Henrys show
#34339xx Henrys in Newmarket ON

bodies made in the Philippines

[ChrisJ]

The secret is to buy a charger that charges each cell individually, most chargers charge batteries in pairs, this works fine if batteries are matched, but they rarely are, one gets fully charged which inhibits the other and the battery pack is only as strong as it's weakest cell.

This is the one I bought a few years ago for my DS and is still in regular use, you can see the separate batteries charging and some, even of the same type, often take longer than others. When it's finished ALL the batteries are fully charged.

Fast Smart Charger, for AA & AAA NiMH, LCD display on eBay (end time 24-Nov-09 20:09:35 GMT)

Usual disclaimer, just a happy customer.

Chris

[Eruditass]

What also happens is it over-charges the fully charged cells, which heats them up and makes them worse.

A charger with independent charging circuits is quite nice, and most of them probably are smart cutoff (-dv, 0dv, temp, etc) chargers which you need in the least.

[dapharmer]

Posted this in the Pentax K-x flickr group. ::

With the batteries the cam came with (energizer lithiums... not even advanced or ultimates) i took about 1100 snaps with varying settings and flash use. I was unable to get ultralast 2000mah nimhs to work but was able to get a set of duracell 2650mahs and a set of targus 2300mahs working. With the duracell I had taken about 500-600 shots before it started to go yellow, many being long exposure.

I had a second run of 500-600 pics (most long exposure) + 2 videos + in camera processing before battery depletion on the duracells. If that kind of performance holds up then thats the only battery brand i'll need. like 8-9$ for a 4 pack and can charge them in a hr 1/2 on a decent smart charger. cant beat it.

[ChrisJ]

The secret is to buy a charger that charges each cell individually, most chargers charge batteries in pairs, this works fine if batteries are matched, but they rarely are, one gets fully charged which inhibits the other and the battery pack is only as strong as it's weakest cell.

This is the one I bought a few years ago for my DS and is still in regular use, you can see the separate batteries charging and some, even of the same type, often take longer than others. When it's finished ALL the batteries are fully charged.

Fast Smart Charger, for AA & AAA NiMH, LCD display on eBay (end time 24-Nov-09 20:09:35 GMT)

Usual disclaimer, just a happy customer.

Chris

[marathoncamera]

I purchased a K-x and the "recommended accessory" Pearstone batteries and charger. With these batteries properly charged, I can get the camera to sometimes come on and take a few pictures before "battery depleted". Another older set of Energizer NiMHs seem to work properly.

A set of alkalines seems to work, however, the manual does not recommend using them.

I have a La Crosse charger and Eneloops on the way.

This is my first Pentax. I must say this is not making a good first impression. I have never seen any strange battery related behavior in any other digital camera I have owned.

[jerrymouse]

470 so far and still on full (sanyo eneloop). Some LV use. Too bad my LCD died, so I have to end this battery test