[grhazelton]

Hello -

I have a K 5 and second battery grip with which I am generally very happy. It does have a little oddity; with both batteries having a reasonable level of charge, the battery indicator will fairly rapidly show a dropping charge. If I turn the camera off, and then back on full charge is indicated. I have of course the Pentax original battery and three aftermarket Wasabi units. I really can't determine whether this behavior is unique to any particular set of batteries.

Anyone else experienced this?

[jatrax]

I've generally found the battery indicators on all Pentax cameras to be somewhat unreliable. The k-x was perhaps the worst but I've learned to not pay much attention to them. I always carry a spare and when the camera dies I figure the battery needs changing

[grhazelton]

I've also heard about the general inaccuracies of Pentax meters. My K 10 gives very little warning - it also has the battery grip - but it didn't act like the K 5's meter. I wonder whether the Canikon has similar problems??

[jatrax]

I wonder whether the Canikon has similar problems??

No idea, though someone else here might know. I suspect it is more the battery technology than the camera but I'm just guessing on that.

[VisualDarkness]

Same here with all my Pentax. Quite remarkable how they manage to be so consistently inconsistent in that area.

[Alex645]

An electrical engineer (not me) could probably explain this best, but from my experience, this is not unique to Pentax cameras or batteries. Disposable batteries will have a higher voltage and the voltage loss is a fairly slow and steady line on a graph. Rechargeable lithium-ion batteries use higher amperage but less voltage and will keep a more consistent voltage during usage, but will suddenly drop off a cliff. You'll see this with all devices including laptops and cell phones.

Sometimes a change in temperature is enough to take an apparently dead battery to one that has recovered and is charged. The only brand that I've used that seemed to use "smarter batteries" that communicate with the camera were on Sony video camcorders. Bottomline: All batteries die. Bring a spare fully charged one with you at all times.

[VisualDarkness]

Though there are for sure different models and qualities of voltage monitors and I am pretty sure that the ones Pentax uses arent top notch.

[grhazelton]

Thanks for the comments. I shot today - Grandson's third birthday - and the K 5 did its usual thing - I kept on shooting for perhaps thirty minutes with the indicator saying no charge. No problems. Just now I turned on and it said full charge! BTW, I rarely use live view. I guess I'll have to use one battery at a time and see if the phenomenon is battery correlated. And I'll shoot more with my new to me Nikon S2! Manual focus rangefinder, set it yourself shutter and aperture. A favorite of war correspondents back in the day!

[jatrax]

If I understand this correctly the indicator is reading battery voltage which can be used as an indication of power left but is not in fact really power left. As a battery drains the voltage supplied does slowly decrease but it is not linear. In fact by design the ideal battery would provide a constant voltage right up until it dies. No battery I know of quite does that but they try. Now if the indicator is smart enough they could match the tested voltage to a predicted power curve and make a guess on the power remaining. How sophisticated that is I have no idea. And I would assume as batteries age that curve would change. And third party batteries would have a different curve.

So in short the indicator is not very accurate. I just ignore it and swap when the camera dies. Or when the indicator changes to yellow if I'm in the middle of something critical.

[devouges]

The only time I have found the battery indicator reliable is when it says that I cannot take pictures any more..... and I can't take pictures any more.....

[Skodadriver]

I have just put my K-5 battery on charge, when lifting the flash the battery indicator was orange and showed about half a bar. I was a little annoyed as yesterday (about 20 images ago) it showed 2 bars. However, checking the number of images it had taken on one charge, it came to 1383 images!
I don't really care if the battery indicator doesn't seem reliable, the number of images taken on one charge is remarkable. At least I think so. Pentax original battery so a few years old now.