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12-25-2012, 06:31 AM   #46
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I've been measuring voltages..........

I hadn't really tried out AAs yet despite having a cheap Hong Kong adapter, so I thought it was time I tried it out. This was partly because of Zafar's experiences but also because I have yet to find a decent cheap D-Li109 alternative. I've bought 2, one 1100mAh at 5 and one 2000mAh at 9 and both measure more like 4-500mAh and charge up in half the time of the Pentax one which is a bit of a giveaway. So, the AA measurements......

I chose my oldest most used 6 yr old 2100mAh Uniross Hybrios which seemed about the same as my 2yr old Eneloops a couple of years back when I compared them in my K100D, not quite as good if I remember correctly but they were 4yrs old at the time. I think recent Hybrios are made by Sanyo, but these look different so may not have been. They were last charged 2 weeks ago. Straight off the charger they were about 1.45v each. After 2 weeks they were all 1.36v which is typical for all NiMh although low self discharge types would be slightly better than ordinary NiMh at this stage but a lot better after 6 months. I started taking shots in approx 10 minute sessions spread over 4 hrs, with little LCD usage (1 sec review) and using AF on a 35/2.4 on a different subject each shot, no bursts, turning on the display occasionally to check the battery monitor which was set on Auto. I couldn't see any difference by setting it to NiMh by the way. I used the flash once at the end of each session to see if it would kill the camera (it never did). I took the batteries out and measured their voltage on a DVM at the end of each session or if any warnings came up or if the monitor reading changed.


zero shots .........fully charged display........ 1.35v
200 shots ..........half " ........ 1.29v
300 shots ..........zero " ........ 1.24v still working fine.

Now this is where it gets a bit messy as NiMh cells do tend to recover with a short rest.

328 shots.........battery depleted warning.........1.23v (but see later, cleaning affected this reading)

In the light of previous K100D experience I took the batteries out, cleaned the contacts of the batteries and holder with a residue free switch cleaner, and reinserted, spinning each battery (it helps).

328 shots (cleaned) ........ half charged display.......... 1.24v
350 shots..........................zero " .......... 1.23v still working fine
400 shots..........................zero " .......... 1.23v still working fine
450 shots..........................zero " .......... 1.23v still working fine
500 shots..........................zero " .......... 1.23v still working fine

At this point I've had to release myself for full time Xmas festivities. I'll continue another day with the same batteries but I won't repeat this exercise ever, I've no desire to wear my K-30 out. Preliminary conclusions? The meter is useless but it's not easy to get these right with NiMh, they vary too much. Clean contacts are essential, there's so many of them with 4xAAs (10 contacts). I would expect loads more shots before a zero display shows if I were to use freshly charged batteries, but they would carry on and on same as these 2 week old ones have. Bear in mind that technically speaking NiMh are still good at 1.20v and their voltage doesn't really fall off the cliff until about 1.15v so preliminarily I think Pentax are being a bit conservative - we'll see.

Edit update:-
After 24 hr rest, the batteries had all recovered to 1.25v each from 1.23v the day before (the wonders of NiMh)

500 shots..........................half charged display.......... 1.25v
550 shots..........................zero " .......... 1.23v still working fine

There started to be a small difference between battery voltages, so from now on I just measured the total of the 4xAAs

650 shots..........................zero " .......... 4.87v still working fine
700 shots..........................zero " .......... 4.86v still working fine

1hr rest here before measuring so the batteries recovered a bit

760 shots..........................zero " .......... 4.89v still working fine, about 48hrs now since I started
950 shots..........................zero " .......... 4.85v still working fine, nearly 4 days now since I started
1000 shots........................zero " .......... 4.84v still working fine, nearly 4 days now since I started

At this point I thought 'enough's enough'. 1000 shots is enough for anything surely, so I then put the K-30 into playback showing an image and turned power saving off. Every 20 mins approx I tried out Live View for one shot to see if its high current would shut the camera down. It did, but not for another 2 hours!

so, finally:-
1006 shots + further 2 hours of playback --> SHUTDOWN ........... 4.64v

This, I would say is just about optimum shutdown voltage in the K-30 running on AA NiMh rechargeables as their voltage will start to fall quickly below 1.15v and we're almost there (4x1.15v = 4.60v). AAs do vary a lot in their mid-range plateau voltage, and ones with the highest voltage should be chosen to get maximum life. Eneloops are a good choice. There's loads of AA graphs on the candlepower forums if you feel like googling. The K-30 battery meter is useless but the camera's use of AAs isn't but you definitely need clean contacts so as not to waste those precious tens of mV that make all the difference. The length of time the camera is powered up is definitely a factor though, the 0.21A lowest current means you have a maximum of a theoretical 9hrs with 2000mAh batteries, but will obviously be less in practice. Use the power saving timer, it will help a lot.


Last edited by SteveB; 12-29-2012 at 06:51 AM. Reason: more data
12-25-2012, 01:48 PM   #47
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I have little to no knowledge about batteries. I do believe though, that my Ansmann Energy 16 pulsecharges and should be a good charger overall.

I'd say your findings are similar to what I've previously experienced over a number of times. I never took notes since I was shooting at weddings most of the times but generally speaking, I could keep on shooting after re-inserting the batteries for quiet some time. I'd get something like up to a couple of hundred shots and not something like squezzing 5 more exposure of of the batteries.

A particular thing was though, that the K-30 starts to behave weird after "forcing" it to use the same batteries. It starts randomly to make weird noices (never got it solved exactly what could be causing it - did a video of it). Lock-ups when the cam on. Can't tun oit on but after reinserting batteries without any particular pause would enabeit to turn on again and perhaps a single or few more other things.
12-26-2012, 06:46 AM   #48
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QuoteOriginally posted by Zafar Iqbal Quote
I have little to no knowledge about batteries. I do believe though, that my Ansmann Energy 16 pulsecharges and should be a good charger overall.

I'd say your findings are similar to what I've previously experienced over a number of times. I never took notes since I was shooting at weddings most of the times but generally speaking, I could keep on shooting after re-inserting the batteries for quiet some time. I'd get something like up to a couple of hundred shots and not something like squezzing 5 more exposure of of the batteries.

A particular thing was though, that the K-30 starts to behave weird after "forcing" it to use the same batteries. It starts randomly to make weird noices (never got it solved exactly what could be causing it - did a video of it). Lock-ups when the cam on. Can't tun oit on but after reinserting batteries without any particular pause would enabeit to turn on again and perhaps a single or few more other things.
Ansmann make good stuff, and I think that's the charger we use at work, it seems fine.

I haven't seen any lockups so far during this exercise.

I'm now up to 550 shots. The batteries recovered @500 shots from 1.23v to 1.25v after a 24hr rest with 1/2 meter reading. The 500 to 550 shots took the batteries back down to 1.23v each and zero reading and still working fine.

Last edited by SteveB; 12-26-2012 at 06:53 AM.
12-26-2012, 07:23 AM   #49
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Half and zero reading. I have no idea what that means

12-26-2012, 09:24 AM   #50
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QuoteOriginally posted by Zafar Iqbal Quote
Half and zero reading. I have no idea what that means
The battery monitor symbols. There's only 3 states shown. Full, half, and empty. My initial findings would seem to show that full means full, half means 90% or something high anyway, empty means anything between 3/4 full and empty. i.e. it's pretty useless.

I've just taken some K-30 current consumption readings for anyone interested in technicalities. These aren't dead accurate or anything, it's tricky to do for one thing, and just measuring can introduce errors. Anyway here they are FWIW....

Idling (i.e. ready to take a shot), no display, 0.21A constant
Idling, with display 0.28A constant
During AF, saw >0.8A bursts
Taking shot after AF finished, with no display, saw 0.64A, tailing off to idling in a second.
Standby e.g. auto shutdown as expected was essentially zero current.
Live View....0.42A, constant until shutter press then 0.64A, tailing off to 0.42A after a second.

The idling current is much higher than my K100D which was 0.08A. The time the K-30 is just switched on will be a big factor in number of shots achieved, going by these figures.

Last edited by SteveB; 12-28-2012 at 03:41 AM. Reason: more data
12-26-2012, 09:53 AM   #51
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Ah, makes sense now I too have noticed this. I haven't payed attention to when it does it, but the K-30 is eager to show the orange indicator. I recall I had shot 350 shots during the last shot and it was already on orange. I think It might have been on red/empty by the time I reached 500 exposures.

Thanks for elaborating.
12-27-2012, 12:39 PM   #52
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I'm up to 1000 AA shots now, still working. I'm editing my big post above so it's all in one place.

Last edited by SteveB; 12-29-2012 at 03:15 AM. Reason: more data
12-29-2012, 03:07 AM   #53
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I've finished my AA test in post no. 46. AAs rule OK.

12-29-2012, 05:45 AM   #54
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Very nice. A reliable battery indicator is needed. It's completely useless as it is now. I also somehow feel (again, I have no clues about batteries, especially rechargeable) the safety precautions are too narrow.
12-29-2012, 07:02 AM   #55
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QuoteOriginally posted by Zafar Iqbal Quote
Very nice. A reliable battery indicator is needed. It's completely useless as it is now. I also somehow feel (again, I have no clues about batteries, especially rechargeable) the safety precautions are too narrow.
Thanks. Well, the shutdown voltage could be taken a little lower, but not with all rechargeable AAs, they do vary a bit and some won't have much power left under 1.18v, some quite a lot, and there has to be enough power left for the camera to be able to shutdown cleanly without crashing, so I think it's about right but 40mv lower would be OK I reckon assuming the camera can operate with this low a voltage of course, it may not. The variability between battery types also then affects how the designers can use the meter, 5 segments would be much better than the 3 we have. At present, the 3 meter readings correspond to:-

Full(green) = >1.29v
Half(yellow) = 1.25v-1.29v
Empty(red) = <1.25v

What would be better in my experience of many old and new AA NiMh could be:-

Full = >1.26v
Half = 1.21-1.26v
Empty = <1.21v
12-29-2012, 06:15 PM   #56
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Had all the batteries gone though the recharger yesterday and was at an engagement party today.

First set of batteries on body 1 gave me 650 exposures - this is after reinserting them once. Exposure count was probably 620-630 before reinserting the batteries.

Body 2 was at about 800 exposures but I replaced the batteries when the cake was brought out. I didn't want to risk it to die on me in the middle of cake slicing or whatnot.

Both bodies are K-30.
Body 1: Sigma 70-200mm f2.8 non OS version
Body 2: Sigma 17-50mm OS f2.8. Never used the lens OS
I did use few other lenses on both but the exposure amount with those is marginal in comparison.
AF-S and AF-C on both bodies. I relied more heavily on continuous exposure on body 1 (70-200).

Display was always on. Instant preview as well - again, on both cameras.

If I didn't mention it before: I use Sanyo XX 2500mHa batteries.

My battery changer tells me I have 0% juice left on the batteries I took out on my own from body 2.

The depleted once, or at least that's how cam 1 was behaving with them, have 50% according to this simple battery tester :\

Both battery are less than a year old and should have been burned well in by now.
12-29-2012, 09:33 PM   #57
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I just went through a complete cycle of the stock battery for the K30 over a period of two days. Freshly charged, put in the camera, and used for picture taking until the LCD said "battery depleted".

736 shots! (going by the shutter count) This is by far the most I've ever gotten with the stock battery. Usually it lasts only until the high 400's.

The circumstances were thus:

- Over 95% of the pictures were taken with the Sigma 30 1.4 in all of its screwdrive glory (AFS was used the entire time).
- Over 95% of the pictures were taken in an indoors environment.
- I swapped lenses a few times for various purposes, but never for any major length of time (I estimate I took around 30-35 pictures with other lenses, totaling between 10-20 minutes of use).
- Flash was not used for any of the pictures.
- There were 3 or 4 long exposure shots, but every other shot was pretty normal.
- For almost every picture taken with the Sigma, I viewed it on the LCD and peeped its details (I was trying to correct the stupid Sigma's front focus issue).
- There was lots of chimping (I probably deleted 95% of the pictures I took, mostly the test shots), which meant lots of LCD "on" time.

I'm still trying to figure out how this came to be, since every article on the K30 I've read states that the battery should only last until the mid 400's.

Anyways, I did also receive a couple of cheapo Chinese AA adapters in the mail this week that I bought from Ebay. I then went to Walmart and got an 8 pack of Energizer "advanced lithium" AA's.to test out the adapters while the main battery was charging.

I set the K30 to recognize these AA's as lithiums in the menu.

AA Set 1 - In live view, lasted only 2 shots (turned on, battery bar at green, first shot brought the bar down to yellow, next shot brought it down to red) before the "battery depleted" notice came up on the LCD.
AA Set 2 - Using only the OVF, I got a few more shots out of it (I think between 5 and 10). However, as soon as I went to the LCD to check the battery level, the bar went to red, and then going back to the OVF it quickly died after a shot or two.

I don't think the K30 drained the batteries completely. I think the K30 just didn't recognize the batteries because of how little power they put out.

For giggles, I then put in a set of batteries I got from the dollar store (Panasonic "carbon zinc" batteries). Menu was set to "auto" AA. Miraculously, the K30 turned on. I went to live view, and the bar was red. I tried to take a picture, and I heard the mirror flip up, but the camera just froze and the screen went all weird. It kind of freaked me out, but I suspected that something like that would happen so I pulled out the memory card beforehand. The camera wasn't responding to anything until I pulled the Panasonics out (they went straight to the garbage can). I put in the Energizers and turned on the K30 to make sure everything was okay, and the mirror and shutter completed their actions. Everything else was fine.

It seems that good batteries are needed to take proper advantage of the adapters.

This all leads me to the question of whether or not the AA abilities of the K30 are worth it. I had it in mind that I would be using that ability when I was out on a bicycle tour or other adventure, when I've run out of batteries and I can then just go to any gas station to get a new set of batteries to see me through. But this preliminary testing showed that even good batteries (advanced lithiums are good, right?) don't last too long. If I need to stock up on some Eneloops beforehand, why don't I just get a bunch of the stock batteries and make sure they're fully charged beforehand. Even if the stock batteries last until the mid 400's as they're supposed to, it will probably be a wash cost wise vs the Eneloops, and a lot less hassle too.

EDIT: Also, does it make any difference to set in the K30 menu the type of AA's being used?

Last edited by EarlVonTapia; 12-29-2012 at 09:50 PM.
12-30-2012, 02:23 AM   #58
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QuoteOriginally posted by EarlVonTapia Quote

Anyways, I did also receive a couple of cheapo Chinese AA adapters in the mail this week that I bought from Ebay. I then went to Walmart and got an 8 pack of Energizer "advanced lithium" AA's.to test out the adapters while the main battery was charging.

I set the K30 to recognize these AA's as lithiums in the menu.

AA Set 1 - In live view, lasted only 2 shots (turned on, battery bar at green, first shot brought the bar down to yellow, next shot brought it down to red) before the "battery depleted" notice came up on the LCD.
AA Set 2 - Using only the OVF, I got a few more shots out of it (I think between 5 and 10). However, as soon as I went to the LCD to check the battery level, the bar went to red, and then going back to the OVF it quickly died after a shot or two.

I don't think the K30 drained the batteries completely. I think the K30 just didn't recognize the batteries because of how little power they put out.
Something very strange is happening there. Energizer lithium non-rechargeables should be the very best batteries you can ever put in your K-30, much better than even the Pentax lithium rechargeable, they should have loads of 'power'. The only catch is that you can't recharge them, but they (should) make a perfect backup set. I have a set that I've always kept in my camera bag that I bought (about 6) for K100D backup. I never ever needed them, so they are still around after about 5yrs. They have an expiry date on them of 2021. I put them in my K-30 which was set to Auto detect AAs and I got a full reading on the battery meter. I took 10 shots in live view, the meter still showed full and I've now put them back in my bag.

Either your batteries or adapter aren't good (are the batteries loose for instance, or are the batteries genuine?) or possibly it's the latest firmware fixed something. If you are on 1.01, see my firmware thread, there's another 1.01 now it seems.
12-30-2012, 01:31 PM   #59
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QuoteOriginally posted by SteveB Quote
Something very strange is happening there. Energizer lithium non-rechargeables should be the very best batteries you can ever put in your K-30, much better than even the Pentax lithium rechargeable, they should have loads of 'power'. The only catch is that you can't recharge them, but they (should) make a perfect backup set. I have a set that I've always kept in my camera bag that I bought (about 6) for K100D backup. I never ever needed them, so they are still around after about 5yrs. They have an expiry date on them of 2021. I put them in my K-30 which was set to Auto detect AAs and I got a full reading on the battery meter. I took 10 shots in live view, the meter still showed full and I've now put them back in my bag.

Either your batteries or adapter aren't good (are the batteries loose for instance, or are the batteries genuine?) or possibly it's the latest firmware fixed something. If you are on 1.01, see my firmware thread, there's another 1.01 now it seems.
Thanks for the reply Steve. I think something fishy is going on. I'll do some more testing today.

For reference, here are the exact same batteries I purchased (except I purchased an 8 pack):

Energizer AA Advanced Lithium Battery 4-Pack (EA91BP4) : Digital Batteries - Future Shop

The battery adapters I bought are cheap Chinese versions of the D BH109. They were advertised as working for the K-R, but I've read that the K-R uses the same adapter as the K30, so that was why I went for them. They were $5 each, and an extra $5 for shipping, vs getting a single official adapter for $40 new locally. The price was right.

Also, I am still on the original firmware. I've been too lazy to upgrade. Could that have something to do with it?
12-30-2012, 03:22 PM   #60
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QuoteOriginally posted by EarlVonTapia Quote
Thanks for the reply Steve. I think something fishy is going on. I'll do some more testing today.

For reference, here are the exact same batteries I purchased (except I purchased an 8 pack):

Energizer AA Advanced Lithium Battery 4-Pack (EA91BP4) : Digital Batteries - Future Shop

The battery adapters I bought are cheap Chinese versions of the D BH109. They were advertised as working for the K-R, but I've read that the K-R uses the same adapter as the K30, so that was why I went for them. They were $5 each, and an extra $5 for shipping, vs getting a single official adapter for $40 new locally. The price was right.

Also, I am still on the original firmware. I've been too lazy to upgrade. Could that have something to do with it?

Those batteries look totally different to my definitely genuine Energizer lithiums but mine are 5yrs old so I looked on the Energizer site and the batteries and packaging look the same, but there's quite a few complaints about batteries being dead as bought, strange as they used to have an excellent reputation. If you have a voltmeter, good new ones measure about 1.80v from memory. My ones read 1.75v.

My adapter is a super cheapy from the far east, forget where exactly but it's fine. As long as the terminals have a decent tension there's not much to go wrong if the AAs fit OK.

As for firmware, it could make a difference. Do you remember the K-x fiasco? AAs weren't lasting 50 shots on a lot of cameras so they brought out a firmware update to fix it.
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