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02-16-2010, 07:10 PM   #46
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K-7 , as far as I know, will run on AA`s in the grip, and almost bought it for that reason.
Some other limitations kicked in however.

Cheers, Mike.

02-16-2010, 07:22 PM   #47
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QuoteOriginally posted by UnknownVT Quote
Pentax dSLRs using AA batteries have a long reputation of being very battery fussy - this family trait dates all the way back to the *ist D.
My *ist D was never fussy, what happened is that battery manufacturers entered into a capacity arms race and totally trashed self discharge rates which meant that you had to always ensure cells were hot off the charger to obtain anything like their rated capacity.

I had been using the same 2100mAh cells for years in my Oly E-10 then when the *ist D came along I simply popped the same cells in that and everything was sweet. I should indicate that I generally never use anything but Sanyo NiMH cells, they are an industry reference in the field of NiMH batteries (but they still did create some monsters just before the Eneloops came to market)

I've been using Eneloops in my K-x since day one without problem (but I did purchase it just after the last firmware update).
02-16-2010, 08:41 PM   #48
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QuoteOriginally posted by distudio Quote
My *ist D was never fussy
I stand corrected -
so the *ist D can use just about ANY old AA batteries?

I wonder what changed to make Pentax sDSLRs so notorious for being AA battery fussy?
02-16-2010, 08:54 PM   #49
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QuoteOriginally posted by UnknownVT Quote
I stand corrected -
so the *ist D can use just about ANY old AA batteries?

I wonder what changed to make Pentax sDSLRs so notorious for being AA battery fussy?
The *ist D seems to work with most NiMH, CR-V3 and Lithium AA disposable cells but of course alkali cells or other non-rechargeable aren't recommended.

I think most of the fuss over the years has been more about inferior cells and poor chargers, particularly the ones that charge cells in sets of two or 4 which tends to mask problems with individual cells.

02-16-2010, 09:06 PM   #50
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QuoteOriginally posted by UnknownVT Quote
I wonder what changed to make Pentax sDSLRs so notorious for being AA battery fussy?
I think distudio nailed it: battery manufacturers pursued higher capacity at any cost (preferably lower) and consumers, not knowing any better, bought them. It's only with hindsight (wonderful stuff that - I wish I could get some in advance) that we know that these batteries quickly deteriorate.

The market seems to be correcting, and it's not only the trend to LSD batteries. The industry-wide rush to higher capacities seems to have slowed, and some big manufacturers are introducing lower capacity cells. For example, Energizer first relabeled its notorious 2500 mAh cell as 2450 mAh. That probably didn't sway anyone who knew about the 2500 mAh cell's problems. Now Energizer is trying again with a completely new 2300 mAh cell. Good luck to them. If it's reliable in the long term I'll happily use them. I don't need LSD batteries (in my camera) that can retain their charge for years. I fully intend to discharge them much, much faster than that, and I'd rather have 2300 mAh than the 1900/2000 mAh capacity of LSD cells. I actually have a set in my K-x at the moment and they're going great so far, but it's too early to tell how they'll hold up in the long term.

Some thing with battery chargers. A 15 minute charger sounds great until you realize how quickly it damages your batteries. (Some people might even decide that's OK.) I just wish all the paired cell chargers would disappear.
02-16-2010, 09:27 PM   #51
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QuoteOriginally posted by distudio Quote
I think most of the fuss over the years has been more about inferior cells and poor chargers, particularly the ones that charge cells in sets of two or 4 which tends to mask problems with individual cells.
In which case my K-x was never battery fussy
- like you, I knew to use eneloops (charged with a Maha C-9000) from the start.

Whereas when I first got my K100D I had a shock that 2500mAh no-name NiMH which worked fine in my Canon p&s would barely power up the K100D -
(of course since then I used eneloops -
however I even found the otherwise excellent Kodak Pre-Charged LSD (suspected re-badge of GP ReCyko) did not do as well as eneloops - please see Post #57 in eneloop vs. Kodak Pre-Charged Voltage Maintenance )

I wonder why there are so just many AA battery threads on this forum then -
if it is the batteries (and not the Pentax dSLRs) that are at fault?
(joking... no offense meant)
02-16-2010, 09:41 PM   #52
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QuoteOriginally posted by UnknownVT Quote
Whereas when I first got my K100D I had a shock that 2500mAh no-name NiMH which worked fine in my Canon p&s would barely power up the K100D -
(of course since then I used eneloops -
however I even found the otherwise excellent Kodak Pre-Charged LSD (suspected re-badge of GP ReCyko) did not do as well as eneloops - please see Post #57 in eneloop vs. Kodak Pre-Charged Voltage Maintenance )
What are Flash Amps? Do you actually test batteries by shorting them on a crappy DMM?

If so that's not a good idea and really a poor way to treat batteries or to determine their performance. It's a much better idea to put them across a known load (such as a resistor chosen to emulate an expected load) and watch what happens to the terminal voltage, you can then make a decent assessment of the cells internal resistance under specific load conditions.
02-16-2010, 10:55 PM   #53
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QuoteOriginally posted by distudio Quote
What are Flash Amps? Do you actually test batteries by shorting them on a crappy DMM?

If so that's not a good idea and really a poor way to treat batteries or to determine their performance. It's a much better idea to put them across a known load (such as a resistor chosen to emulate an expected load) and watch what happens to the terminal voltage, you can then make a decent assessment of the cells internal resistance under specific load conditions.
er - that's not very friendly (what have I done to insult you?)
- please read the thread properly.
Using a resistor load is exactly what I did to to determine the internal resistance of the batteries.....

"Flash Amps" is a pretty common practice - it may seem unkind to the battery - but it is not done for long and I do not do this frequently.

In fact Flash Amps is defined and suggested in the Energizer Battery Technical Bulletin (pdf)

Please note the thread is in the battery forum of CPF and there are many reputable battery experts participating in the both that forum and in that thread.

02-16-2010, 11:04 PM   #54
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QuoteOriginally posted by UnknownVT Quote
er - please read the thread properly.
Using a resistor load is exactly what I did to to determine the internal resistance of the batteries.....

"Flash Amps" is a pretty common practice - it may seem unkind to the battery - but it is not done for long and I do not do this frequently.

In fact Flash Amps is defined and suggested in the Energizer Battery Technical Bulletin (pdf)

Please note the thread is in the battery forum of CPF and there are many reputable battery experts participating in the both that forum and in that thread.
Interesting, they quote using a 0.01ohm shunt resistance (which I indecently have at my disposal), that bulletin was from 2005, it probably relates to NiCd chemistry (note it's not specific regarding chemistry). I still doubt it's a good idea to treat NiMH Hybrid type cells this way, a 1 ohm would suffice and would be a far more representative maximum instantaneous load in the case of a DSLR, and this is what I use (I have a small jig with test button set up), but I'm just an electronics engineer.

PS Interestingly I just did a world wide Google search on the term "flash amps" and got a massive 98 hits, no wonder I had never heard of the term in during my experience as an engineer. Sorry if I appeared rude (I missed your comment) but the notion of sticking a basic consumer ammeter across a charged cell sounded ridiculous (and still does).

Last edited by distudio; 02-16-2010 at 11:21 PM. Reason: PS
02-16-2010, 11:21 PM   #55
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QuoteOriginally posted by distudio Quote
Interesting, they quote using a 0.01ohm shunt resistance (which I indecently have at my disposal), that bulletin was from 2005, it probably relates to NiCd chemistry (note it's not specific regarding chemistry). I still doubt it's a good idea to treat NiMH Hybrid type cells this way, a 1 ohm would suffice and would be a far more representative maximum instantaneous load in the case of a DSLR, and this is what I use (I have a small jig with test button set up), but I'm just an electronics engineer.
I would not disagree that "Flash Amps" is unkind to batteries - if done repeatedly or over a longer duration, and should NOT be used for Li-Ion (where it probably is dangerous).

But it is called "Flash" Amps because it is supposed to be done quickly kind of like an instantaneous reading.

0.01 ohm resistors are fairly uncommon (eg: A little less than 2 feet of 14 AWG wire has a resistance of 0.01 Ohms)
so most people just use a DMM directly relying on the meter's own resistance -
it's not a "precise" measurement - but merely a quick way of checking a battery's health.

However it is pretty common practice for NiMH which has been around for many years - without reports of problems, at least to my knowledge
CPF has a thread where some tried to explain Flash Amps

EDIT to ADD -
Flash Amps is also called "Burst rating" for batteries.

Last edited by UnknownVT; 02-17-2010 at 12:01 AM.
02-16-2010, 11:23 PM   #56
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turn off the blue led light on top, turn off the screen on the back when shooting (i just press info twice once i have my stuff setup), and turn off the preview after each shot and set the camera to auto off after 1min and you're batteries last nearly twice as long.

Then i just run two sets of eneloops, one in the charger one in the camera and never have an issue ever. Can shoot about 40 mins of video or 7 days of photos on one set.
02-16-2010, 11:36 PM   #57
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QuoteOriginally posted by OutOfFocus Quote
Perhaps for future cameras (that need a new body design), Pentax could design a camera that accepts either a rechargeable Li-ion or a AA battery pack (which could be filled with Lithium, NiMH, NiZn, or Alkaline).

I wouldn't mind a lot if I had to insert the batteries into a battery holder that I then had to insert into the camera. It might require the camera to be a teensy bit bigger, but that'd be OK. The K-x is a bit on the small side (for me) anyway.

If the voltage difference between the different types of battery packs (Li-ion vs AA) is too much, they could have different electrical contact points.

Then AA-diehards (myself included) would have a wider choice and the Li-ion zealots might leave us in peace.
They've done that already. Granted you have to purchase the Grip to get the ability but the K7 will run on Both Li-ion as well as AA batteries.

QuoteOriginally posted by Marc Sabatella Quote
Whatever. Of all the things that could possibly confuse you about a camera, if you choose to be worried about batteries, then buy a different camera. I still say that's the easy part. Most of us own any number of other devices that take AA's and have had opportunity to think about this before. And if not, a visit to a camera or electronics store will solve that instantly, as will a simple Google search. If some infinitessimally tiny percentage of the population for whatever reason can't do that, OK, fine, I'd agree Pentax should include a pink slip with the camera recommending hybrds and lithiums. It's just not a big deal except to to people who make it one - and to those for whom it's a big deal in a *positive* sense to be able to share batteries and chargers between devices and have assurance they'll still be able to find cells in the future.

So again, if you can't figure out after all this time which AA's to get, don't get a camera that uses them, but please, leave the rest of us alone. If you don't want to help the newbies who haven't figured out how to use Google to get the answer for themselves, fine, no need to say anything. Took more effort to write up your complaints than to simply make the recommendation, though.
Marc, you've gone and gotten yourself into one of these discussions again haven't you??
02-17-2010, 07:55 AM   #58
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The thing is though, all this discussion, all these endless threads and endless analysis of battery brands, chargers, guages not working, notes needed in the manual or on the box to direct customers to the correct power source and/or firmware ...... it could all be avoided if they just used a proper battery.

Wait, wait, sorry we're all intrepid travellers and often find ourselves in mysterious places that sell REALLY good AA lithiums but don't have power plugs.
02-17-2010, 09:16 AM   #59
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At least for the K200 they did use a "proper" battery - there was a pack of lithiums included, which do last very long - but aren't rechargeable.

The manual states that high power rechargeables should be used (2700mAh+) but indeed it would have been nice if there would be a recommendation for low-discharge batteries in the manual.
I would say that both (lithium and low-self-discharge) are readily available so I still think it is an advantage not being restricted to a special kind of OEM battery pack, especially as they will work "out of the box".
02-17-2010, 10:00 AM   #60
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QuoteOriginally posted by El Zoido Quote
At least for the K200 they did use a "proper" battery - there was a pack of lithiums included, which do last very long - but aren't rechargeable.

The manual states that high power rechargeables should be used (2700mAh+) but indeed it would have been nice if there would be a recommendation for low-discharge batteries in the manual.
I would say that both (lithium and low-self-discharge) are readily available so I still think it is an advantage not being restricted to a special kind of OEM battery pack, especially as they will work "out of the box".
Yeah agreed, I think issue number one is that the genral public are still uninformed about "Low self discharge' batteries. That would solve the reliability issue.

You're still carrying 8 batteries instead of two (assumming one carries a spare), they are still a pain to load, easy to mix charged cells with drained cells and you're carrying more weight than you need to ..... but that's another discussion
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