[stihlmania]

My 1stD, 1stDS and 1stDL are all working with rechargeable CRV-3 batteries and they have never been happier. I switched to rechargeable CRV-3's 2 years ago for all the D's. My 1st DS is used weekly with a Sunpak DX 8R ring flash [auto ttl] for product photos and so far I have 150 shots on the the recently installed camera batteries and the meter on the camera still shows full charge. When the meter shows half charge, around 250 shots, I change the batteries. The date and time need to be re-set every battery change but I can live with that. I do have the Pentax AC adaptor [K-AC10U] but hardly ever use it since I purchased the rechargeable CRV-3's...

[Bob C.]

some good info here about lithium batteries and open & loaded voltages. an interesting point is anything under 1.70 V open circuit is considered discharged


http://data.energizer.com/pdfs/lithiuml91l92_appman.pdf

Thanks for the ref. That's what it says on page 3, which makes it even more of a mystery that the only batteries I have which *don't* show a flashing "depleted" icon in my camera are the used ones, which read around 1.72V open-circuit (and the alkalines, at around 1.55V); the new ones which read around 1.85V OC show "depleted". Of course, that was my original question...

Bottom line, I intend to try the Cr-V3s, which are the Pentax "recommended" type, when they come in. If they don't work, I'll probably kludge up a test circuit to check all of the AA lithiums under load, per Fig 11 on page 11. And at the last, if it still remains a mystery, I might bite the bullet and try Enerloops, since everyone seems to think they're the greatest thing since sliced bread...

---------- Post added 10-18-18 at 10:58 PM ----------

My 1stD, 1stDS and 1stDL are all working with rechargeable CRV-3 batteries and they have never been happier. I switched to rechargeable CRV-3's 2 years ago for all the D's. My 1st DS is used weekly with a Sunpak DX 8R ring flash [auto ttl] for product photos and so far I have 150 shots on the the recently installed camera batteries and the meter on the camera still shows full charge. When the meter shows half charge, around 250 shots, I change the batteries. The date and time need to be re-set every battery change but I can live with that. I do have the Pentax AC adaptor [K-AC10U] but hardly ever use it since I purchased the rechargeable CRV-3's...

That's interesting. I used AA lithiums from my first use back in '05 or '06, and I've gotten about 800-1000 shots per set before the icon dropped below "full". I hardly ever use the internal flash, which probably makes a significant difference. I only got this battery problem after I didn't use the camera for about 2 years (health problems), and when I turned it on there was nothing, not even the flashing "battery depleted" icon. The resulting fire drill is described in my first post.

[leekil]

I may wind up trying them, but I'll wait until I've tried the Cr-V3's I have on order. Based on what I've read over the past couple of days, it does seem that NiMH cells have been improved quite a bit since the ones I found to be essentially useless about 15 years ago.

If you are talking about losing charge when not in use, then that was probably the case when I was used them as well. But I was using them more for 1) not having to buy new batteries when they ran out and 2) for the long life under heavy use. I used them enough that they didn't sit very long and have a noticeably premature depletion.

[Dartmoor Dave]

. . . which makes it even more of a mystery that the only batteries I have which *don't* show a flashing "depleted" icon in my camera are the used ones, which read around 1.72V open-circuit (and the alkalines, at around 1.55V); the new ones which read around 1.85V OC show "depleted".


. . . If they don't work, I'll probably kludge up a test circuit to check all of the AA lithiums under load,

I think you've answered your own question there: the new batteries haven't worked into any load yet, since all you've done is checked the voltage, while the partially used batteries have. If you "wake them up" as I described in my previous post, they'll be able to handle your camera's start-up demands. And really, putting them in something like a flash for thirty seconds is a much simpler experiment than rigging up a test circuit.

[Bob C.]

If you are talking about losing charge when not in use, then that was probably the case when I was used them as well. But I was using them more for 1) not having to buy new batteries when they ran out and 2) for the long life under heavy use. I used them enough that they didn't sit very long and have a noticeably premature depletion.

That's the difference; I only used them maybe 2-3 times a month, and got much better service from either alkalines or lithiums. If I'd been using them daily, for hours, rechargeables woud have been the obvious choice.

---------- Post added 10-19-18 at 07:28 AM ----------

I think you've answered your own question there: the new batteries haven't worked into any load yet, since all you've done is checked the voltage, while the partially used batteries have. If you "wake them up" as I described in my previous post, they'll be able to handle your camera's start-up demands. And really, putting them in something like a flash for thirty seconds is a much simpler experiment than rigging up a test circuit.

While I never had to do any "wake-up" operation before (and I can't imagine why it would be needed), I'll give it a try, first in a high-intensity flashlight and, if that doesn't work, in a flash. The advantage to the test circuit is that I can monitor/measure the current draw, which can't be done in a flash.

[pentasonic49]

When I had my 1stDS, I always used Cr V3's rather than AA's. AA size batteries are so popular, I'm sure you will find some other use for them. I still have a K100D which has never worked with anything other than the Energiser lithium's due to it being sensitive to voltage. The Cr V3's will be lower voltage than the equivalent new lithium AA's which may well suit your camera better.

[Bob C.]

Start-up voltage seems to be exactly the issue. I received the Cr-V3's I ordered today and installed them. The camera powered-up just fine.I checked the open-circuit voltage,and they measured 3.01 and 3.03 volts. That gave me an idea, and I tried Dartmoor Dave's "wake-up" process. I ran all the non-working Energizer lithiums I had (5 sets of 4 each) through Dave's process by installing them in a Sigma flash and running each set through 3 charge/flash cycles. The OC voltage of all 20 cells was around 1.85V prior to the process. Afterward, each set worked fine in the camera, where none of them had before. The OC voltage after the process ran from 1.68V to 1.71V for all the cells. I think this indicates that the *ist-DS (at least mine) is voltage-sensitive, and won't power-up if the total is 7V or more (1.75V/cell). I suspect that Dave's camera has the same issue, and his process only reduces the voltage to something the camera is happy with. As for CeeCee's reference in post 30, I can't explain why new, unused cells with up to 9 years of remaining shelf life should show waht the reference calls "completely discharged" or why such a "dead" cell works fine and shows full charge in the camera. I can only hope that the cells don;t "recover" to greater than 1.75V each... Anyway, it looks like my problem is explained, if not actually "solved", and I have a usable work-around with the Cr-V3's or "tested" AA's. Thanks to all who offered help!

[Dartmoor Dave]

Thanks for the update Bob. It's good to have a technical explanation of what I've (incorrectly) been calling "waking up" the batteries from someone who really knows what he's talking about. A drop in voltage to what the camera will tolerate makes sense to my definitely non-expert thinking.

[BigMackCam]

Start-up voltage seems to be exactly the issue. I received the Cr-V3's I ordered today and installed them. The camera powered-up just fine.I checked the open-circuit voltage,and they measured 3.01 and 3.03 volts. That gave me an idea, and I tried Dartmoor Dave's "wake-up" process. I ran all the non-working Energizer lithiums I had (5 sets of 4 each) through Dave's process by installing them in a Sigma flash and running each set through 3 charge/flash cycles. The OC voltage of all 20 cells was around 1.85V prior to the process. Afterward, each set worked fine in the camera, where none of them had before. The OC voltage after the process ran from 1.68V to 1.71V for all the cells. I think this indicates that the *ist-DS (at least mine) is voltage-sensitive, and won't power-up if the total is 7V or more (1.75V/cell). I suspect that Dave's camera has the same issue, and his process only reduces the voltage to something the camera is happy with. As for CeeCee's reference in post 30, I can't explain why new, unused cells with up to 9 years of remaining shelf life should show waht the reference calls "completely discharged" or why such a "dead" cell works fine and shows full charge in the camera. I can only hope that the cells don;t "recover" to greater than 1.75V each... Anyway, it looks like my problem is explained, if not actually "solved", and I have a usable work-around with the Cr-V3's or "tested" AA's. Thanks to all who offered help!

Thanks for coming back to us with the results of your tests, Bob. This is helpful for all owners of the *ist D-series cameras (myself included - I have a *ist DL and a Samsung GX-1L). I haven't encountered any problems yet, but battery-related issues aren't uncommon with these models, so your findings are potentially very useful.

Glad to know you're up and running again!

[Not a Number]

The service manual indicates using a 6.5V 3A setting to test the viewfinder functions and a 5.68V 3A to test battery full indicator. 4.66V 3A for battery exhausted test. DC of course. I would wager that if you batteries are within these parameters it should function.

[Bob C.]

Thanks for the update Bob. It's good to have a technical explanation of what I've (incorrectly) been calling "waking up" the batteries from someone who really knows what he's talking about. A drop in voltage to what the camera will tolerate makes sense to my definitely non-expert thinking.

As an EE, it just seems logical, and doesn't involve any "waking-up" that I've never seen in *any* batteries, unless you count lead-acid car batteries that are sold with the acid "to be added". And I wouldn't want to try to pass myself off as a camera expert, but thanks. ;-)

---------- Post added 10-20-18 at 09:59 AM ----------

Thanks for coming back to us with the results of your tests, Bob. This is helpful for all owners of the *ist D-series cameras (myself included - I have a *ist DL and a Samsung GX-1L). I haven't encountered any problems yet, but battery-related issues aren't uncommon with these models, so your findings are potentially very useful.

Glad to know you're up and running again!

Glad to be of some help! Since I retired I hardly ever get to use *any* of my electronics knowledge, so this was, in some ways, enjoyable.

---------- Post added 10-20-18 at 10:03 AM ----------

The service manual indicates using a 6.5V 3A setting to test the viewfinder functions and a 5.68V 3A to test battery full indicator. 4.66V 3A for battery exhausted test. DC of course. I would wager that if you batteries are within these parameters it should function.

Thanks; those numbers sound reasonable for what I know of battery internal resistance, although voltage under load can't be directly converted to open-circuit voltage, and I haven't built a test jig for under-load testing (and probably won't, now that I have a "fix"). Just curious: whwer did you find a service manual?

[Not a Number]

You can find the service manual (only) on the pentax-hack.info site or you can buy the complete documents from service-manual.net.

It won't do you much good without the service software, master lenses, jigs and test strip connectors but there is some useful information especially about how to properly disasemble/reassemble the camera.

[Bob C.]

You can find the service manual (only) on the pentax-hack.info site or you can buy the complete documents from service-manual.net.

It won't do you much good without the service software, master lenses, jigs and test strip connectors but there is some useful information especially about how to properly disasemble/reassemble the camera.

Thanks! After I posted I went online and found it. I realize that I can't use it to become a qualified service tech, just as the car and appliance service manuals I have don't allow me to pretend to be a qualified auto mechanic or refrigerator/oven/etc service tech, but as you say it can provide me with enough info to disassemble and reassemble it if needed, at least partially, without making mistakes due to ignorance regarding how the parts fit together, and in what order. If you saw and remember the "disarming the CIA bomb" scene from MASH you'll know the sort of problems I'lm trying to avoid ("But first, cut the *red* wire"). ;-)

[Cee Cee]

Hmmm, I think I have to chime in here, The lithium Ultimate batteries being discussed here are a special case. Normal lithium batteries have a terminal voltage of 3V, this is determined by the materials used, just as carbon batteries and alkaline batteries have a terminal voltage of 1.5V. What they have done here is try to engineer a lithium based battery to have a working voltage similar to alkaline batteries or that can be used to replace alkalines. The higher open circuit voltage for a "rested" battery is a product of the materials used and the way the battery is made. Looking at the discharge curve of the battery (from the earlier reference) we see that the higher terminal voltage reduces in a matter of a few seconds with use. The implication of this is that the battery must have a high internal resistance when in that initial rested state and as the curve flattens the internal resistance must reduce considerably, so the concept of waking the battery up (or activating the chemical reaction to lower the internal resistance) by drawing current from the battery by means of something which doesn't have a micro controller and software to determine battery condition could well be correct.

I think the only way to determine exactly what is happening is to test your particular camera with a bench power supply connected to the battery terminals and check for any OV protection or shut down in your particular case.

[Bob C.]

Hmmm, I think I have to chime in here, The lithium Ultimate batteries being discussed here are a special case. Normal lithium batteries have a terminal voltage of 3V, this is determined by the materials used, just as carbon batteries and alkaline batteries have a terminal voltage of 1.5V. What they have done here is try to engineer a lithium based battery to have a working voltage similar to alkaline batteries or that can be used to replace alkalines. The higher open circuit voltage for a "rested" battery is a product of the materials used and the way the battery is made. Looking at the discharge curve of the battery (from the earlier reference) we see that the higher terminal voltage reduces in a matter of a few seconds with use. The implication of this is that the battery must have a high internal resistance when in that initial rested state and as the curve flattens the internal resistance must reduce considerably, so the concept of waking the battery up (or activating the chemical reaction to lower the internal resistance) by drawing current from the battery by means of something which doesn't have a micro controller and software to determine battery condition could well be correct.

I think the only way to determine exactly what is happening is to test your particular camera with a bench power supply connected to the battery terminals and check for any OV protection or shut down in your particular case.

I was aware that the "standard" voltage for *some* lithium cells is a bit over 3V (coin cells, button cells, etc) and that the manufacturers have produced lithium cells at a bit over half that, but as an EE, rather than a battery chemist, I had no knowledge of *how* it's done or what the differences might be. I did some research this evening, and found a Wiki article (of course!) which describes the various types (23 different ones, actually, from 1.4V to 3.8V) of lithium cells, including their chemistry and nominal voltage. Apparently there are several different types of nominally 1.5V cells, of which the one used by Energizer is Li-FeS2; the article is here:

Lithium battery - Wikipedia.


While I realize the best way to address the problem is as you described, as long as Cr-V3's work without any issues, and lithium AA cells work as I noted previously, I'm content to work with it as-is. Again, thanks to everyone for all the help and suggestions.