Originally Posted by daved163
I used the supplied Panasonic alkalines and managed to get about 35 shots out of them. This concerned me greatly given that the manual claimed 300 shots! I had a rumage and dug out some old NiMhs: given that I'm returning to photography after many years away the best I could manage was 1850mAH. I charged a set of GP 1800s and a set of Sanyo 1850s (standard, not hybrid) overnight and stuck the GPs in first. I was horrified when a few minutes later the low battery signal came on and barely 5 shots later the camera started "ticking" (one of the motors hunting). I turned it off and ... it wouldn't -it just kept ticking.
In retrospect it seems the batteries couldn't supply enough jiuce for the firmware to complete the AF/AE cycle it was engaged in and the poor thing just sat there going round in motorised circles. I opened & closed the battery door several times but the problem persisted and eventually the camera just played dead. I measured the battery voltages with a DMM and they were right up there at 1.25 volts. No problem with the batteries, then, so I assumed the worst and was almost ready to send it back. I put new alkalines in and the camera worked again, but I was still a bit worried.
Anyway, I pulled the Sanyo batteries (not Eneloops, remember) from the charger before they'd finished cooking and popped those in. I spent an hour and a half trying to exhaust those batteries, to no avail. The manual states NiMh should be good for 400 shots or so - I gave up after 500, when the low battery signal came on, and to cap it all, a 10 minute rest saw the signal back to off again and no further sign of it coming back on after a further 50 shots. (You've no idea how tiring it is continually firing a camera for an hour and a half!)
This got me to thinking, especially in view of comments made about Sanyo Eneloops in another thread (including by me) and comments made on DPR about batteries - some of which are highly pertinent. As you know batteries are rated by their capacity in mAh. This is an indication of how long they will last given that they are suitable, performance-wise, in the first place for the application in hand, NOT how well they will perform per se. This is where we're going wrong in asserting that Eneloops or (my own statement in that other thread) hybrid technology is the salient feature. This is untrue.
What is important is the "cold-cranking current" (the phrase comes from lead-acid technology) which is a measure of the short-term current the battery can supply from "cold" (we can read it as peak or instantaneous current, although it's not quite the same thing) and has to do with the battery's internal resistance (specific chemistry). Unfortunately this is a parameter that NiMh battery manufacturers don't state and it's interesting to note that the HS10 manual advises warming the batteries in an effort to get them to work! (My dad used to put his old cycle lamp batteries on the boiler overnight, so it's a proven, if temporary, fix.)
So, I've proved that Eneloops aren't essential, nor is hybrid technolgy (but it is useful because ordinary NiMhs lose their charge over a period of days whereas hybrids don't). I'd now be confident taking the HS10 out for a day with my old 1850mAH batteries, freshly charged. Unless someone can dig out defacto specs which include a cold-cranking figure (or whatever the NiMh equivalent term is). And in the meantime if anyone has a scare like I did, with the camera seeming to die despite having apparently fully charged batteries - change them for ones HS10 users have found to be OK, even if they aren't hybrids.
It seems that the Cameras "in-rush" current are rather high - meaning that the batteries internal resistance should be low ! Otherwise the Cam wont perform correctly !
And the colder a battery is, the higher is the internal resistance.
A high internal resistance means that the battery can't deliver all the power when needed - ie. "the hole in the water hose is too small to deliver as much water as needed !!"
So a list of brand/types of batteries with a low internal resistance is something we wish for - is it not ?
And no - Have'nt got the Cam yet - but will hopefully within the next two months.