I have used all sorts of combinations with my digital camera. One was an external power pack of alkaline D cells and it lasted forever. Months. and very cost-efficient.
I also have NiMH rechargeables which I slow charge and they have worked fine too.
I use NiMH batteries in my digital camera and can often go an entire weekend, several 100 pictures on a single set. Since I’m usually backpacking, batteries lasting a long time is important, and NiMHs are the only thing that works well. For any serious digital camera use, get the NiMH batteries and a good charger. Two sets of 4 plus the charger will run you about $45.
The only exception to this is mid-winter when I will use lithium batteries since everything else craps out quickly at -20F.
Ftg is largely correct about the discharge curves for alkaline versus NiCd batteries. In fact, the discharge curves for NiCds are quite flat throughout their useful current range, whereas alkalines gradually lose voltage due to the increasing internal resistance as they discharge. This is the reason you should not use NiCd batteries in something like your smoke detector, since the flat discharge curve means they die very quickly so that if the battery dies while you’re out it may be too dead to give you the low-battery beeps. Alkalines can keep the unit beeping for days after it has reached the threshold the low-battery circuit is set for.
Q.E.D.: In low drain devices (e.g. smoke detectors), I agree it is better to use alkalines. Alkalines have much more energy density (and therefore longer life) vs. NiCADs at low current levels.
I wasn’t talking about long life so as much as safety, vis a vis the low-battery warning, but yes, you’re absolutely correct. Additionally, alkalines have a much longer standby time (due to low internal leakage), which makes them ideal for intermittent duty devices, like flashlights. NiCds, on the other had, self-discharge at the rate of about 10% per month or so.
That, and Ni-Cads self-discharge at about 3 to 5 percent or capacity per day.
That was in reply to Crafter_Man.
Shop around for the best NiMH cells because the technology has been improving. 1600mah for AA cells used to be the norm and I’m not able to get 1800mah cells in a drugstore and some are available with as much as 2200-2300mah.
I’m partial to the Rayovac 1 hour charger becuse it runs on 12v and so can be easily run from a cigarette lightere when travelling. It does heat cells and twice I;ve had a cell overheat so much it split the insulator sleeve. I’m sure someone has a fast charger that’s a little better by now.
FWIW my main camera is a Minolta Dimage 7 which is known for being the most ravenous, battery sucking pig in the digicam world. For long location shoots when I can’t use an AC adapter I use an external pack made from a 7.2v 3000mah pack made for RC cars. It gives me more than enough power to completely fill a 1gb microdrive and run a big Metz potato masher flash.
Hmmmm…those are some crappy NiCds you’re using there, Mort. Cite.
Or else I’m quoting old values from the Ni-Cads the radio manufacturers used to deliver with the radios we used. 
That’s entirely possible. As NiCds age, their self-discharge rates increase, and their capacity decreases. I don’t know if NiMH batteries similarly degrade.
Old values from the (back then) new batteries. Sorry. You’d think I’d have learned to be clearer with kind of thing after posting here for so long.
I fly electric radio-controlled airplanes, and I use nicads, nimhs & lithium-ion polymer batteries.
First of all, if aeropl’s charger is a regular trickle-charger, there should be no problem charging nimh cells with it. I charge 8-cell nimh aaa packs with a 55mah wall charger, with no problems. I can fast-charge my nimhs as well, on the same charger that I use for my nicad packs.
Secondly, as far as I know lithium-ion polymer batteries do not self-discharge. They can stay at a set voltage for months. I don’t know if this is different from regular lithium-ion cells, as I’ve never used them. I had the idea that the main advantage of the “polymer” part was safety - li-poly cells don’t explode like li-ions sometimes do - but perhaps resistance to self-discharging is another.
Nimhs do indeed self-discharge rather quickly. I didn’t know it was as fast as 10-15% per day, but I believe it. I’ve had nicads sitting on the bench for 7 months that still had a decent charge left in them, but leave a nimh pack there for a week & it’s time for the charger again.
I have had many nicad packs. I have never once discharged a pack, in any other way than by using it, nor have I “cycled” any. I try not to let them get too hot, and that’s about the extent of my nicad care regimen. All of my nicad packs have lasted a very, very long time, with more uses than I could count. I have never experienced “memory”, though I’ve charged packs many times after partial use. I’ve read a statement written by someone knowledgeable who worked for a company that makes nicads that basically said that nicad memory was basically a myth, or at least nowhere near as common as people seem to think. My own experience would suggest that to be the case, or maybe I’ve just been incredibly lucky with my nicads.
Um. No. I ignored the advice in my digital Fujifilm’s manual about not using lithium batteries, and two days later it was non functional. I played dumb about it when I sent it in to be repaired, but I’m sure that’s what did it in.