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The Nikon F100 Power Page
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Nikon F100

Nikon F100 and Nikon 24mm f/1.4. I'd get it here, and check here, too.

Battery Consumption

The F100 goes through a lot of batteries. It only gets 10 rolls or so on a set of 4-AA alkaline cells. This unfortunately is normal. Alkaline AA cells which test 40% on the MBT-1 tester read flashing dead on the F100.

I don't recommend alkaline cells except for very light users, and if you are a light user you ought to have an N80 instead.

I have never used the MB-15 six cell holder. Everything you read here is using the standard MS-12 4-AA cell holder included with the F100.

When the first electronic cameras like the FE and F3 were introduced in the late 1970s we all got paranoid about being stranded with a dead battery. We were all such idiots. It turns out that those cameras (and today's FM3a) run for years on a set of S76 watch batteries, and those batteries were tiny enough to carry spare set in your wallet. I always did, and never needed them.

With the F100 you often run down the batteries, you have to haul around spare sets of 4-AA cells and holders, and today no one worries about that. We are still idiots.

Using the standard 4-AA holder I typically get:

Ni-Cds (nickle-cadmium): 6 (six) 36 exposure rolls on a charge of 600 mAh cells.

Alkalines: 10 (ten) 36 exposure rolls. Engineers can find the technical data here for alkaline cells.

Ni-MH (nickle-metal hydride) 14-25 rolls on a charge. My 1,450 mAh AA Ni-MH cells powered me through over 26 rolls at a ridiculous 10 degrees F out photographing birds at dawn in New Mexico in January, 2000, without a problem. That same set just gave me 23 rolls in April, 2001. If you're an engineer you can see the technical data here for Ni-MH cells.

Lithium throwaways probably give over 30 rolls per set. I have never tried them, but the rich people who use them love them. If you're an engineer look here for the technical data on lithium AA cells.

F100 Power Consumption Measurements

OFF: 41.5 uA (something has to keep the exposure counter on!)
ON: (meter not on, just sitting there) 41.5 uA (exactly the same as OFF. The OFF position is really just a lock against inadvertent operation)
Meter ON: 250 mA (any time the viewfinder display is lit or the top LCD indicates exposure values)
Shutter Open: 250 mA (during BULB or any other exposure)
DOF preview pressed and held: 315 ma
AF Operating: 550 ma (Similar for all conventional mechanical AF, AF-I and AF-S lenses)
Film advance (without film): 815-900mA while film advance motor is running

The top panel illuminator only draws a negligible 11mA. Use it all you want without fear of running down your batteries.

Using Ni-Cd or Ni-MH cells with mAh (milli-Ampere hour) ratings you can calculate how long the camera will run, in hours, by dividing the cell's mAh rating (often 1,400 mAh) by the current draw (typically 250 mA) to give an answer in hours (typically 5 hours of continuous operation).

You also can consult the engineering data referenced above for estimating how long the camera will run with each type of battery.

These measurements lead to an interesting observation: letting the meter run for just 5 seconds (300mA x 5 seconds) draws MORE power than the actual making of a photo (900mA x 1/2 second), after which the meter shuts off immediately.

Battery Life Suggestions

As shown above, the F100 sucks a great deal of power anytime the meter turns ON even by tapping the shutter button lightly. Then the meter stays on several seconds as set in the custom functions, unless you actually make a photo. If you do fire the shutter the meter shuts off immediately.

Therefore you will get much longer battery life if you avoid tapping the metering button and twiddling with exposure adjustments and just shoot photos immediately.

Of course you and I need to make those adjustments.

Because the camera shuts off immediately after making an exposure, it actually increases battery life to snap a photo than it does to tap the meter on and let it run for however long you have it set to run, typically 4-16 seconds.

If you often sight through the camera, twiddle with AF or metering, and don't take a photo you'll get better battery life setting the metering shut off time in the custom functions to a shorter time. The F100 shuts the metering off right after a picture is made, but the metering stays on as long as you've chosen if you don't make the exposure. This wears down the batteries faster if you've chosen the longer meter-on times like 15 seconds.

Always carry a spare, loaded battery tray in your pocket. Always expect to be changing batteries when you least want to.

If you shoot less than 10 rolls a month you may be better off with throwaway batteries, because the rechargeables start to loose their charge after a month or two. I'd suggest Energizer Lithium AAs. Lithium AAs cost $2 or more for each AA cell (you need 4) and are a little hard to find. I find the Home Depot in the USA is a good source, oddly.

Avoid conventional alkalines, including those with fancy names like "Titanium" designed to sound like Lithium. The high current drain of the F100 is above the current level at which alkaline cells are comfortable. If you use alkalines (the most common AA cell) you'll go nuts with some batteries indicating LOW and then recovering to OK the next day.

Watch it: real Lithiums are hard to find.

If you still insist on shooting alkalines stay with Eveready. Why? Simple: if they leak on you Eveready still guarantees to repair or replace your camera. Even though off-brand alkaline batteries probably last just as long, if they leak on you you're on your own fixing your camera. I had a set of alkalines (you caught me; I threw a third holder in my bag as back-up with alkalines) and the darn cells leaked. Luckily the holder wasn't in the camera, but in any case the holder and cells are with Eveready as of July 2001 being worked on. They are a great bunch of people.

If you shoot more than 20 rolls a month you ought to look into rechargeable systems.

Rechargeable systems need to be used often enough to run the cells all the way down each month. If you don't use the camera enough to run the cells down each month then the cells start to perform poorly due to memory issues and self-discharge. Yes, rechargeables will run down on their own over a month or two.

Having a box full of Lithiums is the easiest way to go, just throwing them away when you kill them and popping in a fresh set each time. Newspaper photographers do this, since the newspaper is paying for the batteries. They also weigh less than any other kind of cell, and do give the longest life of any type, too. Lithiums are the best choice for subzero weather, too. They just cost more for heavy use. Disposables are much handier than fiddling with chargers.

Rechargeable Systems

Here are my suggestions for those who prefer rechargeable battery systems as I do.

Remember that you need at least TWO sets of batteries: one for the camera, and one to keep ready to put in when the first set dies. You'll also need the second set while the first set recharges. I suggest getting a second replacement MS-12 battery holder so you can have a pre-loaded holder allowing you to swap complete sets of batteries fast, instead of having to fiddle with loading the cells in and out of the holders while you're trying to shoot. Remember that you don't get enough warning to have the luxury of changing batteries when you want to. You'll be swapping sets in the middle of your shoots.

You should not try to get cheap and use only one rechargeable pack by recharging it before you use it each time. Even if you do remember to charge it each night and remember to take the pack with you when you leave, it's bad even for Ni-MH batteries to use only a fraction of their total power on each charge cycle. Over time they will lose capacity if you only use a little of their charge each time. The advantage to battery engineers of Ni-MH over Ni-Cd batteries is that Ni-MH can be restored to full capacity with a couple of full discharge-recharge cycles if you've lost capacity due to this effect (called "memory"), but that is no help if you have an important big shoot and discover that your MH-15 pack only gives you as little life as you've been using previously.

You need two sets of batteries. You need two sets of batteries.

There are three kinds of rechargeable AA cells:

Alkaline. These are rare, cheap, and a poor choice. The high current drain of the F100 will elicit poor performance from rechargeable alkalines, just as one gets poor performance from regular alkalines.

Ni-Cd: This obsolete technology works fine and is inexpensive. Ni-Cd is very happy delivering very high current well in excess of the F100's needs. Ni-Cd will only give one third the number of rolls per charge as Ni-MH, however they work just fine.

Ni-MH: This is the best choice. This modern system gives three times the life per charge as Ni-Cd and costs little more. This is what I recommend for heavy users.

Ni-MH also has a memory issue if you don't fully run down the cells before recharging each time. Unlike Ni-Cds, you easily can get the Ni-MH cells back to full capacity after a couple of full discharge-recharge cycles.

My data comes from Sanyo's NI-MH battery engineering data guide. This is a flyer about 30 pages long that is hard to get unless you are a design engineer of equipment that uses batteries. It covers in explicit detail exactly how to design and build charging circuits, as well as show the discharge curves and storage characteristics of all sorts of their Ni-MH cells. This allows electronic engineers to design equipment, and to select the right cells for the right application. To make the long story short, Ni-MH does show the memory effect according to the inside data. You really have to work at it though , going through many shallow charge-recharge cycles.

Ni-MH is like a muscle. Don't lift anything heavy for a while, and you get weak, but don't realize it till you try to haul a heavy load again. Same for these cells, and just like a muscle, the Ni-MH regain their strength with a little exercise.

The reason marketeers try to brush away the memory effect (actually a depression of voltage partially through the discharge cycle that shuts off the Nikon) is because, unlike Ni-Cd, one can fix the memory problem by fully cycling the Ni-MH cells a couple of times.

Also like a muscle, Ni-MH get flabby sitting around for weeks. Ni-MH and any rechargeable cells are for heavy shooters who run the cells down every couple of weeks at the most. If you don't shoot enough to need to recharge more than once a month than you ought to be using alkalines or lithium throw-aways. Ni-MH discharge themselves over the space of a month or two. Ni-MH are OK for constant heavy use as in a cordless drill or cell phone you charge every other day, but awful for a radio that only gets used a couple of times a month. Use them in a camera that isn't used hard and they may always appear to be dead. This is called self discharge. It gets worse as the temperature gets hotter.

I will admit that my Ni-MH do seem to work just fine even if I don't use the camera or my SB-28 (also fitted with Ni-MH) for even two months.

Li-Ion: This is not available in AA size, otherwise, it would be the best rechargeable power source due to it's light weight and ability to run shallow discharge cycles without memory problems. Lithium rechargeables are popular in laptop computers and camcorders, but AA sizes are unavailable. The non-rechargeable Lithium AAs are the best throwaway batteries you can get.

I suggest ignoring the ridiculously expensive Nikon branded battery packs because it will cost you about $1,000 (!) for the whole setup. You can buy your own system for under a hundred dollars.

Here are the details:

Nikon's Expensive System:

Nikon wants you to buy an MB-15 grip, MN-15 Ni-MH battery packs, an MH-15 charger and the MH-17 charger if you also want to be able to recharge in your car.

Here are the numbers (retail/list prices):

MB-15 grip $165/274 (retail/list)
MH-15 charger $270/405
(2) MN-15 battery packs @ $115/172 each or $230/344 total
MH-17 car charger $215/320

Total from Nikon is $880 at retail, or $1,343 at list price.

Ken Rockwell's suggested system:

Here's what I do and suggest instead:

1.) By an MS-12 standard 4-AA replacement battery clip for your F-100. List price (USA) $20. This way you can hot-swap loaded packs while you're shooting instead of fiddling with AA cells out in the field. I use a rubber band around it while floating around in my pocket or camera bag to keep the AA cells from falling out.

2.) Buy a set of 4-AA Ni-MH cells and rapid charger. This link shows a good one.

3.) Buy another set of four AA Ni-MH cells (heck, buy them for all your SB-28s, too while you're at it). Expect to pay $20/set for name brands. These are the best; they are the Sanyo cells rebranded as Kodak last I looked. If you feel lucky and trust blank green unmarked cells you can get them from battery station, also over the Internet, for about $2 US each cell. You want the HR-3U cells with regular button top.

4.) Want to be able to charge in your car? Buy a 12V DC to 120V AC power inverter and just plug the AC charger into it. The smallest inverter will work. Here's one example for $30.

You're all set for $70 US, or a savings of over $800 US even at discount retail. If you want the car option you can get an inverter for $50 US, and of course you can use the inverter for running many other things in your car like your wireless laptop PC, too, to enjoy KenRockwell.com anyplace on earth.

If you prefer the MB-15 grip then just buy a total of 12 AA Ni-MH cells and a spare MS-15 6-cell holder for the MB-15 grip for $30. Instead of the Kodak 4-cell charger go find a 6 cell unit at Radio Shack.

Of course you can skip the spare tray, but don't complain to me when you drop a cell down a manhole cover and have no way to finish your shoot while fiddling with a battery tray.

One Nikon sponsored photographer just announced Nikon's obscenely expensive MH-17 car charger for the ridiculously expensive Nikon packs that sells for a mere $215 to $320. Sure, he's just trying to give you some friendly advice. If you already use those Nikon packs you've already bought the AC powered MH-15 charger, so you can just use a $50 power inverter to run the MH-15 AC charger in your car without needing the $250 Nikon car charger.

Nikon does not mention using 4 Ni-MH AA cells in the F100's manual. Will I go to Hell?

Nikon does not mention rechargeables for use the standard 4-AA holder in the F100 instruction manuals. That is either because they want to sell you their $1,000 (US) solution, or the fact that the F100's battery meter isn't set up for correct operation with the rechargeables.

My Ni-MH have not caused a problem in the 1.5 years I've used them. Again, I think Nikon is trying to scare you, as well as the fact that people do do stupid things and Nikon is trying to save those people from their own stupidity when they use non-Nikon components in their systems. The stupidest thing people do is use non-Nikon lenses. Batteries are smaller issues.

The biggest battery issue is that the battery meter isn't too happy unless you have freshly charged cells. If you are not a heavy user (over 20 rolls/week) you may have to play a little to get the battery meter to read correctly if the cells you put into the camera when one set dies haven't been charge recently, even though they are full. That is the best reason that Nikon would caution about rechargeable batteries.

The only potential for damage is that rechargeable cells can put out far more peak current if they are asked to. If there is a short circuit inside an F100 and if Nikon was negligent in not properly fusing the F100 then it could catch fire, since rechargeable cells can put out almost unlimited current when short circuited. Also if the camera was designed to depend on the limited peak current supply produced by throwaway batteries then there is no such limit from the rechargeables.

I don't worry about this. Even if my F100 burst into a ball of flame, a brand new F100 costs less than the Nikon setup for rechargeable batteries!!!!!!! Maybe you also worry about the Klingerman Virus and the proposed E-mail tax (SB602). Not I.

The Oddball Battery Strength Meter

This indicator is pretty poor. It either says OK (full battery symbol) or LOW (half battery symbol).

If the battery meter reads LOW then the viewfinder display only stays on while your finger is pressing the shutter button. Even though the meter is on and the top display remains on, by blanking the viewfinder display you'll know you have a low battery without having to check the top plate. This of course is very annoying when you do have low batteries.

I get about one half to a full roll when the meter says LOW.

The battery gauge has what engineers call "hysteresis" After it has read LOW it requires a much higher battery voltage to reset the meter to FULL. This keeps the meter from changing its mind on you when the batteries get a chance to rest and reading FULL without you replacing the batteries.

If you use rechargeables the meter may not decide to read FULL even if you insert a set of fully recharged cells if they have sat around a while.

In engineer speak, the F100 meter changes to LOW when the battery voltage drops to 4.6V (1.15V/cell). It then requires a battery voltage of 5.4V (1.35V per cell) in order to reset back to to FULL. It will continue to read FULL until the battery voltage drops to 4.6V again.

Until it is reset to FULL by either a very freshly charged set of rechargeables or a new set of throwaways, it may read LOW even with a perfectly good set of recharged cells. This is because Ni-MH cells that were charged a while ago usually only are at 1.34V/cell. Oh well.

This happens to me often since the second set I keep with the camera was charged usually a month ago when it ran down and I changed sets. I usually shoot 20 rolls a month, so I usually recharge once a month. Remember I'm putting the dead set on the charger, and putting the second set I charged a month ago back into the camera.

To get the F100 meter to reset to FULL, either:

1.) Pop in a new set of alkalines or lithiums to reset the meter, and then drop your Ni-MH back in. The meter will now read FULL and you're ready to go.

or, what I usually do is to

2.) Give the Ni-MH I charged a month ago a quick few minutes of charge on the Kodak charger. This will temporarily boost their voltage enough to reset the battery gauge to FULL, and everything is fine.

Even if you don't reset the meter the camera works fine and will give you about 20 rolls reading LOW the whole time. The only problem is that the viewfinder display keeps shutting off as soon as you take your finger off the shutter, and of course you won't really know when the batteries are really getting low.

If this happens too much it's a hint from God that maybe I ought to shoot more, or just use throwaway batteries.

This meter hysteresis is a very minor reason to blow $1,000 on Nikon's battery packs, but otherwise, just remember that the meter may not reset to OK unless you first pop in a set right off the charger, or a set of alkalines. For all I know, even if you do blow a grand on the Nikon batteries you may still have the same problem!

I am curious to see if my new (June 2001) F100 is any different here.


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