Were's the battery power indicator??

[Cait]

Just got the 580EXII in the mail the other day, and the first thing that I've come across is that I cannot find anything in the manual or on the LCD screen that remotely resembles an indicator for the battery level. How does one know when their battery is about to go kaput?

[brian.austin]

Originally Posted by Cait

How does one know when their battery is about to go kaput?

Note how long it takes between recharges/flash cycles. I test periodically on my 580EX (not the II). If it doesn't cycle fast enough for me, I swap battery sets.

It still amazes me how long the batteries last in my flash. I rarely have to get into the second set during a shoot. And I've never gone into the backup alkalines I carry.

[Julio]

Mine also last long between cycles

[Ed Shapiro]

Except of the old (seldom used- probablu not in current production) non-sealed lead acid batteries which had built in hydrometers to measure the PH of the sulphuric acid contained in the cells, there is really no way to indicate how much energy storage is an a given battery as its power is being drawn. As the others have mentioned, longer recycling times indicate that the battery is loosing voltage and should be changed at that point to avoid flash failure while you in in the middle of a shoot such as a wedding. As a battery ages after many charge/discharge cycles its storage capacity will diminish and will finally need replacement.

Various types of batteries have different "habits" in the way they discharge. Some will diminish gradually and others will experience an abrupt fall off in voltage when their duty cycle is over. That means that even testing a battery under load with a battery tester will not necessarily tell you how many flashes are left.

Some batteries need to be fully discharged before they are recharged, otherwise the will develop a bad "memory" and will hold charges for lesser durations and cycles of usage, It is best to check with you flash units manual to find out the proper charging procedures which will give you more flashes per charge and extend all over battery life. If the flash unit's instructions do not contain this data, check with the manufacturer orthe distributer. It is also wise, if possible, to contact the battery manufacturer to really zero on data such as ampere/hours, recharging rates (in milliamps) and recommended charging periods.

I hope this helps. Ed

[Eero Makela]

My Nikon SB800 does not have a battery meter either so my guess is that for flashes it is normal to not have one. I use 5 NiMH 2500mAH batteries and they always last in the range of 250+ or more

My manual states if it takes longer then 10 seconds to recycle replace.

I usually go on manual and set it to full power and hit test and time it from there to get an idea how long they will last.

[brian.austin]

Originally Posted by Ed Shapiro

Except of the old (seldom used- probablu not in current production) non-sealed lead acid batteries which had built in hydrometers to measure the PH of the sulphuric acid contained in the cells, there is really no way to indicate how much energy storage is an a given battery as its power is being drawn. As the others have mentioned, longer recycling times indicate that the battery is loosing voltage and should be changed at that point to avoid flash failure while you in in the middle of a shoot such as a wedding. As a battery ages after many charge/discharge cycles its storage capacity will diminish and will finally need replacement.

Various types of batteries have different "habits" in the way they discharge. Some will diminish gradually and others will experience an abrupt fall off in voltage when their duty cycle is over. That means that even testing a battery under load with a battery tester will not necessarily tell you how many flashes are left.

Some batteries need to be fully discharged before they are recharged, otherwise the will develop a bad "memory" and will hold charges for lesser durations and cycles of usage, It is best to check with you flash units manual to find out the proper charging procedures which will give you more flashes per charge and extend all over battery life. If the flash unit's instructions do not contain this data, check with the manufacturer orthe distributer. It is also wise, if possible, to contact the battery manufacturer to really zero on data such as ampere/hours, recharging rates (in milliamps) and recommended charging periods.

I hope this helps. Ed

The Canon Speedlites use AA batteries. Charging the flash unit itself is not necessary.

State of charge (SOC) measurements are usually based on voltage discharge and predicted charge life. The battery indicator estimates battery life based on what its baseline is for full charge and what the battery is pushing out at that moment. Since most batteries of a certain type drop in voltage at approximately the same rates, it's fairly accurate. And most electronics today are designed to take a certain range of input voltages and regulate the voltage to what it needs internally. So a drop in voltage doesn't affect operating performance except in fast discharges like charging a flash's capacitors.

Interesting article on SOC measurement techniques at Battery State of Charge Determination

I've noticed newer electronics are including selectors for Alkaline/NiMH vs Lithium-Ion batteries. This is due to the discharge characteristics of the voltage changes. If your electronics asks what type of batteries you're using, make sure it's accurate or you won't really have a good indication of your current battery power.

[Ed Shapiro]

Hi Brian- Great article- thanks for posting the link! This has to be space age battery technology- I love it. For all practical purposes this is the part of the article that pertains to this low-tech photographer (me):

Note that the SOC reference is normally the rated capacity of a cell, that is a new cell. It is not the fully charged capacity of the cell when it was last charged (i.e. the current charge-discharge cycle). This is because the cell capacity gradually reduces as the cell ages and it is also affected by temperature and discharge rate. For example, toward the end of the cell's life its actual capacity will be approaching only 80% of its rated capacity and in this case, even if the cell were fully charged, its SOC would only be 80%. This difference is important if the user is depending on the SOC estimation as he would in a real gas gauge application in a car.
These aging and environmental factors must therefore be taken into account if an accurate estimate is required.

Without the aforementioned circuitry, I guess we are lucky to have the extended recycling time to give us the heads up on battery condition. I was just trying to remember- is there any cameras or video cameras that have a "battery is dying" indicator light in the viewfinder? I can't seem to recall- if there are cameras with that feature, they must incorporate the technologies which you have pointed out.

I have here a battery catalog from a Canadian distributer- it seems that there are many hundreds if not thousands of battery configurations, chemical types and applications- medical- communications- appliances- photographic (camera, motor drives, meters, accessories and flash units) and even units with military specification for space flight and aviation applications and of course computers. The variety of charging rates, times, memory issues as well as the voltage and amp/hour specs is mind boggling.

I am a Lumadyne user for wedding assignments. I have 12 units running and when battery replacement time came, I used to consider taking out a second mortgage on the house. Each factory made pack, a cluster of sub-c Ni-cads was well over $200 plus shipping from their plant in Florida. I checked out my catalog and found that there are simple one piece Gel-Cells (sealed lead-acid) batteries that would fit into the flash units- they cost around $50 each and I made my own chargers. Surprisingly, they are longer lasting per duty cycle and in all over longevity. They are originally designed for hallway emergency lighting. Theses batteries are used to be on trickle charge all the time whiteout any memory or overheating problems. My batteries ore on trickle all the time and always topped off for immediate use. I get up to 400 full (200 w/s) power flashes per charge and change the cells about once every 6 years.

Regards, Ed

[Eero Makela]

Ed, the Nikon D300 actually keeps track of the number of shutter clicks it has had since the battery was recharged and also has a Percentage of power left. Also has another scale for the life of the battery a scale of 0-4 once it hits 4 it means battery needs to tossed and replaced with new one. A friend with a D80 Nikon has the same battery as my D300 and when We but his battery in my camera it showed the shutter and life and % remaining for his battery. The actual D80 does not have this feature.

From what I understand the battery has all the smarts and it has 3 contacts on it. I guess that is how it sends the data to the camera.

[brian.austin]

Originally Posted by Ed Shapiro

The variety of charging rates, times, memory issues as well as the voltage and amp/hour specs is mind boggling.

Yeah, I know. It used to drive me nuts when building robots and automated vehicles as a hobby. If we could get a sustainable charge for a power system that generated similar power curves as a gasoline engine, the world would be a much, much different place.

Someday...

[generic]

:someday....

yep, it'll probably be called a nuclear power cell

and last the life of the vehicle.

[Harry]

"Matter can neither be created or destroyed." It takes energy to make energy, at least until physics is proven wrong.

The nuclear powered vehicle is a possibility, it's the shielding that's the problem.

Electric powered cars are a possibility and a reality, people just don't take into account what it actually costs to recharge one from a plug in, current solar cell activity is still way behind where it probably could be.

[brian.austin]

Originally Posted by Harry

Electric powered cars are a possibility and a reality, people just don't take into account what it actually costs to recharge one from a plug in, current solar cell activity is still way behind where it probably could be.

A CA electric car manufacturer says $1 to $2 per night. And that's on CA power rates.

Given the efficiencies and power to weight issues, electric's biggest drawback is range. They can be fast, run amenities like a/c, and are very comfortable. There are no charging stations, though, and solar cannot replace the power fast enough while driving.

[Harry]

Beautiful little machine, what do you think it's going to look like/weigh when the feds get done making it "safe" for the highway. You know they can't keep their hands off of things. That's the reason why a ton of fuel efficient vehicles aren't allowed on our roads here in the states.

[brian.austin]

Originally Posted by Harry

Beautiful little machine, what do you think it's going to look like/weigh when the feds get done making it "safe" for the highway. You know they can't keep their hands off of things. That's the reason why a ton of fuel efficient vehicles aren't allowed on our roads here in the states.

That's the fun part. This isn't a "car" and doesn't fall under the federal safety requirements for automobiles. It's classed as an enclosed motorcycle.

Their FAQ and online literature covers safety and what they are changing. It's actually passing independent tests to automobile standards right now in some categories.