Battery Life

[Reptorama]

Does anyone know how long the battery lasts for when recording HD video? Is it possible to run from a mains power source?

[Illkane]

I don't know and I am also interested in.

If every 5 minutes of HD movie will use 2 Gb : so, 20 minutes par 8Gb card... so, 3 cards per hour...

How many batteries per hour of HD movies ?
The answer already afraids me !

Who's know it ?

[kevm14]

If every 5 minutes of HD movie will use 2 Gb :

It's closer to 1/4 of that per 5 minutes.

[Andrew Brinkhaus]

roughly 600MB for 5 minutes

[Reptorama]

I'm interested about the battery life because I was thinking of recording some interviews with it but I'm also a little concerned about damaging the camera through overheating (with the 5 minute cut off).

I think the D90 could be great for shooting fiction as the 5 minute limit should never really be bumped up against.

[Andrew Brinkhaus]

Some Nikon reps have said the time limit has nothing to do with overheating, its a coding limitation, others have said it is a sensor protection feature, to protect from eventual overheating. So not sure the actual reason...

[Thebes]

I think the limit probably is for overheating. I had mine overheat today on a tripod while I was in front of the camera. It shut itself off without messing up the video it had already recorded. Ambient temp was about 72F, under a single flo bank, no hands on the camera. I could see that it might overheat quicker handheld under the So Cal sun.

I had been shooting for about an hour in 2-4 minute takes with Live View on almost the entire time. I still seem to have had plenty of battery left, the on camera display was only down one segment from a full battery.

[Reptorama]

Unfortunately I don't think I have to worry about SoCal sun causing the camera to overheat. I like in the delightfully overcast and cool (temperature-wise) UK.

Its good to hear that the battery life wouldn't pose a problem (although now I can worry about overheating) :-)

[jbierling]

Sorry to dig up an old thread but does anyone have a batter idea now how many minutes of video a D90 can take on one battery (how many 5 minute clips)?

[mattsand]

it's not recording that eats batteries, neither is it recording that overheats the sensor, it's the live view itself. for a ballpark figure we shot 3 hours of footage yesterday and used up 4 batteries. generally if you have 4 batteries you can shoot normally for an entire day in my experience, with 2 batteries you're probably fine too as long as you're not continuously in live view (i tend to be and use two cameras that i switch between when one overheats). we had an 18 hour day recently where we shot around 5 hours of footage, and then we had to recharge the batteries towards the end.

/matt

[taubkin]

Yeah, two batteries minimal, for a shooting day.

[artforme]

it's not recording that eats batteries, neither is it recording that overheats the sensor, it's the live view itself. for a ballpark figure we shot 3 hours of footage yesterday and used up 4 batteries. generally if you have 4 batteries you can shoot normally for an entire day in my experience, with 2 batteries you're probably fine too as long as you're not continuously in live view (i tend to be and use two cameras that i switch between when one overheats). we had an 18 hour day recently where we shot around 5 hours of footage, and then we had to recharge the batteries towards the end.

/matt

Good info! People get the buffer time confused with the overheating often in these forums. It is live view that can overheat the sensor, not the actual recording.

Either way, I agree that the D90 is more suited to preplanned or short spontaneous shots rather than long interview/documentary style shots.

[jbierling]

for a ballpark figure we shot 3 hours of footage yesterday and used up 4 batteries. generally if you have 4 batteries you can shoot normally for an entire day in my experience, with 2 batteries you're probably fine too as long as you're not continuously in live view (i tend to be and use two cameras that i switch between when one overheats). we had an 18 hour day recently where we shot around 5 hours of footage, and then we had to recharge the batteries towards the end.

Great info, thanks.

[jbierling]

It is live view that can overheat the sensor, not the actual recording.

There's no way to turn off live view while recording right? If that's true, I guess I didn't see the need to make a distinction.

[mattsand]

it's like asking if it's possible to turn off the mic while recording audio. if you turn off the live view while recording what are you gonna record? a black frame? :-) what i'm saying is that you can overheat the camera and wear out batteries just as fast without ever hitting the rec button, hence the need for the distinction.

/matt

[jbierling]

it's like asking if it's possible to turn off the mic while recording audio. if you turn off the live view while recording what are you gonna record? a black frame? :-)

Well, there isn't always the need to see exactly what is being recorded, so if there was a way to turn off the monitor/screen it would save a bit of battery. It might be that its the screen that is the power draw, not liveview (let's say defined as mirror up and everything else "on" except for the actual screen) per say.

But I think we understand each other ;-)

[mattsand]

It might be that its the screen that is the power draw, not liveview
for sure, but it's not very likely in my opinion and it's certainly not what makes the sensor overheat, right? ;-)

/matt

[artforme]

Why I think it is important to make the distinction is so that people understand to turn off live view in between shots if they want to help prevent overheating. And this does not have anything to do with the 'writing the video buffer' time limit that you see in live view while recording. (This is my understanding of the matter at least...)

But I think we all are on a similar page; I'm just reiterating for other whom might appreciate it.

Also; I'm sure we all look forward to the day when this issue becomes obsolete with future generation technology. Although the 'buffer' time does not bother me with any projects I will be doing in the foreseeable future.

But I agree that having at least one back up battery is a must for any semi serious project. I must say I am pleasantly surprised by the battery life in the D90.