I want this feature...

[Sunny]

Once the car is turned off, I would like to press something to prevent it from shutting down and keep recording on it's battery.
It'll be useful in cases where officer wants keys out of the ignition.
Won't work for cap versions nor with some dashcams that have horrible battery life but most will work fine for 5-10 minutes.
Yes, you can wait until it shuts off, power on and press record but that's a lot of things to do when officer is watching you.

 

[Daleg]

Just Hardwire it and use a pmp...keep the pmp main power switch in the on position...the cam will remain on while the ignition is off.

 

[DashCamMan]

The older cameras like the F500lhd had a large Nokia BL-5C battery and the camera could be set to run numerous minutes after power was removed. I believe there was a menu setting as well to define the time.

 

[Rajagra]

Might be better to use something like a mobius with power-off standby disabled, and turn it off manually when you feel like it.
Removes the possibility of forgetting to press a button when you need to. Also nothing for observers to notice you doing.

 

[Witness Auto Dash Cam]

It is better to clarify what kind of parking recording you need first.

Like keep recording the whole things between hours or just a motion detection for important event occurs.

For battery life, after you have hardwire the dash cam, you don't need to worry about the dash cam shut down or not but need to worry about will the dash cam takes all of your car battery.

So you have to consider dash cameras with low voltage cutoff. If you are considering a motion detection, for example like the Thinkware and Lukas, there are different models and easily for you to check out the videos no matter on screen, wifi or on pc.

 

[Dashmellow]

The older cameras like the F500lhd had a large Nokia BL-5C battery and the camera could be set to run numerous minutes after power was removed. I believe there was a menu setting as well to define the time.

My first dash cam, an AT-20 used exactly that same cell phone type battery and it would run quite a while after ignition shutdown if so desired. I liked having a big honking easily replaceable battery at the time. I bought that camera over five years ago and it saw hard use for a long time. It no longer really works but that original battery is still good.

Edit: I've thought of this issue too. As a result (and for other reasons) I usually carry a Mobius as a pocket cam that I sometimes use to record general voice memos. Otherwise, I often carry one of these little 8GB USB audio recorders (Love em). They look like a typical USB thumb drive. I figure if I ever get pulled over by a cop I would immediately announce that I have recording devices in my vehicle to keep my recording activities strictly legal but I would engage one of my recorders before the officer approaches my car. That way I can capture the audio of him directing me to turn off my ignition. If something unseemly or illegal happens during the traffic stop I will be able to document it regardless.

I highly recommend these inexpensive little USB audio recorders. You can record for hours and hours on a single charge and there is memory for more hours of recording than you will ever need. Check out http://www.chucklohr.com/ for lots of info about these things. (and mini cams like the Mobius or original 808 key fob cameras)

 

[Deleted member 46308]

@Dashmellow any thoughts on the quality and usefulness of these http://www.buymobius.com/collections/720p-number-16-808-keychain-cameras ?

 

[Dashmellow]

@Dashmellow any thoughts on the quality and usefulness of these http://www.buymobius.com/collections/720p-number-16-808-keychain-cameras ?

I have no personal experience with them but they were and may even still be very popular with RC enthusiasts as they are still for sale. These cameras are what eventually gave birth to the Mobius. Most of what I know about them is from the Chuck Lohr site I linked to above, specifically THIS page. I almost bought one of them and Techmoan sort of got his start reviewing them but then the Mobius appeared on the scene and I never looked back.

Techmoan has done quite a few reviews of these cameras (there are quite a few iterations) and you will find them on his site but this one is a good example.

 

[dash riposki]

Why not a modest battery inline in the power supply line that charges during normal operation?

 

[Dashmellow]

Why not a modest battery inline in the power supply line that charges during normal operation?

This comes up from time to time here on DCT and it depends on what kind of battery chemistry you are talking about but it has been established that it is unwise to charge a lithium-ion battery when it is being drained by a parasitic load as it puts a great deal of stress on the cells.

 

[country_hick]

I figure if I ever get pulled over by a cop I would immediately announce that I have recording devices in my vehicle to keep my recording activities strictly legal

You have no requirement to tell the police anything about recording them.

Glik v. Cunniffe, 655 F. 3d 78 - Court of Appeals, 1st Circuit 2011
"The First Amendment protects the right to gather information about what public officials do on public property, and specifically, a right to record matters of public interest."

In summary, though not unqualified, a citizen's right to film government officials, including law enforcement officers, in the discharge of their duties in a public space is a basic, vital, and well-established liberty safeguarded by the First Amendment.

 

[Dashmellow]

You have no requirement to tell the police anything about recording them.

Glik v. Cunniffe, 655 F. 3d 78 - Court of Appeals, 1st Circuit 2011
"The First Amendment protects the right to gather information about what public officials do on public property, and specifically, a right to record matters of public interest."

In summary, though not unqualified, a citizen's right to film government officials, including law enforcement officers, in the discharge of their duties in a public space is a basic, vital, and well-established liberty safeguarded by the First Amendment.

I'm aware of that case but I also know there can be issues with secretly recording audio in certain states if the other party has not first been informed. In some jurisdictions it comes down to what is called a "reasonable expectation of privacy". This case you mention involved someone filming an arrest in an open public place that he was not party to. Recording a police officer off to the side of the road who has stopped my vehicle with no one else around may be viewed differently by the courts in different states. I'm not a legal expert but I would prefer to inform a LEO right up front to avoid any sort of hassles. Also, the value of my method of disclosure is that if I've already recorded myself informing the officer that there are recording devices in my vehicle and he demands that I switch off the ignition, I have no problem continuing to record him with a hidden device even if he thinks I've shut down all my dash cams. This way I've covered my ass legally regardless of the outcome whatever jurisdiction I may be in, or perhaps even some prosecutor's interpretation of the law that would later have to get straightened out in court.

Edit: If I understand the ruling, you are referring to language that prohibits "enforcing wiretapping law against citizens openly recording public officials in public places."

So, recording a traffic stop where the LEO is not aware that recording is taking place may well be a different matter, legally speaking.

 

[country_hick]

A traffic stop is done on a public road. License plates can be read with license plate readers by the police because there is no expectation of privacy in public.

If we have no expectation of privacy in our cars on the road the police do not have the expectation either.

United States v. Knotts, 460 US 276 - Supreme Court 1983
A person traveling in an automobile on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another. When Petschen traveled over the public streets he voluntarily conveyed to anyone who wanted to look the fact that he was traveling over particular roads in a particular direction, the fact of whatever stops he made, and the fact of his final destination when he exited from public roads onto private property.

People v. Xinos, 192 Cal. App. 4th 637 - Cal: Court of Appeal, 6th Appellate Dist. 2011
A person traveling in an automobile on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another. When [the driver] traveled over the public streets he voluntarily conveyed to anyone who wanted to look the fact that he was traveling over particular roads in a particular direction, the fact of whatever stops he made, and the fact of his final destination when he exited from public roads onto private property."

In short, legal precedent says on a public way there is no expectation of privacy and that includes privacy for the cop who pulls you over.

 

[Rajagra]

This comes up from time to time here on DCT and it depends on what kind of battery chemistry you are talking about but it has been established that it is unwise to charge a lithium-ion battery when it is being drained by a parasitic load as it puts a great deal of stress on the cells.

I haven't read those threads, but I don't think that's true.
At any instant, a battery cell can be charging, discharging (powering something) or doing nothing (other than internal discharging.)

The idea that a cell can be taking in current while simultaneously sending out current doesn't hold water.
The nearest thing that might happen would be with a really, really bad charging circuit, e.g. unsmoothed rectified AC charging a battery which is powering a device. That would cause rapid charge/discharge cycles of the battery.
But we're talking DC circuitry, with a huge car battery smoothing everything out. In such a situation current going to a device connected to a battery will merely cause reduced charging. Or if it takes enough current, will cause discharging.

There may be arguments against what I've said, but the important point is you could easily design a circuit that ties together car power, a secondary battery, and a device to be powered in a graceful way.

 

[Dashmellow]

A traffic stop is done on a public road. License plates can be read with license plate readers by the police because there is no expectation of privacy in public.

If we have no expectation of privacy in our cars on the road the police do not have the expectation either.

United States v. Knotts, 460 US 276 - Supreme Court 1983
A person traveling in an automobile on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another. When Petschen traveled over the public streets he voluntarily conveyed to anyone who wanted to look the fact that he was traveling over particular roads in a particular direction, the fact of whatever stops he made, and the fact of his final destination when he exited from public roads onto private property.

People v. Xinos, 192 Cal. App. 4th 637 - Cal: Court of Appeal, 6th Appellate Dist. 2011
A person traveling in an automobile on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another. When [the driver] traveled over the public streets he voluntarily conveyed to anyone who wanted to look the fact that he was traveling over particular roads in a particular direction, the fact of whatever stops he made, and the fact of his final destination when he exited from public roads onto private property."

In short, legal precedent says on a public way there is no expectation of privacy and that includes privacy for the cop who pulls you over.

Having, no reasonable expectation of privacy "in his movements from one place to another" is not the same thing as recording a conversation without the other party being aware of it. Your arguments are a good example of what happens when people with no professional legal knowledge read stuff on the internet and reach conclusions that would probably get them laughed out of court.

Anyway, I plan to inform an officer that I am recording him if I get pulled over and you should do whatever you like too based on your own interpretation of the law.

I'm not even sure why this is an issue for you since you have been a vocal member of this forum for over a year now and you still don't even own a dash cam, so what's the point? The whole dash cam experience for you seems to be entirely vicarious. It's weird.

 

[JooVuu]

It wouldn't be a particularly hard feature to implement. In theory all the button does it just tell the camera not to shut down.

I'll ask our firmware team - we're not releasing any new features till about March or so but I'll see what we can do.

Cheers,

 

[Dashmellow]

I haven't read those threads, but I don't think that's true.
At any instant, a battery cell can be charging, discharging (powering something) or doing nothing (other than internal discharging.)

The idea that a cell can be taking in current while simultaneously sending out current doesn't hold water.
The nearest thing that might happen would be with a really, really bad charging circuit, e.g. unsmoothed rectified AC charging a battery which is powering a device. That would cause rapid charge/discharge cycles of the battery.
But we're talking DC circuitry, with a huge car battery smoothing everything out. In such a situation current going to a device connected to a battery will merely cause reduced charging. Or if it takes enough current, will cause discharging.

There may be arguments against what I've said, but the important point is you could easily design a circuit that ties together car power, a secondary battery, and a device to be powered in a graceful way.

I supposed I shouldn't be surprised at this point that you wouldn't take the time to read all the previous discussions on this subject before taking an opposing position. You appear to have ignored what was said as well.

Oddly enough you also appear to be offering a supportive contradictory statement when you say, "The idea that a cell can be taking in current while simultaneously sending out current doesn't hold water." That is absolutely correct and is the very reason that the issue here is not whether you can design a circuit that will accomplish what you want, it is a question of whether or not it is a wise thing to do. The reason it is not a wise thing to do is because the lithium-ion batteries that would be used for this "feature" should not be charged and discharged at the same time.

Remember, our discussion here is in response to @dash riposki's suggestion above, "Why not a modest battery inline in the power supply line that charges during normal operation?"

The issue (the one I believe you are ignoring) is the chemistry of the battery. It is simply an unwise idea to charge and discharge a battery pack simultaneously regardless of circuit design. Most people refer to this as pass-through charging.

In a lithium-ion rechargeable battery both the positive electrode (cathode) and the negative electrode (anode) bind lithium ions from lithium oxide that migrate back and forth between the cathode and anode during the charging and discharging process. When the battery is discharging, the lithium ions moving back to the cathode release energy in the process and this is how the battery powers your device. When the battery is being charged, the lithium ions migrate back through the electrolyte in the other direction towards the anode.

So, if you charge the battery while it is simultaneously discharging, then you are trying to force the lithium ions to move in opposite directions through the electrolyte at the same time which will cause a lot of stress to the cells and will eventually lead to lithium metal plating which is the dangerous process than can ultimately cause a thermal runaway, but for the most part will simply shorten the life of the battery dramatically and reduce capacity.

Also, according to Isidor Buchmann, the well known battery scientist behind Battery University, "A portable device must be turned off during charge. This allows the battery to reach the set threshold voltage unhindered, and enables terminating charge on low current. A parasitic load confuses the charger by depressing the battery voltage and preventing the current in the saturation stage to drop low. A battery may be fully charged, but the prevailing conditions prompt a continued charge. This causes undue battery stress and compromises safety."

 

[ddnut]

Also, according to Isidor Buchmann, the well known battery scientist behind Battery University, "A portable device must be turned off during charge. This allows the battery to reach the set threshold voltage unhindered, and enables terminating charge on low current. A parasitic load confuses the charger by depressing the battery voltage and preventing the current in the saturation stage to drop low. A battery may be fully charged, but the prevailing conditions prompt a continued charge. This causes undue battery stress and compromises safety."

In that case, we ought to turn our smartphones and laptops when recharging. I figured that turning the device off would allow the battery to recharge faster but I did not know that this practice can extend the battery life as well. Based on that website I will have to look closer at my laptop battery to see if it is worth removing it or not when my laptop is docked.

 

[Sunny]

Definitely, turning devices off while charging will be charged quicker and probably make battery last longer but I can't do that for phones.
I'd rather replace battery than having a downtime without phone for hours at a time.

 

[Dashmellow]

Definitely, turning devices off while charging will be charged quicker and probably make battery last longer but I can't do that for phones.
I'd rather replace battery than having a downtime without phone for hours at a time.

"probably make the battery last longer"?

Well, at any rate, there is no need to actually turn off your phone (or tablet) while charging. You just shouldn't be using it for long periods of time while it is charging.

Smartphones and tablets actually use sophisticated battery management techniques that do allow them to be used and charged at the same time, up to a point, but for overall battery longevity and safety it's still not a good idea. You simply cannot change the chemistry and physics of the charging/discharging process described above.