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Bmpcc 4k Voltage

PostPosted: Thu Apr 04, 2019 3:28 pm
by docdoc
Hello,

i want to power my freshly arrived pocket 4k with a usual V-Mount. In the tech specs it says the DC takes 12 - 20 V. So the 14.4V of the V-Mount should be fine, right? Or do i need a transformer which gives only 12V? Because on the camera it says clearly 12V.

I am also a little confused, as the camera runs with 7.2V Batteries, the DC should also take 7.2, or not?

Re: Bmpcc 4k Voltage

PostPosted: Thu Apr 04, 2019 4:21 pm
by rick.lang
The 14.4VDC is fine as the DC will take inputs of at least 12VDC. As your V-Mount battery loses voltage, the camera may even function a little below 12VDC.

The 2-pin DC will not function with 7.2VDC power from a battery.


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Re: Bmpcc 4k Voltage

PostPosted: Sun Apr 07, 2019 7:26 pm
by docdoc
Thank you. I was just wondering because Lanparte is offering a dedicated set with something that looks like a transformator for V-Mounts: Regulated 12V D-tap Power Cable for BMPCC-4K Camera

Re: Bmpcc 4k Voltage

PostPosted: Sun Apr 07, 2019 7:31 pm
by docdoc
Edit: Quote from Lanparte: "Special voltage control component inside regulates input voltage to meet the requirement of BMPCC 4K camera."

Re: Bmpcc 4k Voltage

PostPosted: Mon Apr 08, 2019 8:06 pm
by rick.lang
True, but I don’t think that connector goes as low as 7.2VDC. Someone may post if they’re successful.


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Re: Bmpcc 4k Voltage

PostPosted: Mon Apr 08, 2019 11:03 pm
by michaeldhead

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 1:24 pm
by Johannes Jonsson
The weipu input is for minimum 10.8v up to 20v ONLY. lower then 10.8v can damage the camera with the time of use. equipment usually only allow around 10% variation from given voltage for very short moment.

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 3:55 pm
by Niklas Olofsson
In the Manual from May this year it says:

Battery slot takes between: 6.2v - 10v
External Input between: 10.8v - 20v

and if you use external power it is recommended to remove the battery.


...but I found this!!
And I wonder how that worked out for him... powered the Camera with NP-F battery (7.2v) via the external input.

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 4:43 pm
by Denny Smith
Not a good idea. If you are looking for a compact battery, check out Sijan’s battery kit. While it was originally designed for the Micro camera, it outputs 14.5 VDC, is compact and has three voltage taps out, one of which can power the Pocket 4K via the external input. Just add BMDs battery cable kit, which has the correct cable. This battery has several mounting options, and has 1/4x20 tapped mounting points on it also. I got one, and it works great.
Cheers

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 4:50 pm
by Niklas Olofsson
Denny Smith wrote:Not a good idea. If you are looking for a compact battery, check out Sijan’s battery kit. While it was originally designed for the Micro camera, it outputs 14.5 VDC, is compact and has three voltage taps out, one of which can power the Pocket 4K via the external input. Just add BMDs battery cable kit, which has the correct cable. This battery has several mounting options, and has 1/4x20 tapped mounting points on it also. I got one, and it works great.
Cheers



... yes, I know his Battery... it is great.

Just saw that YouTube Video and wonder how it worked with only 7.2v into the external input.

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 5:07 pm
by Spencer Morris
[quote]and if you use external power it is recommended to remove the battery.
[/quote

I just looked through the manual in the "turning your camera on" section and didn't see this. Where is it from?

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 5:12 pm
by Dmytro Shijan
Niklas Olofsson wrote:In the Manual from May this year it says:

Battery slot takes between: 6.2v - 10v
External Input between: 10.8v - 20v

and if you use external power it is recommended to remove the battery.


...but I found this!!
And I wonder how that worked out for him... powered the Camera with NP-F battery (7.2v) via the external input.



Pocket4K Camera power consumption varies a lot depending camera settings (frame rate, codec, monitor brightness)
NP-F battery output voltage range: 5V min., 7.4V normal, 8.4V max.
V-mount output voltage range: 10V min., 14.8V normal, 16.8V max.

Camera voltage tech specs are usually based on recommended real life safe limit at maximal possible power consumption (22W)
Too low voltage may overload and damage internal camera DC-DC regulator over time.
P4K Camera similar to any other device have have build-in DC-DC voltage regulator, so there is no need for additional external voltage regulator.
Any additional external DC-DC step down voltage regulator will waste about 10% of usable battery capacity.
It seems Feelworld MA5 have build-in step-up voltage regulator and output fixed 8.4V

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 5:16 pm
by Denny Smith
Yes, and just because someone posts a UTube video showing a 7.4VDC battery connect to a Pocket 4K works, does not make it a good idea to do. Always use a battery that has the correct voltage for the camera you are using. ;)
Cheers

Re: Bmpcc 4k Voltage

PostPosted: Sun Jun 23, 2019 5:21 pm
by Dmytro Shijan
From tech specs it seems Feelworld MA5 have build-in step-up voltage regulator and output fixed 8.4V.

Re: Bmpcc 4k Voltage

PostPosted: Mon Jul 08, 2019 6:13 pm
by ishootyou.com
Would I be able to power the camera with drone batteries? They have a nominal voltage of 11.4V, 3830mAh, 43.6Wh

I have plenty of those and the numbers seem right, hence my question.

Re: Bmpcc 4k Voltage

PostPosted: Mon Jul 08, 2019 7:28 pm
by reman1964
Interesting info! Tilta makes a plate that takes NPF and outputs via 2 ports 12v or 7.4v. I just got mine and put a PowerExtra 960/970 7.4v 8800mAh 65Wh battery in and used an Alvin's Cables Power Cable for BMPCC4K... Powered on and shows AC. I am hoping that this is okay!! And I should NOT keep an internal battery in OR is that also okay?

Re: Bmpcc 4k Voltage

PostPosted: Tue Jul 09, 2019 9:36 am
by eijitokyo
Dmitry Shijan wrote:From tech specs it seems Feelworld MA5 have build-in step-up voltage regulator and output fixed 8.4V.

So, is it OK using NP-F battery via Feelworld MA5?
I'm trying to use this setting via a dummy battery.

eijitokyo

Re: Bmpcc 4k Voltage

PostPosted: Tue Jul 09, 2019 11:29 am
by eijitokyo
and,
Any comments appreciated.
Thanks in advance.

Re: Bmpcc 4k Voltage

PostPosted: Tue Jul 09, 2019 2:57 pm
by reman1964
Australian Image wrote:I've always kept an original Canon battery in mine while powering off a V-lock. If I have to change the V-lock battery for any reason, the internal battery acts as an UPS during the change.


Soooo.... the million dollar question... Is it safe to power via 12v port AND have an internal battery? I guess there might be separate answers depending on the source so maybe YES if V mount with lots of power and volts and NO/YES if running an NPF that has its 7.4v voltage upscaled to 12v?

[ I really wish BM would make an official statement of what works and what does not and WHY. ]

Bmpcc 4k Voltage

PostPosted: Tue Jul 09, 2019 5:08 pm
by rick.lang
I may be mistaken, but I believe BMD has said they don’t recommend having the internal battery in the camera when powering from an external battery. The concern is that it may be that the internal battery will try to draw more power from the external battery than the external battery is designed to supply. Not being an electrical engineer, I don’t know if that is only an issue with unregulated power supplies. In reality many people will still leave the internal battery in place as an insurance policy if the other power provided should fail or while you mount a fresh external battery.

Edit
As noted below, this approach is what I’ll do when I have a large battery such as the Cinegears 250Wh powering the BMPCC4K. I don’t plan to purchase another battery power source as I can go about 2 ½ hours with the internal genuine batteries or perhaps 9 hours with the Cinegears.

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Re: Bmpcc 4k Voltage

PostPosted: Tue Jul 09, 2019 8:57 pm
by reman1964
Australian Image wrote:
reman1964 wrote:
Australian Image wrote:I've always kept an original Canon battery in mine while powering off a V-lock. If I have to change the V-lock battery for any reason, the internal battery acts as an UPS during the change.


Soooo.... the million dollar question... Is it safe to power via 12v port AND have an internal battery? I guess there might be separate answers depending on the source so maybe YES if V mount with lots of power and volts and NO/YES if running an NPF that has its 7.4v voltage upscaled to 12v?

[ I really wish BM would make an official statement of what works and what does not and WHY. ]


I've been doing it this way since Oct 2108 when I received BMPCC4k. The moment I turn on my V-lock, the camera goes to AC mode. I can't imagine why the camera would have been designed to not work this way.


Ahhhh! But is that because yours is with a V-Lock which outputs more power (14v?) than an NPF upscaled to 12v (my portable rig) and can handle the strain ORRRRR my version should be fine too? MANY THANKS!!

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 10, 2019 1:21 pm
by reman1964
rick.lang wrote:I may be mistaken, but I believe BMD has said they don’t recommend having the internal battery in the camera when powering from an external battery. The concern is that it may be that the internal battery will try to draw more power from the external battery than the external battery is designed to supply. Not being an electrical engineer, I don’t know if that is only an issue with unregulated power supplies. In reality many people will still leave the internal battery in place as an insurance policy if the other power provided should fail or while you mount a fresh external battery.

Edit
As noted below, this approach is what I’ll do when I have a large battery such as the Cinegears 250Wh powering the BMPCC4K. I don’t plan to purchase another battery power source as I can go about 2 ½ hours with the internal genuine batteries or perhaps 9 hours with the Cinegears.

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I appreciate your responses! I guess I am worried that I might damage the 4k... I do not have a powerful V mount at this time. I really wish BM would clarify the many different options and WHY something can or cannot be done. :? :shock: :D

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 10, 2019 2:26 pm
by Craig Seeman
reman1964 wrote:Interesting info! Tilta makes a plate that takes NPF and outputs via 2 ports 12v or 7.4v. I just got mine and put a PowerExtra 960/970 7.4v 8800mAh 65Wh battery in and used an Alvin's Cables Power Cable for BMPCC4K... Powered on and shows AC. I am hoping that this is okay!! And I should NOT keep an internal battery in OR is that also okay?


I'm using Tilta side handle with PowerExtrea 960/970. I called BMD support and they said rather decisively DO NOT keep Canon battery installed. Support said there's risk to damaging the camera when it's powered off and the camera uses the NPF battery to try to charge the Canon battery.

Page 27 of the User Guide notes:
Screen Shot 2019-07-10 at 10.23.54 AM.png
Do not leave LP-E6 in with Custom Power solutions
Screen Shot 2019-07-10 at 10.23.54 AM.png (152.69 KiB) Viewed 60692 times

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 10, 2019 2:43 pm
by Craig Seeman
Testing Powerextra NP-F960/970, 7.4v, 8800mAh, 65.12Wh battery with
Tilta Side Power Handle.
Recording to Samsung T5 SSD,
Lens Panasonic 12-35mm v1 with OIS enabled.
Screen 100% brightness
Did not have LP6 battery installed.
Runtime 2 hours 52 minutes 12 seconds.
Thought people would be interested.
Camera is probably using about 22W which seems to match the User Guide's explanation.

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 10, 2019 4:56 pm
by rick.lang
Craig, thanks for the posts. Definitely not an issue for me when using the large V-Mount/Gold mount batteries through the external power input port.

Nice to see the camera is proving the runtime you would expect. After hearing so much bad news about the BMD battery, I was surprised I almost made it through the July 1st evening shoot. Easy to pop in the genuine batteries as needed.


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Re: Bmpcc 4k Voltage

PostPosted: Thu Jul 11, 2019 12:51 pm
by reman1964
Sooooo

I received an answer from tech support on this question and here is what they said:

Thanks for getting in touch with us.

It is perfectly acceptable to use the internal battery of the Pocket Cinema Camera 4K in addition to an external power source (battery or main power). This allows one to change external power sources on the fly, without having to power down the camera. It also acts as a safety net in case the external power source is cut or runs dry.

Our recommended input levels are as follows:
Internal battery connection - 6.2V to 10V max
DC input - 10.8v to 20V max

As long as your power option falls within the acceptable input ranges, we'd expect it to work with the camera.

I hope this information helps, but please let me know if you have any further questions.

Kind regards,
Technical Support Representative
Blackmagic Design Inc.



It seems that some clarification is needed... I will further investigate.

Re: Bmpcc 4k Voltage

PostPosted: Thu Jul 11, 2019 1:11 pm
by rick.lang
That clearly ruled out the DIY solution using 8.4VDC.


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Re: Bmpcc 4k Voltage

PostPosted: Thu Jul 11, 2019 1:15 pm
by reman1964
rick.lang wrote:That clearly ruled out the DIY solution using 8.4VDC.
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I agree although my setup provides 12V to the port. I would think that the internal circuitry would detect lower than 30w (I have no idea what the Tilta 12V power supplies in terms of Watts) and simply not allow charging/trickle charging of an internal battery?

Re: Bmpcc 4k Voltage

PostPosted: Mon Jul 29, 2019 2:35 pm
by Lexington
I found a plate that takes an NP-F 7.4 volt battery and steps up the voltage to 12v. According BMD, the BMPCC4K can take a charge from an exterior source from 12v – 20v. Is there something I’m missing here (amps) or should I be OK powering my BMPCC4K from this source? I’m a writer turned film maker, not an electrical guy at all, any suggestions would be most appreciated.

Re: Bmpcc 4k Voltage

PostPosted: Tue Jul 30, 2019 8:02 pm
by reman1964
Okay...
NOT GOOD NEWS:

I asked the support people to verify with their engineers and here is what was said to me from BM:

Hello,

It looks like I was incorrect- engineering was able to confirm that the guidance in the manual is correct. As such, the official guidance is that you remove the internal battery when using your external power source.

I do apologize for the inconvenience, but please let me know if you have any other questions.


Sooooo....
No go. Still makes no sense as to why the circuitry does not detect power parameters and either charge or not and if power from 12V gets interrupted then switch to internal... :(

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 2:08 pm
by Lexington
Does anyone know if two Sony NP-F batteries wired in parallel will safely power the BMPCC 4K?

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 4:00 pm
by youlikeny
Lexington wrote:Does anyone know if two Sony NP-F batteries wired in parallel will safely power the BMPCC 4K?

Even a single NP-F is enough to power the Pocket4K for a few hours..

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 4:35 pm
by Lexington
I'm not an electric guy buy any means so please pardon my ignorance, will the lower amps and watts from the NP-F damage the camera?

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 5:35 pm
by youlikeny
There is not a definitive answer from Blackmagic but there are dozens of people out there (me included) who have been using NP-F plates to power the Pocket4K for months without any issue.
Major accessories manufacturers like Tilta, Indipro, HawkWood and Smallrig even make single NP-F plates to power specifically the Pocket4K...

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 6:39 pm
by reman1964
1) The engineers (through the tech support people) at BM stated Using an NPF battery IS OKAY either as a dummy 7-8v or upconverted to 12v via a plate such as the Tilta.

2) HOWEVER the engineers (through the tech support people) at BM stated that you cannot have an internal battery in at the same time as being powered by an NPF via 12v.

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 6:44 pm
by Lexington
reman1964 - THANK YOU!

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 6:58 pm
by reman1964
Lexington wrote:reman1964 - THANK YOU!

My pleasure. Hopefully they/BM will have better written explanation, reasoning and advice ASAP with many different scenarios so we know how not to hurt our pocket babies. :D

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 9:07 pm
by reman1964
Australian Image wrote:I honestly think that Blackmagic should provide a better explanation than what they have. To me its sounds like an administratively easy answer to cover all bases.

Has Blackmagic stated that you can't use the camera with the mains power charger connected and a battery installed? No. On page 5 of the BMPCC4K manual it states that you can:

The included 100-240 volt plug pack can be used to simultaneously power the camera and charge the LP-E6 battery.


So what exactly is the difference between the mains power pack (12V) and a V-Lock (14.8V) or other battery pack that provides the same voltage output?


I am guessing it has something to do with the NPF battery being upscaled to 12v and therefore not providing enough watts (??) to do both jobs... While a wall plug supplies much more power... [??]

Re: Bmpcc 4k Voltage

PostPosted: Wed Jul 31, 2019 9:27 pm
by reman1964
Australian Image wrote:
reman1964 wrote:I am guessing it has something to do with the NPF battery being upscaled to 12v and therefore not providing enough watts (??) to do both jobs... While a wall plug supplies much more power... [??]


The mains provides no more voltage or amps than a V-lock. So I suspect that it's just an administrative policy in case someone tries to use inappropriate external power such as lower than 12V battery packs thinking that, because the NP-E6 is just 7.2V, you can use anything of the same or higher voltage.


Hmmmm.... The problem they mentioned was the lack of watts (30+) from an NPF. A V-mount option was not asked by me. Grrrr. BM please help us. :) :D :cry:

Re: Bmpcc 4k Voltage

PostPosted: Thu Aug 01, 2019 7:54 am
by Boscom
I think the problem is if you are using an NPF via the 12v input, you would need to insure any battery in the camera is fully charged, so you wont get excessive additional current going to charging that battery.

Before I saw this post, I ran a test on a couple of new NPF-990's I had just received. With a Tilta battery plate I was powering the camera from the plates 12v output and a 5" external monitor from the 7v output. I ran one NPF battery with no internal camara battery, continuously (no recording) and got 3 1/2 hours. The next battery I put a FULLY CHARGED, LP-E6 in and got the same running time within a few minutes.

Re: Bmpcc 4k Voltage

PostPosted: Thu Aug 01, 2019 2:13 pm
by reman1964
Boscom wrote:I think the problem is if you are using an NPF via the 12v input, you would need to insure any battery in the camera is fully charged, so you wont get excessive additional current going to charging that battery.

Before I saw this post, I ran a test on a couple of new NPF-990's I had just received. With a Tilta battery plate I was powering the camera from the plates 12v output and a 5" external monitor from the 7v output. I ran one NPF battery with no internal camera battery, continuously (no recording) and got 3 1/2 hours. The next battery I put a FULLY CHARGED, LP-E6 in and got the same running time within a few minutes.


I believe the issue is that although you are able to do what you are doing... it is that the internal circuitry can be damaged by that... [which was not explained as to why except that the wattage might not be up to the job and hurt the electronics.]

Re: Bmpcc 4k Voltage

PostPosted: Fri Aug 02, 2019 12:35 pm
by BarryStep
So, when using a V-Mount battery, we can leave the internal battery in, and it will charge. When using a NPF, the internal battery should be taken out. Is this the conclusion that has been reached?

To add another question: Is anyone using the Moza Air 2 (or other gimbal) to power the BMPCC4k? I've read that you can also charge the internal battery when powering through a gimbal? There are, apparently, two versions of the Moza Air 2: the first version, which had 12V out, and the later version, which I have, which is 16.8V out. I read that powering cameras with the early 12V version could potential fry the gimbal.

Re: Bmpcc 4k Voltage

PostPosted: Fri Aug 02, 2019 3:58 pm
by reman1964
BarryStep wrote:So, when using a V-Mount battery, we can leave the internal battery in, and it will charge. When using a NPF, the internal battery should be taken out. Is this the conclusion that has been reached?

To add another question: Is anyone using the Moza Air 2 (or other gimbal) to power the BMPCC4k? I've read that you can also charge the internal battery when powering through a gimbal? There are, apparently, two versions of the Moza Air 2: the first version, which had 12V out, and the later version, which I have, which is 16.8V out. I read that powering cameras with the early 12V version could potential fry the gimbal.

Hi Barry. There is no determination on a V mount as my questions to BM revolved around 12v NPF power. Ask their support to ask the engineers about the V options... (and hopefully post answer here)
The power port handles a range of power I think from 11v to 20v BUT ASK BM.

Re: Bmpcc 4k Voltage

PostPosted: Thu Aug 22, 2019 2:00 am
by Naqvi_aa
Seems like finding a good solution to powering the P4K is quite a challenge. I'm looking for a solution to powering the P4K and my Feelworld monitor, hopefully with the same NPF battery. some plates that you can find on ebay have a dummy battery and a 7.4V out as well. Would this work without damaging the camera? Also, how about a NPF battery straight into the monitor and using the monitor's 8.4V out to power the camera with a dummy battery? This makes the monitor heavy though :(

Plus these plates seem very cheaply constructed. The new Tilta plate seems promising.

Initially I was very interested in using the NPF battery plate with a weipu 12v output and a 7.4v output for the monitor and have a lp6 in the camera body, but seems like that's sort of a no no unless you don't fear roasting your camera in the process.

Re: Bmpcc 4k Voltage

PostPosted: Thu Aug 22, 2019 4:43 pm
by Denny Smith
You could use D itry’s New battery module, it can output 16.5VDC, and has three power taps, and is not much larger than the Sony adapter plates. While it was designed for a Micro ca era, yiu can use the LPE6 dummy mount to attach the battery pack to the monitor, or without the batty plate, bolt it directly to a cage.
See: viewtopic.php?f=2&t=71520&p=531401&hilit=Battery+Module+by+RADIOPROEKTOR#p531401

Re: Bmpcc 4k Voltage

PostPosted: Thu Aug 22, 2019 6:26 pm
by Peter J. DeCrescenzo
Naqvi_aa wrote:Seems like finding a good solution to powering the P4K is quite a challenge. ...


Um, no it's not. Using an NPF battery creates unnecessary challenges.

There are literally hundreds of off-the-shelf solutions available. Many are relatively inexpensive, such as:
https://www.bhphotovideo.com/c/product/ ... 2_pin.html

I use Anton-Bauer gold-mount batteries, but there are hundreds of V-mount solutions which work just as well (and are often less-expensive than AB), and new smaller-size V-mount batteries, too.

Re: Bmpcc 4k Voltage

PostPosted: Fri Jan 03, 2020 8:57 am
by Jan Kluczewitz
This as usual is a great conversation.

I'm working on a custom solution as well. My question is which voltage/input is the most efficient. I understand from this thread that the camera internally runs on 12V at least some parts. So the input via a dummy battery will be stepped up to 12V and the input via the 12V will be modified accordingly (stepped up if under 12V and stepped down if over 12V). Is that right? So (external conversions aside) the ideal solution would be to feed the camera 12V into the 12V input. Anything else would be converted and that's why would not be as efficient.

My general idea is to use battery pack cases with Sony NP-F mounts for AA batteries and NP-F battery plates. I can find three varieties of the cases (4xAA, 6xAA and 8xAA). Since I don't only want to use them for the camera but also for my sound gear, the monitor and such I am thinking what would be the most flexible and also most efficient. Also this setup would allow me to use NP-F batteries and with adapter plates also Canon LP-E6 batteries. One big point for me is that I if I use the AA batteries that I can use them for anything else and I can charge and replace them individually which should make for a longer lifetime.

Re: Bmpcc 4k Voltage

PostPosted: Fri Jan 03, 2020 2:12 pm
by Michael_Andreas
Jan Kluczewitz wrote:So the input via a dummy battery will be stepped up to 12V .....


After you ruin your camera by doing this, perhaps you'll consult the Manual and read what the rated voltage range for the battery connection is.

and the input via the 12V will be modified accordingly (stepped up if under 12V and stepped down if over 12V). Is that right? So (external conversions aside) the ideal solution would be to feed the camera 12V into the 12V input. Anything else would be converted and that's why would not be as efficient.


The Manual also gives the rated voltage range for the DC Input (Your term "12V input".)

My general idea is to use battery pack cases with Sony NP-F mounts for AA batteries and NP-F battery plates. I can find three varieties of the cases (4xAA, 6xAA and 8xAA). ....... One big point for me is that I if I use the AA batteries that I can use them for anything else and I can charge and replace them individually which should make for a longer lifetime.


The Manual also gives the power consumption for the camera, which is up to 30W. How many AA batteries do you need to supply voltage in the specified range? And will these AA batteries be capable of supplying the required power?

My recommendation is that you buy an off-the-shelf properly engineered power solution.

Re: Bmpcc 4k Voltage

PostPosted: Fri Jan 03, 2020 5:36 pm
by Jan Kluczewitz
Thanks you for your input (on whatever voltage you gave it).

After you ruin your camera by doing this, perhaps you'll consult the Manual and read what the rated voltage range for the battery connection is.


I've read this thread and am aware of what the voltage range is for this input and also for the battery input. I was asking about what happens inside the camera. So as far as I understand the camera inside needs 12V (at least in part). So the voltage from the battery input has to be stepped up by the camera (not me). In that case it would be less efficient as for example 10xAA (more or less 12V) for the power input. If the camera works inside with 7,2V and the regular power input is fed let's say 15V it has to be stepped down and then also energy is lost for my purposes (because it's converted into heat).

The thoughs about the current/watts are valid and have to be considered, I agree.

Re: Bmpcc 4k Voltage

PostPosted: Fri Jan 03, 2020 6:22 pm
by Denny Smith
You got this all wrong my friend. First of all, 12vdc is the nominal voltage, meaning average power required. A 12vdc Battery does not output 12vdc, it can output 14.5 VDC fully charged for example (depending on the battery type, it can go as high as 16.5 VDC) and the voltage drops during discharge. Once the external power drops below 10vdc, the Pocket camera gives a low voltage warning, and shuts down when the battery can not linger provide the minimum power requirements. Leaving a battery in the camera whilst the external power is applied, the camera will take part of that power input to charge up, and maintain the internal battery charge. So leaving a battery in the camera will reduce the run time of the external battery.

BMD says the voltage requirements are: Our recommended input levels are as follows:
Internal battery connection - 6.2V to 10VDC max
DC input - 10.8Vto 20VDC max


Go below these requirements and the camera will shut down. Exceed these requirements and component damage may result. But these are the voltage requirements for the camera’s DC-DC power supply, which in turns converts the voltage to what the camera requires, different, as internal components run at different voltages, anywhere from 3.2 VDC to 6 VDC for example (not actual requirements). USB power used to supply around 5 vdc, while the newer USB ports (post 2007) can supply up to 12 VDC, which is what the new iPhones run on. But this does not mean the device runs on 5 or 12 VDC, only that it’s power supply requires this nominal voltage to run properly.

The actual voltage requirements inside the Pocket 4K, or any camera, is not s simple single voltage, the camera’s DC-DC power supply takes the input voltage and converts it to what each component needs. The camera is a mini computer, which has one or more circuit power requirements, the LCD screen a different voltage, whilst the cooling system may need a different voltage yet. You are correct, that each time a voltage source is converted up (has more loss) or down, there is power loss cure to the conversion. But their is no single “magical” voltage level you could feed the camera to reduce this conversion process, any power applied to either the external or internal battery requires conversion to the varied voltage levels required internally.

Will a BMD Camera run on less voltage? Sometimes, but it is not a good practice to do so. I would use BMD’s recommendations and not try to second guess what the camera actually needs. I would suggest you re-read Dmitry’s and the BMD responses posted in this discussion. ;)
Cheers