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Dissecting Blackmagic | Hardware Discussion

PostPosted: Sat Dec 12, 2015 12:06 am
by Csaba Nagy
Image

| Welcome to the Dissecting Blackmagic Thread! |
_________________________________________________________________________________________

I thought It might be a good idea to consolidate all the information we know about Blackmagic Camera's into a single thread. This includes, technical documentation, hardware, and general discussion about the Blackmagic Camera's ( specifically as it pertains to hardware. )

Please share any pictures of the camera's hardware, personal experiences or information you have learned regarding technical aspects of the camera and its operation.

Thanks in advance to those who contribute.
_________________________________________________________________________________________

Re: Dissecting Blackmagic

PostPosted: Sat Dec 12, 2015 12:11 am
by Csaba Nagy
Some recent pictures from Dissembling the BMCC.

First shown is the sensor assembly, showing the heat pipe / body cooling management.
Image

Next shows the Model number on the back of the Sensor. If there has ever been any doubt that the sensor is the CIS 2521F from Bae systems. This should eliminate any doubt.
Image

Last is shows the Dual stage peltier used in cooling the sensor. The specific type is unclear with no visible markings. It is a 30mm x30mm size.
Image

More to come.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Dec 24, 2015 8:10 am
by Csaba Nagy
So as I bet we all have noticed internal Battery on the Cinema Cameras isn’t very good, especially over time.

BMD states 90 mins, I can best around a little over an hour almost 3 years after. Which of course is not bad. The camera was designed to be powered off external batteries after all.
However it made me wonder If I could change or swap out the internal Battery for another pack of similar electrical characteristics.

My findings were quite revealing.

1st off the Cinema Camera uses a MinMax LP904086 Lipo Battery. It’s a 7.4v 3800mah Battery in a 2s1p configuration. http://www.minmaxenergy.com/newproductShow.asp?id=11

The battery uses a standard charging voltage of 8.4v (4.2v per cell) and cuts out at 6v (3v per cell)
This is great because it essentially uses a very standard voltage commonly associated with a 2 Series Battery Pack.

So with this I plan to upgrade the internal Battery to a custom made 7.4v 6800mah battery using 18650 Cells. Specifically the Panasonic NCR18650B, which is among the highest capacity 18650 you can buy at 3400mah per cell. http://industrial.panasonic.com/lecs/ww ... 0CE417.pdf

Next was determining the internal power consumption of the Cinema Camera. So I hooked up the internal battery connector to my bench power supply and this is what it looked like. ( pardon the crappy iPhone quality )



As you can see the power consumption steadily hovers at around ~15-16 watts. And what’s interesting is power usage actually slightly drops when recording as opposed to being idle. Not alot, but contrary to what one might believe.



The other thing I later tested is what happens to power usage with regards to the display backlight. From 100%-0% you see a drop of about 100ma. It’s not significant. So it will save you battery but not much.

The most intriguing part of this test was the fact the camera drops out at around 7.30v. Anything below that and the camera will just shut off when you try to record.
This is an issue because the internal battery and most batteries of that configuration have remaining power down to 5-6v (3-2.5v x2 )

So when the Cam battery is “dead” it in fact still has capacity and from my calculations this remaining capacity can be as high as 40%-50% of the batteries total capacity.

This is mind boggling to me and very much a Blackmagic design flaw.

So if we do the math here’s the theoretical run times of the camera with the internal and my proposed battery.

BMD Internal Battery
7.4v x 3800mah = 28.12wh
28.12wh / 16w = 1.76hr or 1h46m

Proposed Battery
7.4v x 6800mah = 50.32wh
50.32wh / 16w = 3.145hr or ~3h9m

The real world performance is obviously less and degrades from several factors including time, temperature and environment.

I put together a crude test battery pack that is 7.4v and 4800mah and it ran the camera for 2 1/2 hours.
Image

So there’s a look into how the Camera breathes. It’s less than perfect I’d say from these tests, but It works great as its designed for external batteries.

However It can be modified and used more practically in some situations with any external power.

More to come on that as await my shipment of new batteries.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Dec 24, 2015 9:17 am
by Anatoly Mashanov
I see no balance circuit on your 18650 cells. :o

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Dec 24, 2015 7:53 pm
by Csaba Nagy
Anatoly Mashanov wrote:I see no balance circuit on your 18650 cells. :o


You caught me! :o

No but I have a protection board on order, so while testing I just monitored voltages carefully to make sure nothing would drop too low.

But you almost don't need a protection circuit because as I stated the Camera powers down at around 7v which is still way above the safe over discharge voltage of most 18650. There is still a good amount of remaining capacity. So no worrying about over draining.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Sun Jan 03, 2016 11:48 pm
by Robert Niessner
Csaba, did you have a look at the power input connector of the BMCC? It often fails to recognize when external power is plugged in, maybe there is a weakness in the construction? Could that be improved somehow?

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu May 26, 2016 9:30 pm
by Csaba Nagy
Diggin this thread back from the grave, sorry guys... :) :lol:

Just thought I'd share an interesting observation I saw recently.

All BMD camera's are designed with a cooling system. The sensors contain a "refrigeration cooling system" which is done with a device called a peltier.

Simply put when powering a peltier heat gets moved from one side to the other. Making one side cold and the other hot. In order to maintain the cooling effect the heat must then be transferred away from peltier's hot side by using some kind of heatsink.

BMD's method of heat transfer for its early camera's use a flat cooling pipe from a company Amec Thermasol. This cooling pipe is made of MHP a material that by their testing significantly out performs copper.
Image

However for the first time I saw this image of a dissembled pocket with what appears to be a copper heat pipe.
Image

This makes me question a few things:
1. Were copper heat pipes used in early manufacturing runs?
2. Were copper heat pipes used later to address thermal issues?
3. Which actually performs better? By how much?

Just something that caught my eye and thought was interesting.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Apr 12, 2018 10:36 pm
by Chris Ross Leong
Csaba Nagy wrote:Diggin this thread back from the grave, sorry guys... :)

Just thought I'd share an interesting observation I saw recently.

All BMD camera's are designed with a cooling system. The sensors contain a "refrigeration cooling system" which is done with a device called a peltier.

Simply put when powering a peltier heat gets moved from one side to the other. Making one side cold and the other hot. In order to maintain the cooling effect the heat must then be transferred away from peltier's hot side by using some kind of heatsink.

BMD's method of heat transfer for its early camera's use a flat cooling pipe from a company Amec Thermasol. This cooling pipe is made of MHP a material that by their testing significantly out performs copper.
Image

However for the first time I saw this image of a dissembled pocket with what appears to be a copper heat pipe.
Image

This makes me question a few things:
1. Were copper heat pipes used in early manufacturing runs?
2. Were copper heat pipes used later to address thermal issues?
3. Which actually performs better? By how much?

Just something that caught my eye and thought was interesting.
Csaba, hello!
Yes it's been awhile but my BMCC is finally running out of internal battery juice. Needs replacing. How went your higher power cell conversion experiment, in the end?

Looking for a replacement for that Minimax LP904086 7.4v 3800mah 2s1p battery... Or better!

Best
Chris


Sent from my Nexus 7 using Tapatalk

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Fri Apr 13, 2018 1:47 am
by Anatoly Mashanov
Chris Ross Leong wrote:it's been awhile but my BMCC is finally running out of internal battery juice. Needs replacing. How went your higher power cell conversion experiment, in the end?

It looks that the Li Ion batteries have a memory effect. Remove the batteries and slowly discharge them to 3.0 volts per cell. You may need to discharge them separately. Then charge them back to 4.2v. Do not discharge below 3.0v or charge above 4.2v. If their voltage differs then you again may need to charge them separately. Repeat 2-3 times. Every operation with Li ion batteries is dangerous, you have been warned.

I've recently did this with Fitel S-121 battery which has been discharged to zero. It was necessary to disassemble the battery pack and charge the cells bypassing the controller, then do 3-4 cycles. Now the battery keeps enough juice for at least 2-3 splices. The new battery costs more than I paid for all the splicer with battery and a set of eliminators.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Sun Jul 29, 2018 3:46 am
by Mark Georgeff
JULY 28 2018

Similar problem with PRO BATTERY pack charging my BMCC 2.5 K
Have not used camera in a good 2 years...charged PRO battery the other night...was able to shoot for less than an hour.
Don't believe I had the camera on all night long and wore internal battery out.
Maybe I did.
Recharging it again now.
Can't recall about the internal battery if even there is one.
Looking for the manual online now...
Any hints to what direction for me to research?
Thanks.

MARK GEORGEFF

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Jan 24, 2019 5:11 am
by Wayne Steven
Csaba Nagy wrote:Diggin this thread back from the grave, sorry guys... :) :lol:

Just thought I'd share an interesting observation I saw recently.

All BMD camera's are designed with a cooling system. The sensors contain a "refrigeration cooling system" which is done with a device called a peltier.

Simply put when powering a peltier heat gets moved from one side to the other. Making one side cold and the other hot. In order to maintain the cooling effect the heat must then be transferred away from peltier's hot side by using some kind of heatsink.

BMD's method of heat transfer for its early camera's use a flat cooling pipe from a company Amec Thermasol. This cooling pipe is made of MHP a material that by their testing significantly out performs copper.
Image

However for the first time I saw this image of a dissembled pocket with what appears to be a copper heat pipe.
Image

This makes me question a few things:
1. Were copper heat pipes used in early manufacturing runs?
2. Were copper heat pipes used later to address thermal issues?
3. Which actually performs better? By how much?

Just something that caught my eye and thought was interesting.


Csaba, do you have serial number or year of each, that might be an indicator to which BM thought was better?

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Jan 24, 2019 9:49 am
by Wayne Steven
They were very inefficient, and so generated significant heat of their own. The pictures inside the case reveal less surface area to pick up heat. Microstructuring heat sink elements in the enclosure mold would probably significantly improve heating issues. But a fluid thermal unit feeding from top of the cooler to something stuck inside the case, might have helped. Preserving the existing cooler in order to pump heat to the second stage, but you could have the solid state unit between the fluid unit and the case instead. However, modeling/testing needed to find which is best. But, really more worth doing when the 8k+ pocket comes out.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Jan 24, 2019 9:56 am
by lee4ever
Csaba, do you have serial number...


the second image with the copper is from here:



See:

Image

SN: 1098003 ?

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Jan 24, 2019 11:34 am
by Wayne Steven
You know, that seems a poor way to conduct heat away from the sensor. That area the thermal heatsink is attached to by thermal paste is in an enclosed area (maybe to stop the sun from getting to it too much under the skin. Is there some structure in the enclosure at that area, to conduct heat away from the heat sink? Also, what is the black skin made out of. If it is not thermally conductive enough, it could hinder cooling, and attract heat when the sun hits it.

If all the answers are bad above, then testing it without the black skin, or substituting a white silica skin in parts which need to be handled, for grip, might be worth a look at. A miniature long heat sink and/or fan in the soit opposite where the heat fin attaches to the case might help.

But let's step back, again. If the sensor is 0.8 watts max, and maybe a lot less at 30p, and the screen is 0.2 watts, where's the rest of the something like 29 watts reported going? That's the enemy here. Having that much producing heat floating around trapped in the enclosure. Would a micro heat sink structure attached to the outside of a bare case be enough, or b) stick to the inside as well, or c) with fan as well pushing internal air onto it, D) a fan in the outside of the heat exchanger as well?

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Wed Aug 28, 2019 8:36 pm
by Henchman
Csaba Nagy wrote:So as I bet we all have noticed internal Battery on the Cinema Cameras isn’t very good, especially over time.

BMD states 90 mins, I can best around a little over an hour almost 3 years after. Which of course is not bad. The camera was designed to be powered off external batteries after all.
However it made me wonder If I could change or swap out the internal Battery for another pack of similar electrical characteristics.

My findings were quite revealing.

1st off the Cinema Camera uses a MinMax LP904086 Lipo Battery. It’s a 7.4v 3800mah Battery in a 2s1p configuration. http://www.minmaxenergy.com/newproductShow.asp?id=11

The battery uses a standard charging voltage of 8.4v (4.2v per cell) and cuts out at 6v (3v per cell)
This is great because it essentially uses a very standard voltage commonly associated with a 2 Series Battery Pack.

So with this I plan to upgrade the internal Battery to a custom made 7.4v 6800mah battery using 18650 Cells. Specifically the Panasonic NCR18650B, which is among the highest capacity 18650 you can buy at 3400mah per cell. http://industrial.panasonic.com/lecs/ww ... 0CE417.pdf

Next was determining the internal power consumption of the Cinema Camera. So I hooked up the internal battery connector to my bench power supply and this is what it looked like. ( pardon the crappy iPhone quality )



As you can see the power consumption steadily hovers at around ~15-16 watts. And what’s interesting is power usage actually slightly drops when recording as opposed to being idle. Not alot, but contrary to what one might believe.



The other thing I later tested is what happens to power usage with regards to the display backlight. From 100%-0% you see a drop of about 100ma. It’s not significant. So it will save you battery but not much.

The most intriguing part of this test was the fact the camera drops out at around 7.30v. Anything below that and the camera will just shut off when you try to record.
This is an issue because the internal battery and most batteries of that configuration have remaining power down to 5-6v (3-2.5v x2 )

So when the Cam battery is “dead” it in fact still has capacity and from my calculations this remaining capacity can be as high as 40%-50% of the batteries total capacity.

This is mind boggling to me and very much a Blackmagic design flaw.

So if we do the math here’s the theoretical run times of the camera with the internal and my proposed battery.

BMD Internal Battery
7.4v x 3800mah = 28.12wh
28.12wh / 16w = 1.76hr or 1h46m

Proposed Battery
7.4v x 6800mah = 50.32wh
50.32wh / 16w = 3.145hr or ~3h9m

The real world performance is obviously less and degrades from several factors including time, temperature and environment.

I put together a crude test battery pack that is 7.4v and 4800mah and it ran the camera for 2 1/2 hours.
Image

So there’s a look into how the Camera breathes. It’s less than perfect I’d say from these tests, but It works great as its designed for external batteries.

However It can be modified and used more practically in some situations with any external power.

More to come on that as await my shipment of new batteries.



How did this end up.
I just picks up a Bmpc 4k with a completely dead battery for $600

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Wed Aug 28, 2019 9:16 pm
by Csaba Nagy
Henchman wrote:How did this end up.
I just picks up a Bmpc 4k with a completely dead battery for $600


Put a 2S protection circuit between the lithium cells and the camera and yea it should work just fine. I couldn't find a way to fit 4x 18650 so If you use some larger 21700 instead and just use two in series it should give you some nice capacity.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Aug 29, 2019 4:31 am
by Henchman
Csaba Nagy wrote:
Henchman wrote:How did this end up.
I just picks up a Bmpc 4k with a completely dead battery for $600


Put a 2S protection circuit between the lithium cells and the camera and yea it should work just fine. I couldn't find a way to fit 4x 18650 so If you use some larger 21700 instead and just use two in series it should give you some nice capacity.

So, 2 of these?
I have to admit, I don't know what a "2S protection circuit " is.

https://www.imrbatteries.com/samsung-40 ... MkQAvD_BwE

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Aug 29, 2019 11:02 am
by Wayne Steven
It would be great if BM made a 6k programmable sensor module, people could hook up POV, or make a camera out of. The choices in machine vision and security are limited. A Thunderbolt optical line could go a long distance, and maybe even extended to take multiple TB traffic lines. Go of for studios, but also good for very high uncompressed data rates high end 32mp+ 16 bit+ for machine vision. Plenty of reasons to do it, even casino security cameras for bigger money.

Re: Dissecting Blackmagic

PostPosted: Thu Aug 29, 2019 11:33 am
by pulalis
Csaba Nagy wrote:Some recent pictures from Dissembling the BMCC.

First shown is the sensor assembly, showing the heat pipe / body cooling management.
Image

Next shows the Model number on the back of the Sensor. If there has ever been any doubt that the sensor is the CIS 2521F from Bae systems. This should eliminate any doubt.
Image

Last is shows the Dual stage peltier used in cooling the sensor. The specific type is unclear with no visible markings. It is a 30mm x30mm size.
Image

More to come.



The sensor (CIS 2521F) you mentioned supports up to 100 fps.
It would be great if blackmagic gave us higher frame rates.
Because this camera is very good.

https://datasheets.globalspec.com/ds/25 ... 0C85218E40

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Aug 29, 2019 12:57 pm
by Sean van Berlo
Framerate is not just sensor dependent, it's also dependent on processing power and the ability to deal with the additional power and heat needed for these higher framerates.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Thu Aug 29, 2019 4:58 pm
by lee4ever
That's it. We can test that, but BMD is supposed to release new firmware with 48, 50 or 60 fps for BMCC, BMPCC and I'm sure there won't be any problems with the processing power.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Fri Aug 30, 2019 12:18 am
by Wayne Steven
Lee, where does it say they are planing to release higher frame rate versions of the firmware?

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Fri Aug 30, 2019 12:22 am
by Wayne Steven
In matter of fact, where is that video where an BM engineer explains why they can't increase the frame rate that much on the old pocket? Nobody has been able to point me to it? Was it deleted.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Fri Aug 30, 2019 2:57 pm
by lee4ever
BMD didn't mention anywhere that they are planning a firmware with more FPS, but in order to refute the stubborn assertion that the BMCC, BMPCC supposedly doesn't deliver enough performance, BMD should simply release a firmware with 48, 50 or 60 fps so we can test it. That the FPGA chip and the HDMI chip (at least I know the specs from BMPCC) can't do more than 30fps is simply a false widespread claim.

Those who claim this should better inform themselves about the FPGA. That is not the problem.
The soldered HDMI chip can do more than 30fps, so no problem.
Fairchild CMOS sensor can also do more than 30 fps, so no problem.

The problem is a missing firmware.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Fri Aug 30, 2019 3:15 pm
by Wayne Steven
OK. But I didn't read it that way. But you have a point. If the HDMI chip can deliver 1080p50/60 then that can go straight to an external recorder with little FPGA processing. Which is a good thought Lee. They could even put Bayer over HDMI, and as that is wide known now, not like when I kicked off the idea last decade, maybe people will accept it is possible without getting up in arms offensively and trolling. However, I haven't heard from you, so I guess you aren't working in your project anymore.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Fri Aug 30, 2019 3:22 pm
by Wayne Steven
Actually, off topic a bit. The zcam E1 could have done with the HDMI stuff. They just didn't seem to much. The sensor in there might have been better than claimed to, from what I learned about false reporting dynamic range. I knew a guy that did packages which normalised footage for grading. I was surprised at how well he could bring the sunlit sky up on the claimed DR, but his measurements mapping must have brought compressed stops out. I should see what he has for the pockets.

It's definitely worth exploring these old cameras to see how much extra you can bring out.

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Sat Aug 31, 2019 12:26 am
by lee4ever
However, I haven't heard from you, so I guess you aren't working in your project anymore.


It is possible to read, but nothing can be written. But I won't give up. :D

Re: Dissecting Blackmagic | Hardware Discussion

PostPosted: Sat Aug 31, 2019 1:39 am
by Wayne Steven
OK :)

Did you learn how to change setting parameters?