SDI burnout/rolling noise issue BMCC 2.5k EF

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alexsiliato

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SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue May 20, 2014 2:12 pm

So I'm at the end of my rope here guys.

I'm on my FOURTH Blackmagic Camera 2.5k EF in less then a year. It's just about out of it's warranty as well. I've sent it back numerous times to fix the "Rolling Lines" I see at the camera's "native" 800 iso. It's on all my footage, always has been. I've learn to shoot with it and avoid it as best I can but this morning when I noticed I lost my SDI port I figured I'd ask everyone else how their cinema camera's are doing.

Is it worth it to even get the SDI port repaired? After all it WILL most likely just burn out again. Of course while doing some research I read a vague, ominous warning from "Eddie". I'll just suck it up that my $600 Lilliput 665 no longer works nor does the BMCC SDI port.

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LoganStewartDP

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Re: SDI/rolling noise issue BMCC 2.5k EF

PostTue May 20, 2014 2:53 pm

Which repair hub are you sending it to? Had to send mine in then again to get the proper pcb board that didn't roll but they were more than helpful and quick.
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Eugene Carter

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Re: SDI/rolling noise issue BMCC 2.5k EF

PostTue May 20, 2014 3:08 pm

The SDI issue is one of my main concerns with my BMCC. I feel like I have a ticking time bomb and I think I'm getting rid of it for a GH4 before the SDI blows out. I haven't even attached a monitor to the BMCC I currently have (also my fourth), for fear that it will blow out. I keep hearing stories about the SDI blowing out. This paired with the delay in fixing the in camera audio and orange reds, has me ready to give up.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue May 20, 2014 4:37 pm

Just wanted to mention that the SDI port of my BMCC is doing fine since February 2013, when I received the camera. I am using the SmallHD AC-7 SDI as the preview monitor.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue May 20, 2014 7:26 pm

probably not much comfort... my bmcc mft has been using liliput 663s sdi monitor with no issues.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue May 20, 2014 10:16 pm

And moderators deleted my photos.
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Doge

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed May 21, 2014 3:59 am

We are currently on our 5th BMCC due to a blown SDI port. They have replaced it every time, but the one year warranty is nearing it's end. After it blows outside of it's warranty, it will become an almost useless piece of equipment in our workflow. Connecting to a Marshall V-LCD70MD-3G.

I asked tech support if this was a common issue and was told that it is "very uncommon". I'm inclined not to believe that. That or we have extremely bad luck.

How disappointing.
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alexsiliato

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed May 21, 2014 6:12 pm

Doge, were you using an external battery pinch or v mount plate? Or any other accessories plugged in to the camera?
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed May 21, 2014 10:14 pm

Yes, we use a Tilta Rig with a V-Mount battery solution.
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Ryan McCarvill

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed May 21, 2014 10:23 pm

Doge wrote:We are currently on our 5th BMCC due to a blown SDI port. They have replaced it every time, but the one year warranty is nearing it's end. After it blows outside of it's warranty, it will become an almost useless piece of equipment in our workflow. Connecting to a Marshall V-LCD70MD-3G.

I asked tech support if this was a common issue and was told that it is "very uncommon". I'm inclined not to believe that. That or we have extremely bad luck.

How disappointing.


Don't know about where you live but here in NZ a 12 month warranty is really just them trying to blow you off.

The consumer guarantees act specifies that something should last a reasonable period of time, and based on previous cameras I would expect my bmcc to last ten years of moderate use. I've had a refrigerator replaced six years after its official warranty ran out because of the consumer guarantees act. Likewise handles in my kitc hen, basically the manufacturers warranty is a cop out and they have no legal ability to limit your warranty period to twelve months.

Also when you received the replacement camera would reset the warranty period if that replacement camera was new.

So it might be worth looking at your consumer laws as you might be more protected than you think.

EDIT: Weird that K I T C H E N is asterisked out, is kitchen some sort of weird swear word that I don't know about?
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostFri May 23, 2014 2:01 am

Ryan McCarvill wrote:
Doge wrote:We are currently on our 5th BMCC due to a blown SDI port. They have replaced it every time, but the one year warranty is nearing it's end. After it blows outside of it's warranty, it will become an almost useless piece of equipment in our workflow. Connecting to a Marshall V-LCD70MD-3G.

I asked tech support if this was a common issue and was told that it is "very uncommon". I'm inclined not to believe that. That or we have extremely bad luck.

How disappointing.


Don't know about where you live but here in NZ a 12 month warranty is really just them trying to blow you off.

The consumer guarantees act specifies that something should last a reasonable period of time, and based on previous cameras I would expect my bmcc to last ten years of moderate use. I've had a refrigerator replaced six years after its official warranty ran out because of the consumer guarantees act. Likewise handles in my kitc hen, basically the manufacturers warranty is a cop out and they have no legal ability to limit your warranty period to twelve months.

Also when you received the replacement camera would reset the warranty period if that replacement camera was new.

So it might be worth looking at your consumer laws as you might be more protected than you think.

EDIT: Weird that K I T C H E N is asterisked out, is ******* some sort of weird swear word that I don't know about?



Good to know, I'll have to look into the laws here in the US. That word was being targeted by spam bots flooding the forum.
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BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 4:55 pm

I'm actually scared to hook up my external monitor to the BMCC because there are so many reports of the SDI port blowing out. I'm thinking about selling the camera and moving on to another company, but I don't want this thing to blow out before I sell it. There is obviously an issue here and the right thing to do would be to recall the BMCC and issue a permanent fix for this issue.
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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 4:59 pm

Where are these reports? I would like to see them and see what other users have to say.

I've been using my camera with a SmallHD monitor for over a year and I'm not getting this issue and I use it a lot. I just finished a feature on it, shooting all day with the SDI monitor on, and no issues at all.
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Eugene Carter

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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 5:02 pm

See this thread:
viewtopic.php?f=2&t=22659

There are many more on other forums, but I think it's against the rules to post them. I'm sure there are more reports of the issue on here as well.
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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 5:17 pm

I haven't had the issue myself and have used the SDI port on every shoot but there are an awful lot of reports of the failure.

I wonder if the power source is the same for both the BMCC and the effected monitor in the instance if SDI blowout. There was a recent thread describing some kind if order that's needed to ensure power is sent properly.
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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 5:38 pm

I haven't had the issue and I've used the SDI ports on my cameras a lot... pretty much every shoot. I've mostly only ever connected my cams to other BMD hardware, namely their Hyperdeck Shuttles(II) and their HDLink 3D (for LUT conversion). The one exception is I sometimes use a Convergent design NanoFlash for recording long stuff, but that's very rare (probably twice in a year). My point is, I've never had issues.
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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 7:48 pm

Aaron Scheiner wrote:I haven't had the issue and I've used the SDI ports on my cameras a lot... pretty much every shoot.


same here, over a year now, and no such isues
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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSat May 24, 2014 10:39 pm

So... two people post something about it in another thread from 4 dyas ago and you decided to make a new thread?

I've had no issues with my Ikan VX7 or my EVF.
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Re: BMD Needs to Issue a Recall on the BMCC SDI Port

PostSun May 25, 2014 2:35 am

To protect my gear, the practice has been to make sure everything is off first and then power up when all devices are connected.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostSun May 25, 2014 3:42 pm

rockroadpix wrote:So... two people post something about it in another thread from 4 dyas ago and you decided to make a new thread?

I've had no issues with my Ikan VX7 or my EVF.


Original posting also included other issues that blackmagic took down off the forum.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostSun May 25, 2014 3:43 pm

Doge wrote:Yes, we use a Tilta Rig with a V-Mount battery solution.


I use the Tilta V-plate as well. It's possible the different voltages from the plate caused the blowout.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Jun 02, 2014 5:31 am

I believe that I am one of the unfortunate experiencing SDI failure with the BMCC :cry: I have been using with the SmallHD DP7 HB for 2+ months without issue. Suddenly yesterday on a professional shoot, it was working first half, and then I switched my rig out and no signal. I was also using the Tilta V-plate at the time...
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Jun 02, 2014 7:58 am

Seems the Tilta V-Plate could be the reason...

I also had two times a blown out sdi-port on my bmcc-ef :
first time only the bmcc was affected, second time also the sdi-in of my Marshall-Display got burned.

Both times i had the Tilta V-Plate attached...
:-(
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sean mclennan

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Jun 02, 2014 2:52 pm

I'm worried mine is about to die...1 month after my warranty expired :\

Used my BMCC EF on a 24hr film challenge Friday night, with an Alphatron EVF...3 hrs in, the Alphatron lost the signal from the BMCC. Happened again the next morning when shooting resumed. (again after a few hours of constant operation)

Can't be sure it's the BMCC and not the Alphatron...but the EVF was still functioning and the menus worked, etc...it just said "no signal".

I'm really hoping my SDI port doesn't die :cry:
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Jun 02, 2014 5:20 pm

See what I'm saying?

I love the image on my BMCC, but the reliability issue is always in the back of my mind. Seriously think I'm going to ditch it for a GH4 + Ninja 2 before something blows out on it.

sean mclennan wrote:I'm worried mine is about to die...1 month after my warranty expired :\

Used my BMCC EF on a 24hr film challenge Friday night, with an Alphatron EVF...3 hrs in, the Alphatron lost the signal from the BMCC. Happened again the next morning when shooting resumed. (again after a few hours of constant operation)

Can't be sure it's the BMCC and not the Alphatron...but the EVF was still functioning and the menus worked, etc...it just said "no signal".

I'm really hoping my SDI port doesn't die :cry:



Were you using the Tilta plate? I made a post requesting a recall, but it got lumped in with the other threads. Really, the BMCC is like a throw away camera, with a beautiful image. Like they say, if you want reliability out of BMD stuff, buy 2 when you need 1 and buy 4 when you need 2.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Jun 02, 2014 8:13 pm

Eugene C. wrote:See what I'm saying?

I love the image on my BMCC, but the reliability issue is always in the back of my mind. Seriously think I'm going to ditch it for a GH4 + Ninja 2 before something blows out on it.

sean mclennan wrote:I'm worried mine is about to die...1 month after my warranty expired :\

Used my BMCC EF on a 24hr film challenge Friday night, with an Alphatron EVF...3 hrs in, the Alphatron lost the signal from the BMCC. Happened again the next morning when shooting resumed. (again after a few hours of constant operation)

Can't be sure it's the BMCC and not the Alphatron...but the EVF was still functioning and the menus worked, etc...it just said "no signal".

I'm really hoping my SDI port doesn't die :cry:



Were you using the Tilta plate? I made a post requesting a recall, but it got lumped in with the other threads. Really, the BMCC is like a throw away camera, with a beautiful image. Like they say, if you want reliability out of BMD stuff, buy 2 when you need 1 and buy 4 when you need 2.


I have the Tilta plate but I was running on AC. The Tilta plate was powering the Alphatron and my mixer.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Jun 02, 2014 8:39 pm

^Good luck, hope everything works out.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 5:33 pm

Just bought a dp7-pro planning to power off of the same Switchtronix v-mount battery as the BMCC. Has anyone else had the BMCC's sdi blowout while sharing a battery source on the Switchtronix pro-x gps or has it been specific to the tilta plate?
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 6:38 pm

I just blown my SDI yesterday, just after reading this thread :cry:

Call it bad karma!
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 6:40 pm

Seems the tilta plate could be contributing in some way. I hope mine doesn't go.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 7:05 pm

frle was your monitor's sdi damaged in the burnout too?
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 9:04 pm

woodybrando wrote:frle was your monitor's sdi damaged in the burnout too?

The monitor was patched through SDI->HDMI converted and it died also. I don't know what was the cause, converter or bmcc... but fortunately the monitor survived. Yeah lucky me! :cry:
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 9:45 pm

that's a good point I wonder if the sdi to hdmi converters are causing problems. I've been using a hdmi to sdi pass through converter for the last six months or so and so far no problems other than that monitors that can't accept 24p signal won't work. Did your convert convert the signal too to be able to work on 60hz only monitors?
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 10:02 pm

I haven't had any problems till now. I was using this setup for almost a year. But yesterday, the monitor flicked like the cable was losing connection... and then PUUFF... everything went black - NO SIGNAL

My converter is/was just a pass through connected to Lilliput 5D-ii/O/P monitor.
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Eugene Carter

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Jun 03, 2014 10:36 pm

All arrows point to the BMCC being that many different setups have ended up fried. There is obviously a problem with that port.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed Jun 04, 2014 5:24 am

I have two BMCC's, one I returned for rolling noise, and they fixed it. Working fine now... No problems with SDI so far...


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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostThu Jun 05, 2014 8:25 pm

I appear to also be suffering from this SDI burnout issue, really rather irksome since I've not used the SDI out on this particular camera up until now. The one on my first BMCC (EF) worked fine, but my new one (MFT)? Nada. More details:

viewtopic.php?f=2&t=23230
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostSun Aug 17, 2014 10:57 pm

FINALLY!

After much testing today I found that the blackmagic cinema camera has a ground loop issue in the design.

Here are some photos, sorry about the size. My camera's mounted on a steadicam with an SDI monitor.
I used an BNC to RCA adapter just to get a good reading.
Image
Image
Image

The ground back-feeds into the SDI port. Here are photos of me testing the SDI port with a multimeter and getting a reading of about 5v from the sdi port itself.

The TILTA plate functions as it should until you connect to the camera in which the poor ground will overide the accessory switch. I will be sending my camera back for a new PCB board and now using a ground loop eliminator.
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Nikolay Smirnov

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Aug 18, 2014 6:24 am

how can I make that test?
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Aug 18, 2014 8:38 am

alexsiliato wrote:FINALLY!

After much testing today I found that the blackmagic cinema camera has a ground loop issue in the design.

Here are some photos, sorry about the size. My camera's mounted on a steadicam with an SDI monitor.
I used an BNC to RCA adapter just to get a good reading.
Image
Image
Image

The ground back-feeds into the SDI port. Here are photos of me testing the SDI port with a multimeter and getting a reading of about 5v from the sdi port itself.

The TILTA plate functions as it should until you connect to the camera in which the poor ground will overide the accessory switch. I will be sending my camera back for a new PCB board and now using a ground loop eliminator.


Alex

thank you for taking the time to do the test, and Im glad you found something since this issue was bothering me a lot ,

but can you please explain it to us (non technical people :D )
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Aug 18, 2014 2:35 pm

BlackMagic Support should clarify the inssue and accept it. If in a few years the vast majority of users do this happens, the company would notice in their sales.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Aug 18, 2014 2:43 pm

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Aug 18, 2014 2:45 pm

Actually I see the test isn't potentially clear. You should measure the SDI output without external battery first. Then with battery charging the camera. It actually could be the plate which is causing the problem.

As long as I know anything above 0.1 volts output in SDI feed is really bad.
Last edited by Nikolay Smirnov on Mon Aug 18, 2014 4:22 pm, edited 1 time in total.
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostMon Aug 18, 2014 3:55 pm

I've done much further testing then what I've shown, I will be posting more results today or tomorrow
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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostTue Aug 19, 2014 3:19 am

alexsiliato wrote:Here are photos of me testing the SDI port with a multimeter and getting a reading of about 5v from the sdi port itself.


FWIW

I would expect that when metering across the SDI with a DC VOM that you should get 0 volts DC.
AFAIK the SDI (serial digital interface) is an 800 millivolt peak-to-peak HF digital signal.
So you would require a scope to see it as most consumer VOM's won't measure up to its frequency.
At most you may see a very few mV depending on your VOM.

The SDI Out BNC connector shell/shield appears to be connected to the camera's common ground, which includes the camera case, DC Power Input ground, Thunderbolt port shield, USB port shield, etc.
The TRS Audio Inputs do appear to have isolated sleeves however. Probably to prevent audio ground loops.

I would suspect that if your SDI is reading 5V across the BNC connector when the camera is connected to your external battery plate, and nothing is connected to the SDI, that there is something odd going on.
When I connect either the BM AC charger or an external DC battery pack to the camera, I do not read 5V DC on the SDI connector.

When the camera is connected to an external battery source, if you were to read a voltage differential between the SDI connector's shell/shield and the battery pack's ground, then I would suspect a broken ground connection on the SDI BNC, and possible issues.
However, that is only speculation as I have neither disassembled my BMCC or seen the schematics.
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Andrew Boal

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed Aug 20, 2014 2:23 am

So would something like this help protect the SDI port?

http://www.doss.com.au/gli02-video-grou ... -isolator/

I can get one of these for about $20 on ebay (or even $10 from overseas), which is at worst case a $20 sdi cable and at best case saving a whole lot of problems during a shoot.
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David Green

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed Aug 20, 2014 3:26 am

No, it won't.


I spent half an hour looking online for any V-mount plate schematics to no avail.
I don't plan on spending the money on a Tilta just to break it open and see how they are splitting and regulating the various voltages.
If they are using a DC-DC converter and regulators, with independent output tap grounds, that is probably the issue.
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Mubarak Almubarak

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed Aug 20, 2014 3:50 am

@David Green,

Someone opened it up and posted few pictures of it in another thread
viewtopic.php?t=23348

Post #18 (I think)
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David Green

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed Aug 20, 2014 5:18 am

Thanks Mubarak.
I had a quick look at the post at that link.
I also had a closer look at the photos posted above.

Although the photo of the PCB was small and blurry, and it would have been helpful to see both sides of the board, it looks like a basic DC-DC convertor/regulator for each of the plate's barrel type power connectors, and each connector looks like independent floating negatives (or grounds FAIAP). I can't tell 100% for certain without seeing better photographs or handling one of them in person.

The D-Tap connector is connected directly to the battery terminals, so it will also have a different negative potential than the rest of the barrel power connectors.

The floating grounds will be for safety reasons and to allow for isolation between devices powered by the plate, however, that means that there will be a chance of problems caused by voltage potential drift if two devices are connected to individual power connectors AND also have an additional cable between them.
For example, with an EVF setup, where the camera is on one plate power connector, the EVF is on a second plate power connector, and an SDI cable is connected between the devices.
You should also be able to read random voltage differences between the device's SDI connector shells when the connecting SDI cable is removed.

I'm willing to bet that this issue isn't just a BMC plus Tilta plate issue.
That plate design when also used on any other camera, such as a Canon C100, C300, etc., along with an EVF connected to a second voltage power connection on the plate, is going to have the same frying problem.

If I had one of these plates, other than making some serious modifications to it or throwing it away, I would only use it with a camera and EVF setup if both the camera and the EVF were powered from the exact same plate power connector.
For example, plugging a D-Tap multi-tap into the plate D-Tap connector, then D-Tap cables from the multi-tap over to the camera and EVF. That way they are using a common negative connection, with no chance for floating voltage potential variations.

When used on a setup such as the plate's D-Tap to the BMC and one of the other plate power connectors to a mic preamp, there probably won't be any issues since the BMC uses isolated ground connections on the 1/4" TRS connectors.
Although, IMHO any voltage potential swings will still be hard on the equipment components, and I wouldn't do it.

IMHO, anyone who is using this plate, or any plate that is using the same design of independent floating negatives, should never connect any two devices to two different plate power connectors when there is also an additional cable between the devices.
If a device is going to be cabled to any of the camera's inputs or outputs, then that device should also be ran from the same plate power connector as the camera.
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Joaquin Torrents

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Re: SDI burnout/rolling noise issue BMCC 2.5k EF

PostWed Aug 20, 2014 12:17 pm

Thanks a lot, David, for your useful and detailed explanation of the problem.
Joaquin Torrents
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