The SDI issues

[Björn Benckert]

Do we need to unplug SDI even if we are changing the battery on the monitor only?

What about swapping out a BP-9 on the back of the Komodo. eg replacing a depleted battery while the other battery continues to power the camera?

Not sure. It sound crazy if every time power is removed or added video cables have to be unplugged... But that is as I understand what all manufacturers are claiming now, but I hope I´m wrong as it sounds nuts.

Again I unplug batteries and cables all the time with our without power and don't think much about it. So maybe I´m just been lucky but yes, who have time for such precautions. I´m more worried the SDI connector would be worn out from all the unplugging.

 

[Robert Hofmeyr]

Seems mad to me. According to Red's manual, swapping a battery on the rear of the camera requires that you shut down then disconnect the SDI cable then replace the battery then reconnect the SDI then boot the camera. I hope someone from Red chimes in here to clarify.

 

[Massimiliano_Serra]

For what I know the sdi cable must not be plugged in if you place or remove a battery not when you turn on/off camera and monitor.

Mount batteries, plug SDI, turn on.

Turn off, unplug SDI, remove batteries.

If you only need to turn on/off without removing batteries, SDI cable can stay plugged in.

 

[Robert Hofmeyr]

If the problem is connecting the +ve before the ground, thus causing the ground to loop via the monitor to the SDI, then there surely can't be any issue if the monitor is powered by it's own battery? Even if the monitor is powered from the camera or via d-tap, I can't see how the loop could be completed when attaching/removing batteries. The only case I can see where there might be an issue is when plugging in/out the monitor's power cable when the monitor and camera share the same power source.

 

[Leonard Frederic Caspari]

But my friend just had a Komodo here in Stockholm fried this way...

Any information on components and third party accessories that he used? I remember having accessories and cables fried by bad wiring on a Tilta V-Mount plate many years ago while having camera, recorder and EVF hooked up to one another and powering them through D-Tap. (I'm sure their wiring has improved in the meantime). This was on a C100. So none of the 6G/12G SDI related issues could have been the problem back then, but a wrong ground loop for sure. Been using regulated adapters ever since. So that if something fries it's "only" the relative cheap cable that needs to be replaced.

Not pointing fingers, but it would be interesting to know the components and accessories that were used when the SDI port died. The fact that this issue is reported more often with the Komodo could also be due to cheaper third party accessories that are being used alongside the camera.

 

[Vance Colvig]

What I do not understand is if there is an opportunity to fry the SDI board through the BNC connector, it seems that the outer barrel is floating and not properly bonded to the chassis or camera body if the body is also bonded to the battery negative. Voltage surges can be handled by semiconductors and is common in electronic design*. Overvoltage beyond stated values per manufacturer is another story and can cause serious damage. This should not occur however with recommended camera batteries per operating manuals.

Lightning strikes, exposure to extreme high voltages such as Tesla coils,and static electricity discharges are the exceptions.

 

[Bill Ravens]

Gonna jump in here because a lot of this is innuendo or unsubstantiated theory. It would be good to have more factual feedback from Red, because even my following logic is no more than innuendo.
At any rate, the fact seems to be related to the negative pole of a D-tap plug making contact before the positive pole, causing a ground loop. For that matter, a ground loop would be a static discharge thru any negative side of the circuitry that is neither grounded nor disconnected by switching off.
1-ground loops are built up static charge that are not adequately grounded.
2-if the D-tap plug is already installed, complete connection, i.e. both poles are already in contact with the power source, a ground loop is unlikely.
3-if the D-tap is plugged in and the battery is removed/installed, can a similar ground loop happen if the negative pole makes contact before the positive pole?
4-turning the camera off/on should not affect anything unless the on/off switch is poorly designed such that the ground circuit is never disconnected from the power source.

 

[Mike P.]

Yeah, but not everyone is using Dtap to power their monitors on Komodo (I would've thought the majority are using on-board monitor batteries).

DSMC1 had SDI and HDMI boards burn out, which I thought was ultimately why I/O was moved to a module in DSMC2. In retrospect it may have been the SDI-short issue. Further, 1G~3G (of DSMC1 and 2) are supposed to be *less* susceptible than 6G~12G (carrying 4k), so maybe that's why Komodo seems more sensitive.

I too am very disappointed with the lack of clarity (re: camera battery and/or SDI accessory battery replacement throughout the day requiring a mini-tear down procedure). My plan/hope, was to use a 2pin-lemo-to-accessory cable, so the only battery that would be removed would be the camera battery. Logic being that because it's the one battery, after it's all connected it wouldn't be possible that the +ve sleeve would hit first... But like everyone here, I'm not confident that'll prevent the problem on battery swaps if leaving the SDI connected.

Worse still, what if you're hot-swapping to keep the camera up? Everything would remain powered, but would replacing the dead battery with a fresh one potentially cause the +ve to hit first and short your SDI? (maybe that's exactly what's happening with Komodo; people swapping one of the BPs while the camera is still powered up and SDI connected.)

Things are just as grey when using SDI for live/studio work; if you're using AC on the camera and you have a long SDI run to a switcher, does the switcher need to be connected to AC but powered off before connecting the SDI to camera? If so, wtf?

Regardless of the answers, anyone who's been on set sees how nonchalantly those connectors and batteries are attached/disconnected/powered with video village. It's wild. Add in booting up the camera early for warm-up or black shade or to avoid a ~30sec boot-time, and it's absolutely unrealistic to expect a working set to follow that order with power-downs/disconnections on monitor battery swaps... Only the Owner-Ops who baby their equipment would be able to even attempt it; if it's a rental, no one would give a crap.

Whoddathought HDMI would be a more bulletproof connection. LOL.

 

[Siddhu S.]

Do we need to unplug SDI even if we are changing the battery on the monitor only?

What about swapping out a BP-9 on the back of the Komodo. eg replacing a depleted battery while the other battery continues to power the camera?

THIS!

I’ve been sleepless over these exact 2 questions!

 

[Andreas F. Scheucher]

I did not noticed this until now. So we all need a statement from RED about the procedures for Powering ON the Komodo and the Monitor with plugged batteries and plugged SDI cable.(or not) And when we do hotswapping the batteries om the komodo, is it necessary to unplu the sdi cable ?

 

[Jimmy Scanlon]

At what point does RED jump in or get notified? :banghead:

 

[Vance Colvig]

Page 141 in the latest operation manual for the Komodo states:

WARNING: Always attach the power or batteries before attaching the SDI BNC cable. Always remove the SDI BNC
cable before removing the power or batteries.

Maybe that is the reason Red has not responded to this thread.

 

[Robert Hofmeyr]

Page 141 in the latest operation manual for the Komodo states:

WARNING: Always attach the power or batteries before attaching the SDI BNC cable. Always remove the SDI BNC
cable before removing the power or batteries.

Maybe that is the reason Red has not responded to this thread.

I think I and others are looking for a bit more clarity on this warning. Does it include dedicated monitor batteries, or just batteries that power the camera? Do we need to disconnect the SDI before changing a dead BP-9 on the back of the camera even if the second BP-9 is still running the camera?

It seems to me this should only apply when connecting power to a monitor when that monitor is being powered by the camera or a battery connected to the camera. Otherwise I don't see how a circuit could be formed. But it would be nice to get some clarity from Red.

 

[Siddhu S.]

I think I and others are looking for a bit more clarity on this warning. Does it include dedicated monitor batteries, or just batteries that power the camera? Do we need to disconnect the SDI before changing a dead BP-9 on the back of the camera even if the second BP-9 is still running the camera?

It seems to me this should only apply when connecting power to a monitor when that monitor is being powered by the camera or a battery connected to the camera. Otherwise I don't see how a circuit could be formed. But it would be nice to get some clarity from Red.

Thank you for phrasing the questions on people’s minds so eloquently! I for one also want clarity on these issues as the instructions from the manual which I’m following, make it “cumbersome” to work on set as every time a battery needs to be changed (whether on the camera or monitor - I’m talking BP-955s and Sony for the SMallHD ), I turn off the camera and monitor, disconnect the SDI, swap batteries, re-attach the SDI, then reboot camera and monitor. All the while the talent and client are standing around waiting for this process to complete.

 

[Blair S. Paulsen]

Attaching any cable or battery with a voltage already present risks a spike at the moment of connection. Typically, this is dealt with by providing a safe, low resistance ground path (referred to as "earth" in the UK) so any spikes are harmlessly discharged. An SDI cable uses BNC connectors which are designed to completely isolate the signal on the center pin, with ground handled by the outer barrel. A shield/jacket running the length of the cable is intended to provide a near zero impedance route to ground. This has been working fine for decades.

What changed? Unless it's been way under the radar, DSMC2 bodies do not have this issue. The 12g version of SDI does handle a higher data rate than 1.5 or 3g, but the ground facility - on a properly made cable with full integrity - should be roughly the same.

Raw speculation alert: Does the larger body and heat sinks of the DSMC2 provide a better current dissipation capacity?

What strikes me as a potential "fix" would be to only use battery plates with built in, short run batteries in the plate itself. Any spikes created when swapping power could be absorbed by a correctly specced "back up" battery. We used to use the small RedVolts in the side handle for live swapping rear bricks, avoiding reboots. IIRC, PAG and IDX both offer V mount plates with internal gel cells capable of 2-5 minutes of run time.

I certainly don't claim to know exactly what's going on, or if my suggestion of a small battery in the mix would resolve it. That said, perhaps Ryan or some 3rd party could suss it out and, if practical, design a battery plate with a power interface able to, in the immortal words of Barney Fife "nip...it...in...the...bud".

Cheers - #19

 

[Robert Hofmeyr]

Attaching any cable or battery with a voltage already present risks a spike at the moment of connection.

Hi Blair. I think the ground loop is formed when powering the monitor and camera from the same source. If you power the Komodo from a v-lock, then plug in a monitor via d-tap or 2 pin, the +ve could connect first, resulting in the BNC cable briefly completing the circuit. It could be more complicated than this. See this video: https://www.youtube.com/watch?v=YFGgc8xUrvE. But I think separate power sources for monitor and camera will mitigate the problem (even if we don't disconnect the BNC when changing batteries). Would love confirmation on this though.

I think the reason for the increased number of issues is not the smaller body of the Komodo. It is more likely the fact that a larger number of Komodo owners are powering their monitors via d-tap or 2 pin cables, combined with some issues with the BNC connector on the camera itself where the metal petals get bent apart resulting in a poor connection.

 

[Blair S. Paulsen]

Two birds

Two birds

Gotcha Robert. Your notes might answer my question about "what changed" between DSMC2 and Komodo.

I still think there might be some interest in a power solution that included a short run battery that kept current flowing to camera and monitor while swapping bricks. Following a particular power up sequence once or twice a day is a manageable burden as long as there is no down time during shooting. Based on my experiences with using the RedVolts in the side handle as a reserve power source, it can be a real life saver when a brick goes down at the worst time.

Cheers - #19

 

[Michael R]

Our Komodo SDI failed on set today. The Komodo was powered via a Titon Micro on a Tilta Vlock plate and the SmallHD Focus Pro was powered by its own Sony LP. I have so far been unable to get the SDI output working again. Literally in the middle of a shoot. Unreal. Had to frame an interview on the postage stamp top screen. Hope it’s in focus.

Is it done for? No chance of recovery? Does this mean we have to ship this thing in and wait? We ordered in November and received at the end of March. We’ve used it on 4 sets and today it failed us after all those months of waiting.

The working theory that this can only happen if the monitor and camera are being powered from the same source is disproven by my experience today.

Pretty outraged by this if I’m being honest. Our main camera is a Weapon 8K and we’ve never had an issue in the 4 years of ownership. No weird battery and SDI dances have ever been performed.

What’s going on here?

 

[Siddhu S.]

Our Komodo SDI failed on set today. The Komodo was powered via a Titon Micro on a Tilta Vlock plate and the SmallHD Focus Pro was powered by its own Sony LP. I have so far been unable to get the SDI output working again. Literally in the middle of a shoot. Unreal. Had to frame an interview on the postage stamp top screen. Hope it’s in focus.

Is it done for? No chance of recovery? Does this mean we have to ship this thing in and wait? We ordered in November and received at the end of March. We’ve used it on 4 sets and today it failed us after all those months of waiting.

The working theory that this can only happen if the monitor and camera are being powered from the same source is disproven by my experience today.

Pretty outraged by this if I’m being honest. Our main camera is a Weapon 8K and we’ve never had an issue in the 4 years of ownership. No weird battery and SDI dances have ever been performed.

What’s going on here?

Out of curiosity, how did it happen?

 

[Mike P.]

Because DSMC2 only has SDI via a module, maybe it's being grounded/dissipated by the connection to the brain (making it less likely; the +ve needs to travel through two physical connections before the -ve hits)? Also DSMC2 is only 3G SDI, which might make just enough of a dissipation/desensitize difference to prevent the port from burning out.

Other than that, was it a shielded 12G SDI cable?