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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

The SDI issues


Once again we get these non-answers to the actual questions and problems raised by people. In this video, they only show one kind of procedure in ideal situations.

Here's a list of potential situations in the real world:

- Power shutdown due to low battery (what then? Can't turn it on since battery has low voltage, but the battery still has power in it so what is the procedure?) This kind of thing happens all the time on set, camera is running, people are discussing a scene, camera turns off.
- Using V-lock batteries to power the monitor and camera at the same time?
- Hot swapping batteries on the camera?
- Using isolators or finding out which cables are approved (even shielded cables come in bad quality so shielded is not a guaranteed success)
- Monitor fails/shuts off for some reason?
- Cable wear and tear due to constant connecting and disconnecting and how that can cause problems when they fail.

The complexity of this topic needs a deep dive. We need to know solutions for ALL SITUATIONS that include problems like premature shutdowns on set, because they always happen, there's no way around it and it's necessary to have this deep dive in order to be able to put the responsibility on people renting the camera and not be forced to pay for stupid people renting gear and not properly using it. If information is available with solutions to common problems, it can be avoided. We need to have a list of approved cables, or preferably, cables in the Red store that's approved and tested by Red. We need to know if isolators are effective. We need to know how to proceed according to the listed situations above.

It's an insult to our intellect to make this kind of response to a problem that is essentially affecting a lot of people including those who actually follow these procedures and had problems anyway. We asked for a deep dive, for transperancy and we got a video using the Red support whitepaper as a script.
 
Is there any difference between the following products?

Allen Avionics : HD-VIT-75 : https://www.allenavionics.com/product-details/hd-vit-75
LEN : L4KGI 01 : http://www.len.co.uk/products-catalogue/products/4k12g-sdi-video-galvanic-isolator-barrel-style/

If the LEN description states : "Full DC galvanic isolation between equipment, both signal and ground path"
Does this mean it will prevent the RED SDI port being fried?

AJ

Robert Hofmeyr said:
I also assumed this, but then I saw that you can get 12G galvanic isolators: http://len.co.uk/products-catalogue/products/4k12g-sdi-video-galvanic-isolator-barrel-style/
Click to expand...
 
Antony Newman said:
Is there any difference between the following products?

Allen Avionics : HD-VIT-75 : https://www.allenavionics.com/product-details/hd-vit-75
LEN : L4KGI 01 : http://www.len.co.uk/products-catalogue/products/4k12g-sdi-video-galvanic-isolator-barrel-style/

If the LEN description states : "Full DC galvanic isolation between equipment, both signal and ground path"
Does this mean it will prevent the RED SDI port being fried?

AJ
Click to expand...

I think the main difference is that the Len version is 12G so it can pass a 4K signal. It is also more expensive. Red has not commented on the use of isolators, but as I understand it, they should protect the SDI very well. They are quite bulky, and a bit tricky to mount neatly. Someone on FB said Len was working on a dual output version of their 12G isolator. That might be quite useful.
 
Thankyou for the info Robert.


With my rather limited understanding of SDI - I have created a connection diagram below to get your feedback:

Q1) If a Single V-Mount is the source of power - would it still be necessary to disconnected the SDI cable from the EVF before replacing the battery?

Q2) For people intending to use the Kameleon with the Komodo - do they have a different SDI configuration - or will they be adopting the SDI plugging protocol?

Q3) The Kameleon has a 4 pin Lemo for power. I am uncertain of why it uses a 4 pin lemo rather than a just 2 pin lemo? (I want to replace the zakuto cable with a D-TAP with a 'safe' (shielded) 2-pin Lemo)

51368408675_9f5e95ce63_c.jpg


AJ
 
Antony Newman said:
Thankyou for the info Robert.


With my rather limited understanding of SDI - I have created a connection diagram below to get your feedback:

Q1) If a Single V-Mount is the source of power - would it still be necessary to disconnected the SDI cable from the EVF before replacing the battery?

Q2) For people intending to use the Kameleon with the Komodo - do they have a different SDI configuration - or will they be adopting the SDI plugging protocol?

Q3) The Kameleon has a 4 pin Lemo for power. I am uncertain of why it uses a 4 pin lemo rather than a just 2 pin lemo? (I want to replace the zakuto cable with a D-TAP with a 'safe' (shielded) 2-pin Lemo)

51368408675_9f5e95ce63_c.jpg


AJ
Click to expand...

Hi Antony. I'm afraid I'm not enough of an expert and I am somewhat confused myself. The Arri paper and article both talk about the SDI issue being a ground loop - which would require a single battery connected to the camera and then momentarily connecting the SDI accessory to the positive pole of that same battery before it is grounded. The SDI cable then briefly becomes the return path for the accessory's power. This is a real risk if you are using D-tap to power your Zacuto, but should not occur if you make sure you never plug or unplug the D-tap while a battery is connected and the SDI is connected. Replacing the D-tap with a lemo is probably a good idea.

Red's latest video does inform us quite clearly that "12G SDI kicks ass" but does not go into much depth regarding the cause of the issue. In the video they are using a monitor powered by a second battery - so a ground loop cannot be formed. What then causes a current large enough to blow the SDI is beyond my limited electronic knowledge. I understand that the grounds of the two different batteries could be at different voltages, and that this would then equalise through the SDI, but if the accessory and camera do not have chassis grounds (or these grounds are not connected) then this would happen anyhow when the SDI cable was connected after the battery was connected.

I believe the Freakshow splitter in your diagram is not an isolator. I think it has a fuse that will blow if a current runs through the cable, but I would not rely on a fuse if something as small the potential difference between the ground of the camera battery and the ground of the accessory battery can blow it.

I see you also have an isolator. I believe this will protect the SDI from any surges that may happen. As I understand it the isolator does not allow any current to get past, so it provides excellent protection for the SDI port. As mentioned above, I did see someone on FB say that Len is going to release a 12G-SDI isolator and splitter combo. If you get that it will simplify your rig a bit as it could replace both the isolator and the freakshow.

I'm sorry I could not be of more help. If someone understands this better than me, and can provide an explanation, I'd much appreciate it.
 
Last edited:
Christoffer Glans said:
- Using V-lock batteries to power the monitor and camera at the same time?
Click to expand...

I’m doing that every time I use my Komodo and my Small HD monitor. The screen is powered through the P-Tap of the SWX V-Mount adapter.
I turn on the screen then boot the camera, shutdown the camera then the screen, cable is connected at all time.
Now watching the latest Red video, I’m more than confused… Should I remove the cable before switching on and off?
Honestly I don’t get it.
 
vincent kardasik said:
I’m doing that every time I use my Komodo and my Small HD monitor. The screen is powered through the P-Tap of the SWX V-Mount adapter.
I turn on the screen then boot the camera, shutdown the camera then the screen, cable is connected at all time.
Now watching the latest Red video, I’m more than confused… Should I remove the cable before switching on and off?
Honestly I don’t get it.
Click to expand...

The SDI cable protocol applies mostly to connecting and disconnecting the battery/batteries. As long as you haven't removed or reinstalled any batteries, I think you're good to go with your procedure.
 
Robert Hofmeyr said:
Hi Antony. I'm afraid I'm not enough of an expert and I am somewhat confused myself. The Arri paper and article both talk about the SDI issue being a ground loop - which would require a single battery connected to the camera and then momentarily connecting the SDI accessory to the positive pole of that same battery before it is grounded. The SDI cable then briefly becomes the return path for the accessory's power. This is a real risk if you are using D-tap to power your Zacuto, but should not occur if you make sure you never plug or unplug the D-tap while a battery is connected and the SDI is connected. Replacing the D-tap with a lemo is probably a good idea.

Red's latest video does inform us quite clearly that "12G SDI kicks ass" but does not go into much depth regarding the cause of the issue. In the video they are using a monitor powered by a second battery - so a ground loop cannot be formed. What then causes a current large enough to blow the SDI is beyond my limited electronic knowledge. I understand that the grounds of the two different batteries could be at different voltages, and that this would then equalise through the SDI, but if the accessory and camera do not have chassis grounds (or these grounds are not connected) then this would happen anyhow when the SDI cable was connected after the battery was connected.

I believe the Freakshow splitter in your diagram is not an isolator. I think it has a fuse that will blow if a current runs through the cable, but I would not rely on a fuse if something as small the potential difference between the ground of the camera battery and the ground of the accessory battery can blow it.

I see you also have an isolator. I believe this will protect the SDI from any surges that may happen. As I understand it the isolator does not allow any current to get past, so it provides excellent protection for the SDI port. As mentioned above, I did see someone on FB say that Len is going to release a 12G-SDI isolator and splitter combo. If you get that it will simplify your rig a bit as it could replace both the isolator and the freakshow.

I'm sorry I could not be of more help. If someone understands this better than me, and can provide an explanation, I'd much appreciate it.
Click to expand...

A word about your "schematic". Since I have a Zacuto Kameleon, I needed one of those 2-pin to 4-pin Lemo cables. Zacuto has used a non standard pin wiring on their 4 pin lemo. ALL the commercially available 2-pin to 4-pin lemos are not wired correctly, so take great care. I had to order a custom cable from Alvin's that was wired to the Zacuto spec.
 
Great, now I'm hesitant to even use the SDI....good thing the app kicks so much ass I guess.

Question though....
Has anyone identified a common monitor/piece of gear that is killing these things?...zacuto EVF, Ninja v, Small HD, Blackmagic switcher etc? Or is it just all over the board?
 
Brian Roberts said:
Great, now I'm hesitant to even use the SDI....good thing the app kicks so much ass I guess.

Question though....
Has anyone identified a common monitor/piece of gear that is killing these things?...zacuto EVF, Ninja v, Small HD, Blackmagic switcher etc? Or is it just all over the board?
Click to expand...

My buddy is running a smallHD Focus Pro and hasn’t blown anything up, yet, and they’ve had it since late ‘20 or early ‘21. He runs it with its own battery. When I’ve shot with it, I’ve run it with a power tap cable coming off the CoreSWX batt plate to save weight and to only have to worry about one battery.
 
Bill Ravens said:
The SDI cable protocol applies mostly to connecting and disconnecting the battery/batteries. As long as you haven't removed or reinstalled any batteries, I think you're good to go with your procedure.
Click to expand...

Thanks for your reply Bill
 
Lentequip Releases Safetap Revision 4 to help with the SDI Driver Issue

Lentequip Releases Safetap Revision 4 to help with the SDI Driver Issue

Lentequip is releasing the redesigned SafeTap connector, revision 4. With this new release, we’ve implemented the output switching of the positive polarity power line. (Previously we were switching the negative polarity line due to component restraints). RED has recently tested the new revision 4 connector and indicated that it takes steps in the right direction in regards to the SDI Chip Driver damage issue which many of you know about on many cameras, at least as it relates to the potential damage coming from a PTap type connector. Essentially, when you connect a Safetap rev 4 to your P/DTap socket, you will ALWAYS make the ground connection first and foremost. Only once all the conditions are safe, the connector will then proceed to power up the connected accessory. All the previous SafeTap features remain in place. If you wish to learn more, feel free to contact us.
 
Was on a production with 2x komodos, one of which was my own, the other from a rental company. Had both komodos sdi output sent directly to vaxis 1000ft tx units, but my unit couldn't provide a signal. Its sdi out works on monitors (blackmagic video assist 12g and smallhd 702oled) but for some reason it wouldnt work on either of the vaxis transmitters. Has anyone else experienced this?
 
Ashley Tan said:
Was on a production with 2x komodos, one of which was my own, the other from a rental company. Had both komodos sdi output sent directly to vaxis 1000ft tx units, but my unit couldn't provide a signal. Its sdi out works on monitors (blackmagic video assist 12g and smallhd 702oled) but for some reason it wouldnt work on either of the vaxis transmitters. Has anyone else experienced this?
Click to expand...

Moat likely your SDI was not set to HD resolution.
 
Ashley Tan said:
Was on a production with 2x komodos, one of which was my own, the other from a rental company. Had both komodos sdi output sent directly to vaxis 1000ft tx units, but my unit couldn't provide a signal. Its sdi out works on monitors (blackmagic video assist 12g and smallhd 702oled) but for some reason it wouldnt work on either of the vaxis transmitters. Has anyone else experienced this?
Click to expand...

Bob Gundu said:
Moat likely your SDI was not set to HD resolution.
Click to expand...

Also…. Did you try swapping SDI cables? The Komodo seems to be really finicky about the cables it likes. The first time I shot on my friends, I used one of my “regular” thin cables(3G?) that I use with my F55 and Focus OLED. No issues. But after that, for some reason it wouldn’t work with it anymore and it only likes the (most inflexible, unwieldy, thick) 12G SDI cable that they bought for it after that, despite only spitting out HD.
 
Robert Hofmeyr said:
Brendan McCafferty on the Red Komodo Users FB group (from a couple months ago): "Currently all 3 of my ST Komodos are in for repair which is remarkable as we follow their procedures to a T. It seems that Red must address this with a recall / replacement board as this seems to be an egregious design flaw."

If it is possible for a guy who knows and follows the procedure to blow all 3 of his cameras SDI boards, then this is not to be taken lightly.
Click to expand...


Do you know how much RED charging for SDI repair?
 
Hi Everyone . Really concerned about that SDI port issue . Has i understand there is now very simple protocol to follow but very time consuming for real world film set .

My question is .
Would it be possible that IN camera '' RED KOMODO '' It self . To add a feature that will Cut power off or simpely disable the SDI port IN CAMERA . with a menue feature in a Update ?
Which will allow hot swap and keeping the sdi connected in any situations.

In my opinion its not possible but would make so much sens.

What do youguys think about it ?
 
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