Blackmagic Forum

Hi,

I recently bought a BMD studio camera 4K which has the built-in fibre optical connection (it hasn’t been delivered yet so not entirely sure what it looks like but the photo shows a standard SPF adaptor protruding from the optical port).

I’m assuming I’ll then purchase the BMD mini optical to SDI converter and a 6G SPF adaptor to slot into it.

I’m using this in combination with an ATEM Production Studio 4K 2 M/E, and a whole suite of other BMD devices and laptops, etc.

My questions:
- what type of fibre cable should I use? 30m / 50m length is all I need.
- what benefits are there to me using fibre rather than SDI (I’ve already got loads of 6G very high quality SDI)?
- will I be able to use the Talley lights directly from the ATEM mixer to the camera or do I need extra gadgets for that? Will that’s work over SDI or fibre?

Any thoughts most welcomely received!
Thanks
Tim

The camera doesn't come with an SFP so you will need to purchase one for the camera and the BMD mini optical to SDI converter + another SFP adaptor. The BMD SFP's are guaranteed to work but there are alternatives that others will probably share. I only use 1.5G so haven't has to purchase 6 or 12G modules.

Advantage over SDI is easier to run a dual core fiber rather than 2 DSI's.
ATEM Tally and Coms work over the fiber OK. You just set the camera ID in the camera to match the ATEM input used for the camera.

Cable like this works https://www.ebay.com/itm/Outdoor-50m-16 ... 2653716390

But you can get lots of other recomendations probably.

You don't need fiber if you are not going to run long lengths of cable.
2 SDI cables will do the same.

But if you need to span more length. Then Fiber is easier.
Just need 2 SFP's ( 1 for the camera and 1 for the converter) and a 12G mini converter to go from Fiber to SDI on the Atem side.

There is a lot of different fiber in the world. But for productions look at tacticle fiber. As normal LC fiber will break after a few times use or even the first time, depending on how carefull you are with the fiber.

Tacticle fiber is strong fiber were you can walk over.
And if you go fiber i would also advice cable with a sturdy lockable cable. Instead of just LC fibers coming out of the cable. As the weak point will then still be the end of the fiber cable.

For example look at Fieldcast A sturdy tacticle cable goes down from the fiber adapter. And the connector and cable wont break easily. We use Fieldcast fiber for 5 years now in rental. Have 1,5 kilometers of the stuff. And still going strong on the first reels i got.

Another plus point for fibre — if your work is on location in client premises — is that it’s immune from EM interference. Particularly induction (hearing aid) loops which typically run alongside the same wall you want to run a cable down!! VGA was the worst for it, SDI is better, but can still be disrupted by a nearby induction loop. The telltale sign is signal degregation when the audio gets louder.

One thing to explore is the price delta between 2 strand and let's say 12 strand.

We started buying 4 strand but over time moved exclusively to TAC-12. We invested in the termination tools and just starting buying rolls of the stuff (muuuuch cheaper). I prefer ST termination but the BMD have LC, I assume for space. ST feel more like SDI termination (and are more secure). When you get used to it, there's Fiber is almost limitless for transmission. Using different wavelengths, you can pack multiple cameras onto a single strand (we've done 4 on a strand but the theoretical limit is higher). You can also add IP, Audio, etc.

You do need to care for the cables a bit more. Keep the ends capped and have a cleaning and testing kit available. Kinks (under heavy gear or doors) can break up the signal. But in general, it's much better than copper. I use it for most runs over 30M.

a

Thanks for all the replies - very helpful.

So, using SDI connection from camera to ATEM I am still able to use talley lights, control camera colours, talkback (if I buy the BMD talkback unit) etc. The only reason to use fibre is for long cable lengths?

Thanks for the link to the armoured cable Ian, and the image of the fibre adaptor / Fieldcast info Daniel.

Cheers,
Tim

Tim you have a 2ME switcher. You dont need the Talkback converter if you are not going to use the fiber.

The 2me has a Talkback Input / Output. If you add a microphone amplifier and a Mic to the Talkback input. The signal is carried out by the SDI output to the camera. ( Also tally data, CCU control data )

Then hook up a powered speaker to the Talkback output and you hear the Cam operators from there.

Use a SDI Distibution amplifier to go to multiple cameras from 1 SDI output port.

Xtreemtec wrote:Tim you have a 2ME switcher. You dont need the Talkback converter if you are not going to use the fiber.

The 2me has a Talkback Input / Output. If you add a microphone amplifier and a Mic to the Talkback input. The signal is carried out by the SDI output to the camera. ( Also tally data, CCU control data )

Then hook up a powered speaker to the Talkback output and you hear the Cam operators from there.

Use a SDI Distibution amplifier to go to multiple cameras from 1 SDI output port.

Thanks Daniel - very helpful and I shall try this all out as soon as the camera arrives!

This forum has been invaluable. I hope at some point I’ll know enough to be able to help others, but there is so much to learn.

Thanks very much,
Tim

Xtreemtec wrote:You don't need fiber if you are not going to run long lengths of cable.
2 SDI cables will do the same.

But if you need to span more length. Then Fiber is easier.
Just need 2 SFP's ( 1 for the camera and 1 for the converter) and a 12G mini converter to go from Fiber to SDI on the Atem side.

There is a lot of different fiber in the world. But for productions look at tacticle fiber. As normal LC fiber will break after a few times use or even the first time, depending on how carefull you are with the fiber.

Tacticle fiber is strong fiber were you can walk over.
And if you go fiber i would also advice cable with a sturdy lockable cable. Instead of just LC fibers coming out of the cable. As the weak point will then still be the end of the fiber cable.

For example look at Fieldcast A sturdy tacticle cable goes down from the fiber adapter. And the connector and cable wont break easily. We use Fieldcast fiber for 5 years now in rental. Have 1,5 kilometers of the stuff. And still going strong on the first reels i got.

What a lovely piece of magic.

So would this work?
Buy two of those adapter beauties, put one on the camera just like the photo, and the other one, close to the Atem. And connect it with a mini converter Fiber to SDI to the Atem?
Would I still have tally,intercom,camera control from this fiber connection?

Thanks

Has anyone found that the 12G-SFP (ADPT-12GBI/OPT) have a minimum and maximum usable length? We put single-mode fiber in the facility because are patchbays would be about 230m from the far end panel. In theory, though, I could end up with two devices as little as 90m apart. In that instance, I'd hate for the SFP's to cook each other.

Thanks,
Steven

shoodtd wrote:Has anyone found that the 12G-SFP (ADPT-12GBI/OPT) have a minimum and maximum usable length? We put single-mode fiber in the facility because are patchbays would be about 230m from the far end panel. In theory, though, I could end up with two devices as little as 90m apart. In that instance, I'd hate for the SFP's to cook each other.

Thanks,
Steven

I live streamed two rowing regattas at Dorney Lake UK last weekend. We used 6 x Mini Converter Optical Fibre 12Gs to run three Ursa Broadcast G2 cameras along the 2km course. The cameras were at 2km, 1km and 30 metres from the vision mixer in the Finish tower. Worked perfectly all day for three days. Been using this combination on numerous events over the last two years. Never had a failure or line glitch.

We use both 12G Blackmagic and Fieldcast SFPs (and yes, you can mix them). The Fieldcasts are 2/3 the price of the Blackmagic version, with no difference in performance.

The fieldcast ones come even from the same Manufacturer BMD also buy they externally.

Anyway you will not COOK you SFP's. 10km SFP are perfectly capable of handling even 10m Fiber..

Not recommended.. But it wont kill it.

Thanks, y'all. I know there's a difference in these SFPs and the -ZR, -XR, -LR, and -SR versions that Cisco makes for their network switches. I just want to make sure I know which flavor I'm dealing with. There are SFP+ modules that specify putting an attenuator in place if the fiber length is lower than a certain percentage of the maximum transmit distance; these are mostly the modules designed for 40km and up, but they do point to IEEE 802.3ae (which I've not yet read) that specifies a minimum cabling distance of 2m, which is far less than I'm dealing with). I just wanted to make sure there isn't a minimum for these below which an attenuator might be called for.
Cheers,
Steven

shoodtd wrote:Thanks, y'all. I know there's a difference in these SFPs and the -ZR, -XR, -LR, and -SR versions that Cisco makes for their network switches.

And why your should NOT use Data SFP's >>>> viewtopic.php?f=4&t=49172&p=323070&hilit=pathelogical#p289398


Just spend the few dollars extra for proper video SFP's Because data SFP's will F you over sooner or later on a job!