Blackmagic Forum

Hello all,

I'm getting in a tremendous pickle trying to make an informed choice of what spec of fibre to use for an SDI installation - any advice would be welcome here:

I need to permanently install/make use of existing installed fibre for some 12G-SDI runs. I'll be using the Blackmagic Mini Converter and associated 12G-SDI SFP Optical Module at each end of the runs, which will total about 50m.

I know that single-mode fibre seems to be typically specced for this - but it looks like this is suitable for much longer runs than 50m, so would be unnecessary for this case - so:

- Would multi-mode still work with these SFPs at this cable length?
- Is there a direct correlation between Gbps spec for fibre (100Gbps up to 100m for OM3) and the SDI data rate? i.e. OM3 up to 100m would support 12G-SDI.

Thanks for any insight here!

Devices that support fiber connection (network switches, SDI video, etc.) support different kinds of SFPs. If you already bought the SFP, then you will need to pick the matching cable. If the cable is already installed, then you need to pick the matching SFP.

Is it multi-mode (MMF) or single-mode (SMF)?

For MMF, OM3 and OM4 are the current standards. Typically, this is used for short-run 1Gb to 40Gb under 150 meters. OM3 supports 10Gb up to 100m. OM4 supports up to 150m. Shorter range for 40Gb data rate. 100Gb requires MPO style connection (multi-strand) or a higher OM rating.

For SMF, it's yellow. Though they are designed for long runs (up to 10km), it is very common in production environment sets to use SMF fiber even though the distance is less than 150 meters.

Hi,

Thanks for the response. The currently installed fibre is OM3 (multi-mode), which we are looking to supplement with additional runs.

Is it possible to use third-party networking SFPs which are OM3-compatible with the Blackmagic converters? I presume I'd need to find 40Gbps-capable SFPs, rather than using 10Gbps for 12G-SDI?

Thanks!

Moisie wrote:Hi,

Thanks for the response. The currently installed fibre is OM3 (multi-mode), which we are looking to supplement with additional runs.

Is it possible to use third-party networking SFPs which are OM3-compatible with the Blackmagic converters? I presume I'd need to find 40Gbps-capable SFPs, rather than using 10Gbps for 12G-SDI?

Thanks!

You can use third-party SFPs but they are not guaranteed to always play nice. Testing is needed.

Video SFP is different from network SFP. And the most common video SFPs are SMF base. You will need a 12G rated for your environment.