The Blackmagicdesign (BMD) website has a number of different SDI converters in its range, which differ significantly in terms of their features and performance. Those who work with the ATEM Mini usually get along well with the basic version, the SDI MicroConverter series, as these formats cover up to 1080p60 (3G-SDI).
The very compact converters are available in both unidirectional and bidirectional versions.
In order to be able to reliably bridge longer distances in terms of signal technology, it is advisable to switch from HDMI to SDI-based transmission. With well-shielded cables, signals can be transmitted over distances of up to 80m and more. Two types of converters are required for cameras without an integrated SDI output. Once from HDMI to SDI and on the other side on the ATEM Mini, the reconversion from SDI to HDMI. If you own a BSS professional case with an SDI feature, the latter two converter types are already integrated in the case.
The SDI MicroConverters are small and compact and can be powered via the 5V voltage input via a USB connection. In our test with such a 5V-supplied pair of converters on the ATEM Mini, the following behavior was observed: Input 2 (only this one) had problems building up the image. This behavior was tested on two. ATEM Mini absolutely identical. Why exactly or only input 2 is affected by this behavior remains speculative. What is certain, however, is that inputs 2-4 are significantly less sensitive than the low-latency input 1 which should preferably be used for critical connections.
Better signal strength through MiniConverter series
If you change the converter on the camera side and use one from the MiniConverter series instead, it will deliver a signal to all inputs without any problems. These 12V powered modules appear to provide signal amplification in contrast to the smaller 5V versions. At least these do not have such a high signal loss and this has an extremely positive effect on signal stability.
Wherever possible, use converters from the Mini Converter series. In addition, the resolution and refresh rate can be set on most devices in this series.