Cactus gave a
live presentation about the RQ250 at CP+ 2018.
The presentation runs for ~25min but progresses rather slowly as it is held in English and Japanese (interleaved translation). It starts at the 3min 56sec mark and the RQ250 can be first seen live in 3D at 6min 22sec. It makes a very compact impression indeed!
Here's my summary of the additional details that were conveyed during the presentation:
The 250 Ws correspond to the power of ~3.5 x GN60 speedlights.
The RQ250 will have a full power recycle time of ~2s.
They designed their TubeOne flash tube so that it fills light modifiers as evenly as possible.
Here's a screenshot from the presentation that shows the difference between the illumination achieved by a bare bulb (left) vs a standard speedlight (right):
The difference is, as expected, significant and results in the bare-bulb flash creating a much bigger, and hence softer, light source.
The reflector was also designed to provide as even as possible light output. That's excellent news, AFAIC, because such a high quality light source will be far more useful in practice than a device with a Fresnel lens that has been optimised to produce a hot spot in the middle in order to manufacture a high GN number for marketing purposes.
Due to the fan-cooling, the tube will manage 50 consecutive full power shots without overheating.
The reflector part screws on. I think I would have preferred a click on approach, but perhaps it wouldn't have been secure enough, as one can attach accessories to the reflector. Colour gels, a honeycomb grid, and a snoot will be able to attach magnetically. So at least accessory changes will be very quick.
I was excited to hear that a swivel with an integrated umbrella holder will be included and that they are apparently trying to make the swivel double as a grip for hand-holding.
Both modelling light (demonstrated during the presentation at 18min 35sec) and AF-assist are realised through four LEDs.
The back-LCD is a 1.7" OLED display.
There is an optical slave and and a 3.5mm sync jack.
Firmware updates will be possible via a micro-SD card slot.
No information was provided on flash durations, colour stability, and pricing.
Overall, the RQ250 looks extremely promising to me!