Sony Alpha α290 does NOT have any video capabilities.
Video data
Tested by myself.This camera is not capable of working with video. It is probably just a photo camera.
Camera data
Lens mount: Sony A.
Crop factor: 1.5 in respect to a 35mm film. More crop factor means the sensor is smaller.
Other cameras
This camera uses the Sony A mount to attach lenses to it, and there are a lot of cameras using the same lens mount.
Search cameras with the Sony A mount.
What is clean HDMI
Clean HDMI output means that a camera is able to output a live video signal through HDMI without any graphics, marks, data, autofocus regions or any other thing that usually shows on the camera display.
The clean HDMI output only includes just the video, nothing more, so it can then be sent without any visual distractions to any other live video equipment (HDMI capture card, professional video switcher) for live video streaming or broadcasting.