You asked
Is the panasonic leica dg 10 25mm f 1 7 good in low light?
Here is what the site says about that.
From Panasonic Leica DG 10-25mm f/1.7: Panasonic Leica DG 10-25mm f/1.7: A zoom lens by Panasonic for Micro Four Thirds cameras, 10-25mm f/1.7. A zoom as bright as a prime, covering 20-50mm equivalent. Specs - Maker: Panasonic - Focal length: 10-25mm (zoom) - Maximum aperture: f/1.7 - Made for: Micro Four Thirds sensors - Mounts: Micro Four Thirds - Stabilised: no - Autofocus: yes What it frames like - On Micro Four Thirds (Micro Four Thirds): like 20-50mm on full frame; ...
From Sensor sizes: Is full frame worth it?: For low light, events, and portraits with very shallow depth of field, yes. For travel, street, wildlife on a budget, and most hobby photography, a good APS-C camera with good lenses is enough, and you'll carry it more. Lenses and light matter more than the last stop of sensor performance.
Quoted from this site's pages.