Eho mini box camera with color film

I tried using a 100 ASA color film with the Eho box camera. There is one shutter speed, around 1/50th sec I guess and bulb, plus two apertures f11 and f16. At the time of shooting i thought the speed was 1/30th but many poses came underexposed, so I think 1/50s is a proper estimate.

In bright sunlight with the f16 aperture

At night with the B setting, shutter stayed open around 15 seconds.

I got underexposed pictures just around sunset, when I thought that with 1/30 speed I would get a correct exposure.

and I got some light leaks - reflections from the shutter when I tried a contre jour picture

Eho mini box camera

This is a mini box camera made in Germany in the 30s.
It has a Duplar f11 lens, with two apertures f11 and f16, one shutter speed (1/30s ?) plus Bulb.
There are two tiny viewfinders for waist level shooting plus a wired frame for aiming on eye level.
Takes 120 film and makes 16 exposures 4.5x6cm.
I have put a Fuji Reala 100 ASA film in it.