The camera obscura is a fun thing to play in – it is the tourist-site attraction with the dark room – in which you see a rather dim image of the outside scene projected upon the back wall from a tiny lens or tinier pinhole in the front wall. Sometimes there is a periscopic lens that projects a 360º image down onto a round table in the dark. You can see everything moving around you – but it is too dim to record it.
This novelty was the first stage of the science that eventually developed into your digital camera. Unlike your present equipment, it does not need batteries, and is unlikely to be replaced in two months…
The trick has been done in hotel rooms, aircraft hangers, and pup tents. Sometimes experimenters have contrived to use low-sensitivity photo paper to make a negative that records literally month of the scene outside -buildings sans people and skies sans clouds.
If you would like to so something of this with your modern equipment I suggest that you get a Lee Big Stopper filter and the associated holder system for the front of your DSLR or a pinhole lens cap and a sheet of dark filter material for your mirrorless camera. You can set the ISO at the very lowest for your equipment, bolt it to a tripod, and open the shutter for as long as the battery will last. Something will record and if it doesn’t end up being science at least it will be art.
The heading photo is taken with a pinhole on 4 x 5 film in bright sunlight. No lens, a minute of exposure. Pure gambling, I assure you.