?

reflection in a bubble ?

Reflections of course, but not a bubble.

I have no clue.

Here's a tip. Something dark reflects the light =D

Biscuits in a shining cup, no pinhole!

No, not a pinhole, yet... Working on it. I already made the "frame/mount" with what to attach the printed slits on to camera. But then turned out the printer had ran out of ink =(

And what comes to guessing game, you are getting really close! The "food thing" you and Christine are trying to guess is not a food at all. But yes, a cup is involved. And what would be the round surface?

.... der Deckel von einem "Coffee to go" ?????

.... es ist mir auch völlig egal, WAS das hier wirklich ist ......

Sami, brauch` KAFFEE !!!!!!

Almost there.. Just forget the cover/lid and think more simple ;-)

Maybe a teaspoon?

Nope =P What is in the cup? ;-)

...water ?...

Not water, but guessing it is liquid is good enough. There's coffee in a large black cup. And you see the rim of the cup as the smaller "ring" also seen as a reflection. Then there's some reflections of a building seen as well.

Congratulations Erika! =)

Explanation image coming as soon as possible....

like the texture.........and colour tones...are those newton rings....

Thanks Graham.

By the way, the Newton rings is a total mystery to me. My only guess is, it's caused by sugar and "oil" in the coffee.

Congratulations Christine, for solving that "hot dog" is actually reflection of my fingers =D

Congratulations Erika, for solving the reflecting surface is a liquid. It is coffee in a large black cup more precisely =)

... eine leere Tasse ?
... kein Kaffee ?
... ich fass' es nicht .....

Oh there's plenty of coffee =) It is just a very large cup ;-)