Dual exposure
Back in the days of film, dual exposure was when you shot two images but without advancing the film between the two shots. The film would then be exposed two times and the resulting image was a combination of the two exposures.
These days most digital cameras offers dual (or several) exposures as an option available via the menu system in the camera. My Nikon Z50 for example has “multiple exposure” as an option in the photo shooting menu, just to give an example. In the image below I have shot the little toy cow two times moving the camera a bit downwards between the two shots. Not exactly a price winning image, but I think it works to illustrate how double exposure works:
With advanced post processing software like Photoshop, it is possible to combine the images long after they are shot, and this gives even more options for creative use of combining two or several images into one.
Only your creativity sets a limit for what you can use dual exposure for. It often creates images that clearly depicts a scene or a subject that you would not find in the real world. So the result can be e.g. dreamlike, surreal or just strange. In the example below I have put the cow from above into a glass bottle by shooting the cow first and the bottle afterwards.
I hope this gave you an appetite for trying out double exposure yourself. Only your imagination and creativity is the limit! Best of luck!
Related reading
What is exposure compensation?
What is the exposure triangle?
