If I ever find a good moving prop like a small fan, maybe I'll also re-shoot new previews to demonstrate how shutter speed affects moving objects.
Now, I'm just not sure how would one simulate a running fan with a picture. While for a static image you can have separated foreground and background and then apply effects for simulation (I know iPhone HEIC images have this property), for moving images you have to simulate the blur and the stillness, which is probably more difficult in terms of coding.
Also, there's around 4600 that are pure white, and something near that that are pure black, for the scene above (although more dynamic range would be very cool).
[1] 18000 * 0.5s shutter / 3600 = 2.5 hours for worst case shutter, /2 for average = 1.25 hours of exposure.
Sounds… reasonable I guess! I guess it can be simpler than I imagined. The owner of the site just needs a fan :-)
> Now, I'm just not sure how would one simulate a running fan with a picture.
I don't think it's necessary for this app. This is simulating what the camera sees, not what our eyes can see.