The Fujifilm X100F has two built-in shutters: electronic and mechanical. The electronic is a silent focal-plane shutter and has a maximum speed of 1/32,768. The mechanical is a nearly silent leaf shutter and has a maximum speed between 1/1000 and 1/4000, depending on the aperture. You can choose one or the other or have the camera automatically choose which it thinks is most appropriate for the situation.
When I purchased my X100F I didn’t think that the leaf shutter would be a big deal. I don’t do a whole lot of flash photography. I figured it would be a rarely used feature. Boy was I wrong!
A leaf shutter works more like an iris. There are blades, similar to aperture blades, inside the lens that open and close. It opens from the center outward. For this reason you can sync it to the flash at much higher shutter speeds. A traditional focal-plane shutter (which is found on most cameras) rolls across the frame, and doesn’t pair particularly well with flashes.

The Joy of Fishing – Huntsville, UT – Fujifilm X100F w/Flash
Leaf shutters are typically found on expensive medium-format gear. You rarely see them on other cameras. The exception is that Fujifilm has included leaf shutters on their X100 series, such as the X100F.
The Fujifilm X100F has a great built-in flash. There is a hotshoe should you want to add an external flash, but the fill-flash is more than adequate for most pictures. And Fujifilm has programmed the camera to perfectly balance the built-in flash with whatever lighting is available.
It’s truly amazing! The camera almost never gets it wrong. It just seems to know the perfect amount of light to add to the scene. The results are very natural looking. The pictures don’t scream that a flash was used.

Man In The Straw Hat – South Weber, UT – Fujifilm X100F w/Flash
I wasn’t much of a flash-photography guy, but now I am. I find myself frequently using the built-in flash on the X100F. The flash and the leaf shutter are key features of this camera!
It makes anything from family snapshots to portraits to back-lit scenes to dim-light situations a breeze to shoot. Any setting with unwanted shadows can be made better by using the flash built into the camera.
There are many things to love about the X100F. The retro look. The classic controls. The film simulations. The camera’s exceptional ability to balance fill-flash with the rest of the frame is perhaps the best part of it. And it is all made possible by the leaf shutter.

Let’s Roll The Moon Across The Sun – South Weber, UT – Fujifilm X100F w/Flash
but when i enter the mode Eletronic shutter ( ES) , the flash doesn’t function. Do you know why perhaps? thanks
You need to use the mechanical leaf shutter, not the electronic shutter.
Hi Ritchie
You have a very impressive blog! Thanks for all the info! Are you able to get speeds higher than 1/1000 on Aperture priority? On mine it stops at 1/1000. I saw that for earlier models this was a known thing but there’s nothing in the x100f manual about this limitation.
thanks a lot!