Fujifilm X-PRO2 & the Electronic Shutter

category: Cameras • 2 min read

All the Fujifilm X-cameras have both a mechanical shutter and an electronic shutter.

The mechanical shutter has a range from 15 minutes to 1/4000 or 1/8000 of a second depending on the camera model. Switching to the Electronic shutter the maximum shutter speed is 1/32000 of a second.

A Fuji 24 megapixel cameras has 4032 rows of 6032 pixels.

  • The mechanical shutter allows for the processor to read the 4032 rows of the CMOS sensor in one go.
  • For the electronic shutter, the processor reads the first row of 6032 pixels, then the next row, and the next row… until all the 4032 rows are read. It takes between 1/13th of a second to 1/25th of a second, depending on the camera model.
  • Once the global shutter is fully developed, the processor will do only 1 read to read all the rows in just one go, just like the mechanical sensor.

Benefits of the electronic shutter

  1. No wear and tear on the mechanical shutter.
  2. Much higher speed than a mechanical shutter.
  3. Much more consistent in term of speed. A mechanical shutter will have variations of as much as 5% from one shot to the next and the variation is bigger when doing burst than when doing single shot exposures.

Drawbacks of the electronic shutter

  1. The famous rolling shutter: A moving subject that is faster that the time it takes for the electronic shutter to read the full 4032 rows.
  2. Lower high ISO than a mechanical shutter. The limit is: ISO 12800.
  3. The electronic shutter is limited to 1 sec.
  4. The electronic shutter is terrible when taking photos under fluorescent lighting. Portions of the image may be exposed properly and portions of the same image be under-exposed… This is due to the timing of the electronic shutter and the timing of the fluorescent flickering. Fixed in the new firmware
  5. Flash doesn’t work because of the sync speed. If you are using a flash, the camera switches to the mechanical shutter.
  6. Rico Pfistinger claims that the mechanical shutter renders more dynamic range than the electronic shutter. I haven’t see that anywhere else.