Source: Olympus America Website
E-M1 mkII Version 1.0 updates to version 1.1
– Stability of RAW file information has been improved.
E-M1 mkII Version 1.1 updates to version 1.2
-Improved color reproduction of EVF.
-Corrected the issue of other brand flashes not flashing for High Res Shot, Focus Bracketing, and Focus Stacking.
-Corrected issue of Rec View screen not displaying in the rear monitor when using EVF to shoot photos.
-Corrected issue of home position of AF target not being retained when the power is turned off.
-Improved stability of the battery level indicator.
-Improved noise reduction of sequential shooting while the lens’s IS is on.
-Flash controllers manufactured by Profoto are supported.
E-M1 mkII Version 1.2 updates to version 1.3
-Corrected issue of AF Targeting Pad not functioning.
E-M1 mkII Version 1.3 updates to version 1.4
-Improved stability of operations when shooting while utilizing the EVF.
E-M1 mkII Version 1.4 updates to version 2.0
-New art filter [Bleach Bypass] has been added.
-Possible to use focus stacking photography with “M.ZUIKO DIGITAL ED 12-100mm F4.0 IS PRO”.
-Small targets have been added to AF target mode.
-Possible to set a maximum of 35 pre-shutter frames for Pro Capture shooting.
-Display has been improved to show that Pro Capture shooting is recording.
-“Flicker Scan” has been added so it is possible to reduce flickering by fine adjustment of shutter speed while looking at the live view when using electronic shutter.
-Fisheye compensation photography has been added for use of M.ZUIKO DIGITAL ED 8mm F1.8 Fisheye PRO. You can view the effects in live view while shooting images.
-Possible to set zoom ratio during playback. Also, added pixel equivalence display to zoom ratio.
-Pro Capture shooting is available for additional lenses.
-Display of remaining battery power has been improved.
-Response when assigning AF to AEL/AFL button has been improved.
-Stability of camera operation when using OLYMPUS Capture has been improved.
-Stability of image stabilizer operation when shooting video has been improved.
-Performance of C-AF when shooting still images has been improved.
-Color reproduction of photographed images has been improved.
-Stability of operation when shooting still images has been improved.
-Corrected issue of autofocus (AF) function not operating correctly when using the “LEICA DG ELMARIT 200mm F2.8 / POWER O.I.S. (H-ES200)” interchangeable lens produced by Panasonic.
E-M1 mkII Version 2.0 updates to version 2.1
-Corrected issue of C-AF not operating correctly when using the “LEICA DG ELMARIT 200mm F2.8 / POWER O.I.S. (H-ES200)” interchangeable lens produced by Panasonic.
E-M1 mkII Version 2.1 updates to version 2.2
-Stability of operation when shooting still images has been improved.
-Corrected issue of C-AF not operating correctly when using the “LEICA DG SUMMILUX 25mm / F1.4 ASPH.(H-X025)” interchangeable lens produced by Panasonic.
E-M1 mkII Version 2.2 updates to version 2.3
-Wireless radio commander FC-WR is now supported.
-Stability of operation when using SD card (UHS-II) has been improved.
E-M1 mkII Version 2.3 updates to version 3.0
-C-AF+MF to AF system
-5×5 to AF Target Mode
-C-AF Center Start mode and C-AF Center Priority mode
-Drive Priority and Detail Priority to Low ISO Processing when shooting still images
-L100 to ISO sensitivity setting
-“OM-Log400” to video picture mode
-Instant Film to Art Filter
-Frame Rate Priority to Live View Boost 2
-Now possible to select the number of shot between 3 and 15 when shooting with Focus Stacking.
-Enhanced performance of AF, High-precision focusing even when shooting dark scenes and low-contrast subject (with F/1.2 lenses).
-New AF algorithm from the OM-D E-M1X is included on the OM-D E-M1 Mark II
-Single AF (S-AF) enables accurate focusing on the subject even with mixed perspectives
-Improved quality of still images. (apparently 1/3 stop better ISO noise)
-Now possible to play back images and change settings while writing to a card.
-Added Selecting Multiple Pictures function.
-Anti-Flicker Shooting function
-Now possible to develop RAW data at high speeds in Olympus Workspace by using the camera’s image processing engine.
E-M1 mkII Version 3.0 updates to version 3.1
-Stability of operation when shooting still images has been improved.
-Stability of EVF operation when the camera is turned on has been improved.
(Crashing with C4K fixed as well as AF in video)
E-M1 mkII Version 3.1 updates to version 3.2
-Possible to use focus stacking photography with “M.ZUIKO DIGITAL ED 12-45mm F4.0 PRO”.
-When EVF Auto Switch is set, you can select how the viewfinder is displayed when the monitor is open.
E-M1 mkII Version 3.2 updates to version 3.3
-Possible to use in-camera focus stacking mode with “M.ZUIKO DIGITAL ED 100-400mm F5.0-6.3 IS”.
-Image stabilization performance when using “M.ZUIKO DIGITAL ED 100-400mm F5.0-6.3 IS” has been improved.
* Roll compensation is available with the image stabilization function of the body, along with the pitch and yaw image stabilization function of the lens.
* The “M.ZUIKO DIGITAL ED 100-400mm F5.0-6.3 IS” is not compatible with 5-axis Sync IS.
E-M1 mkII Version 3.3 updates to version 3.4
-Possible to use focus stacking photography with “M.ZUIKO DIGITAL ED 150-400mm F4.5 TC1.25x IS PRO”.
-Stability of image stabilizer operation when shooting video has been improved.
E-M1 mkII Version 3.4 updates to version 3.5
-Possible to use focus stacking photography with “M.ZUIKO DIGITAL ED 8-25mm F4.0 PRO”.
E-M1 mkII Version 3.5 updates to version 3.6
-Possible to use focus stacking photography with “M.ZUIKO DIGITAL ED 40-150mm F4.0 PRO”.
-Improved precision of focus when using single-focal-length lenses.