What the Raw/FX button does depends on a couple of settings.
First choose your base format by pressing the INFO button and on the bottom row/second from left of that screen is FILE FORMAT. choose your base preference here.
Next go to the MENU under BUTTON CUSTOMIZATION. In RAW/Fx BUTTON you can choose CANCEL AFTER 1 SHOT or not .
Next highlight the three format changes, one at a time by pressing the down arrow and then the right arrow on each. you can select the format to change to. for example the first "JPEG" you can select the change to JPEG, RAW, RAW+. use the up/down arrow keys, make your selection and press OK. then move on to the next.
I have mine set to change from RAW to JPEG and JPEG to RAW and RAW+ to RAW+ and CANCEL AFTER 1 SHOT UNchecked. I usually have my base format as RAW, so the first press of the RAW/FX changes it to JPEG. It stays like that till I press RAW/FX again or turn the camera off.
A little long winded but I hope it's clear.
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