We just bought a bunch of D3500 cameras for a photography class. Since they have some video capabilities, and video is more my thing, I thought i’d give them a try. And, right off the bat, I’m stumped.
I set the camera to Manual mode, and turned on the liveview. Then I went back into the menu to disable the auto-ISO function. There’s also an option in the menu, under Movie Settings, to enable or disable Manual Movie Settings.
With Manual Movie Settings turned ON, the Command Dial changes the shutter speed as expected. Holding down the +/- button, the Command Dial does nothing. I expected it to adjust the iris. The camera behaves by claiming the iris is wide open, and there is no auto activity as I pan around in my office.
With Manual Movie Setting turned OFF, the Command Dial changes the shutter speed as expected. Holding down the +/- button, the Command Dial changes the f-stop number which appears on the camera’s back display, but does not actually change the exposure. Further, as I pan around my office, I can see the image brightening and darkening, indication of an auto at work. However, the displayed values for shutter speed, iris, and ISO are all unchanging.
Clearly, something is wonky here! With manual control enabled, I am unable to control the iris. With manual controls disabled, I can pretend to control the iris.
Thoughts on what’s amiss?
The difference between theory and reality is that, in theory, there is no difference between theory and reality.
I believe you have to turn off live view, then adjust the iris, and then go back into live view. I used to own a D5300 and shot in manual mode for video, and it was the same way. An online search should confirm this. It’s just how Nikon built these DSLR bodies.