Flexible priority (Fv) exposure mode, what it is, & how to use it

Flexible priority (Fv) mode features on the EOS R series of cameras. It’s a mode that suits many photographic situations, but is poorly understood by camera owners.

EOS R and EOS RP, both include flexible priority exposure mode. From recent workshops I’ve provided for EOS Training Academy it’s clear that many owners are not using Fv mode. It’s also clear that it’s a lack of understanding of what it does and how to use it.

Why would you use flexible priority (Fv) mode?

Imagine being able to take an initial quick automatic exposure photo. Then be able to take control of one of the key exposure controls, shutter speed or aperture for a second shot with more of your creative input. This is what flexible priority does really well.

Try leaving the camera in Fv mode, with the camera automatically setting shutter speed, aperture and ISO. Now you can take a photo quickly in almost any situation and have the camera determine the exposure. You will get a reasonable exposure of the subject.

Like many photographers you want to prioritise some aspect of the shot for your second frame. Flexible priority lets you choose any of the exposure settings to override, even all of them.

Let’s say you’re an inexperienced photographer, maybe just moving off auto mode, or using program mode much of the time. Sometimes you want to take more control of your photos, by determining the shutter speed or aperture, then flexible priority mode is for you.

What is flexible priority (Fv) mode?

Flexible priority mode is a mode like any other mode on the camera, you select it with the mode dial / mode button and then get to making photos.

Initially Fv mode is set to automatic settings for shutter speed, aperture, ISO and zero exposure compensation. Set like this, the camera is working as if it’s in program mode with auto ISO. Yet you can select any of these four parameters to override the camera determined values with your creative input.

Want to freeze the action? Then take control of the shutter speed, and let the camera control the aperture and ISO. It’s just like shutter priority mode with auto ISO.

Want to have more or less depth of field? Then take control of the aperture, and let the camera control the shutter speed and ISO. It’s just like aperture priority mode with auto ISO.

Want control of both shutter and aperture? Then set values for shutter speed and aperture, the camera will vary the ISO for a good exposure. It’s just like manual mode with auto ISO. And yes you can still use exposure compensation too.

Want complete control, shutter, aperture and ISO? Then set the values you want, the camera is working as if manual exposure was chosen. You are in charge of the exposure, but the meter will still give you a reference reading.

Want to quickly take a photo of a different subject in different light and need to reset all or some of the selected parameters to automatic? Flexible priority mode allows this with a range of buttons to reset single or all parameters to camera control.

How do you get the most from flexible priority (Fv) mode?

Take note of the orange cog icon

This orange “cog” is the icon Canon uses for the main control dial. The main dial is the wheel next to the shutter. The orange cog appears in front of the currently selected parameter, Av in the image above.

Change the selected parameter value by turning the main dial.

Change to another parameter by turning the quick control dial on the top of the camera with your thumb.

If you look at the EOS R top LCD panel, the currently selected selected variable has a frame around it. Aperture is selected in the photo above.

Look for underlined values

Any value that is shown with an underline, on the LCD or in the viewfinder is in auto and being determined by the camera. You’ll see the camera determined values when you half press the shutter, as above.

In the shot above, the aperture and ISO have been set to f/2.8 and ISO 1600, the camera can only vary the shutter speed to achieve the correct exposure.

Half-press the shutter before you change a value from auto

When the word AUTO is displayed and you turn the main dial, you start changing the selected setting from it’s minimum value. That’s 30 seconds for shutter speed, the widest open aperture, and your lowest available ISO.

When you half press the shutter the camera meters the scene and assigns it’s choice of values to the parameters. At this point when you move the main dial, the active parameter starts from the currently calculated value. This is vital for quick changes of shutter speed particularly.

Remember the order of parameters

The order of parameters is the same as in the viewfinder and on the bottom of the LCD, but different to the quick control screen if you use that. It goes: shutter speed > aperture > exposure compensation > ISO

Use the cross keys to reset single or all parameters to auto

By default the cross keys on the back of the camera are configured to reset parameters when using Fv mode.

Press the UP or LEFT cross keys to reset the currently selected parameter, and press the DOWN or RIGHT cross key to reset all parameters to automatic.

EOS R – M-Fn bar customisation for Fv mode

EOS R’s M-Fn bar can be customised to select specific parameters. For example if you want to use the left or right ends of the bar to select shutter speed or ISO with one touch you can. This provides a quick way to reset a specific exposure parameter.

I shoot in manual mode, is Fv for me?

In all reality flexible priority is probably not the best mode for you.

You’ll miss the ability to change shutter speed with one control, aperture with another and maybe ISO with another. I find it slower to have to use the different dials in Fv mode than in dedicated manual mode.

Flexible priority can do manual mode operation, but I don’t find it instinctive. I always need to look at what parameter is being changed before turning a dial. In this respect I personally find Fv mode frustrating to use as manual exposure mode.

Further reading

Canon USA’s guide to Flexible Priority mode written by Rudy Winston.