Why Does The Canon R5 Not Reading Aperture Value?
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Why Does The Canon R5 Not Reading Aperture Value?

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The Canon EOS R5 has an issue with the aperture value not changing or staying at 00 for some lenses. It does not show the change in aperture and how much the change is. 

This is a known issue among most users who pair it with a lens they already own and do not spend on a new lens that is 100% compatible with the body. 

In this article, I will be discussing Why does canon r5 not reading aperture value. 

What is Aperture? 

The aperture is the opening in the lens that allows light to move through the lens to the sensor or film. It is measured in f-stops. i.e. f/1.4, f/2.0, f/5.6 etc. It is the leaves in a lens that create the aperture hole.

The smaller the number the larger the opening in the lens and vice-versa. With the aperture amount, a photographer restricts the amount of light that passes through the lens.

Here is a demonstration of a lens diaphragm’s different aperture or aperture range.


(source: Stream it)

How does Aperture affect photography? 

It is one of the fundamentals of photography and without understanding how it affects photos one cannot take them how they desire.

Aperture controls two key elements.

  1. Depth of Field – Focus area of the image.
  2. Exposure – Brightness in the image.

Larger apertures take in more light so the depth of field is shallower. When the aperture is smaller there is less light recorded and the depth of field is narrower.

Here’s an image showcasing the different depths of fields due to aperture changes.


(source: gsmarena)

It also controls the brightness of an image or exposure in such a way.


(source: Photographylife)

Why does the Canon r5 not reading aperture value??

There are several key issues with the Canon EOS R5 that relate to aperture problems. Since the problem arises with this particular model of camera so often and not with every lens we can rule out the possibility of a single camera body being the only cause of failure.

An aperture of 00 means the camera is not able to control the lens properly or is not compatible enough to do so.

This can come from the dirt and rust deposited on the electrical contacts between a lens and camera or just that the lens is old enough that it needs or has manual aperture settings on the lens.

The camera body can be a point of failure if it fails to read the lens at all. The main reason for this issue may lie in the fact that it happens mostly with third-party non-canon lenses mounted with an adapter.

Aperture is a joint effort by the camera and the lens. If the result is the aperture value being 00 on every lens, then it is a problem with this particular camera body.

On DPreview users have mostly complained about the aperture amount being stuck, not that it doesn’t change at all. After setting it to a fixed aperture such as f/2.8 it gets stuck there until the lens is unmounted and mounted again. This issue happens with most sigma lenses when used with the Canon EOS R5.

There are other reported issues with the Canon R5 where the aperture cannot be changed beyond f/5.6 and f/11 despite the maximum aperture being f/2.8 and minimum f/22. This is because the aperture range is not set properly in the “Set aperture range” setting and is limited.


How do you fix the aperture on a Canon camera?

Ans: Choose manual exposure mode and then simply press and hold the Asterisk button and click the main dial along with it. This will fix the aperture on any Canon camera.

Why is my aperture locked on my Canon R5?

Ans: The aperture is locked because the multifunction lock mechanism on the R5 is turned on.

Should I shoot in aperture priority mode?

Ans: Not always. Aperture priority mode creates the best exposure, especially in low-light scenarios. It also has a faster shooting speed than manual mode.

What aperture is good for short depth of field?

Ans: Usually an aperture of 1.4 to 5.6 is the best for shallow depth of fields. The focus plane is between a few inches to a few feet.

How do you change the aperture on a Canon EOS R5?

Ans: By using the real mode dial or the control ring on the lens or adapter.

What aperture produces the sharpest image?

Ans: The sweet spot for the aperture that produces maximum sharpness is generally two or three stops from the lens’s widest aperture. An f/2.8 lens will have a sweet spot around f/5.6 or f/8.


If the aperture reading value is stuck at 00 then it is mostly because of dirt in the contacts and the camera not recognizing the lens properly. For a limited range, it is because the setting wasn’t tweaked to bring out the camera’s full potential.

Whether it is stuck or the reading is not shown, it mostly comes down to the compatibility of the camera and the lens.

I hope this article helps you out if you are facing the problem of Why does Canon R5 not read aperture value.

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