Unknown noise coming from lens while in video mode.
 

I tried doing a search and also skimming through the manual to see if they mention this noise I am hearing while in video mode but no luck. It only occurs when zooming in or out. The sound is very faint but enough for both me and the camera to pick it up. Just wondering if this is normal and if so, then what is causing it. I tried it with and without IS on, as well as autofocus on and off. Thanks!

here is a quick video. the noise is a lot more noticeable in the video.

weird. I just figured out that it doesn't happen when the lens is wide open, and every time it "clicks" the screen adjusts it's brightness. I am looking through the settings and I can't find what would cause this. Hope this is user error.

Ty,

I bet I know the problem, you have a variable aperture zoom lens. The lens says f4.5-5.6 or some other number range. This will cause your camera adjust the iris in your lens while zooming. This is probably the noise you are hearing and the sudden exposure shifts. Unlike a video camera these lenses do not seem to have smooth aperture transitions.

It is important that your lens is both constant aperture and parfocal if you are going to be zooming while shooting video. This is why I went for the Tamron 17-50 f2.8 lens over the kit 28-135 f3.5-5.6. Using the right zoom lens will allow you to zoom while shooting.

i thought this as well but I tried it on every aperture. So even when the aperture is not changing (f5.6-f22)the noise is still there.

Hmm, that's interesting I had an old 20-35mm f3.5-4.5 EF lens on my 7d for a short time and it exhibited the exact same noise and exposure issues when zooming. I'm stumped.

so you just tried this and yours is doing the same thing? If so, that makes me feel a little better, lol.

Try this
 

Maybe its your IS or you're on automatic mode.

Switch your camera to M. While zoomed out try turning your big dial right to change aperture. See if you get the same noise. My Canon 18-55 and Sigma 18-50 does the same thing. If your lens has an IS 'off' switch you should try that too.

Sorry, but there is nothing at all strange or unknown about this noise. It's normal for any EF still photo lens.

It's no secret that EF lenses make noise when they change aperture. You can't really hear it yourself when it happens, but the on-board mic in the camera is sensitive enough to pick it up and amplify it, making it very obvious upon playback, just like the noise made by Image Stabilization.

This audible noise is exactly the reason why the camera works the way it does in Auto mode when recording video: it will change ISO first, since it's a silent operation. If it runs out of ISO, then it will change shutter speed. It will only change aperture as a last resort due to the audible noise it creates, as you found out here. If you choose not to record video in Auto mode, then you need to be prepared to deal with this noise by avoiding changes in aperture while recording.

You have to keep in mind that this is a non-issue because these lenses are not designed for video. They're made for making still photographs. If you want to use an EF lens to record video without recording audio separately from the camera, then you'll have to work around this issue. The way to do that is to manually lock the exposure so that the aperture value does not change during the shot.

In this case, your particular lens makes noise during a zoom because it has a variable aperture which has different maximum values at each end of the zoom, for example f/3.5 at the wide end and f/5.6 at the telephoto end. As you pull the zoom, the aperture changes, making the clicks that you're hearing upon playback.

Avoid this noise by manually setting an aperture value equal to or smaller than the max. aperture value at the telephoto end., i.e., f/5.6 or smaller, so that there is no change in aperture as you pull the zoom. The other ways to avoid this are to switch to a constant aperture zoom lens (one that has the same max. ap. value at both ends of the focal length range), or switch to fixed-focal length prime lenses.

Frankly, zooms shouldn't be pulled during shots from these cameras anyway, but that's just my opinion on aesthetics.

Hope this helps,

sorry chris but locking the aperture so it does not change doesn't do anything as the noise is still there.

people on other forums were able to confirm this noise on theirs as well, so I am not worried. Also I will probably never shoot video with anything other than primes but the noise was annoying enough for me to want to know what it was.

thanks everyone.

Chris, I was on board with your description until I tested this out. I figured the same... that if you had your aperture set smaller than the max value the lens could do that the lens wouldn't adjust when zooming. However, my two zoom lenses I can stop them down (f10 for example) and when zooming in and out I still see jumps in brightness (along with the noise at the exact same time) at certain points of the zoom. It's as if it isn't truly setting it to manual. The camera is in the full manual setting during all this.

I had a similar issue with my 5dmk2 before i got my 7d. The 28-135/3.5-5.6 zoom would adjust while zooming even if it said the aperture was stopped down and constant. I actually found the effect was the least when wide open even though that was when the natural gradual lens exposure ramping was the greatest. I had to use it as is for a job i shot that had a bunch of snap zooms. it turned out pretty well since i was feeding sound from a boom operator and there was a lighting change during the zoom so the sound and light change were significantly lessened. I have not had this problem at all with my new 7d and my new sigma 24-70/2.8 at any aperture. This lens works great for me, it breathes less than any still photo zoom ive seen so far and works with my matte box (with a little work).

so this does not occur with yours, correct?