topic Re: Is it harmful to continue using a lens with damaged IS? in EF & RF Lenses

Is it harmful to continue using an EF 70-300mm lens with damaged IS?

flamer800 — Tue, 04 Feb 2025 14:43:48 GMT

Hello, hope this is the right place to post.

I have a Canon 70-300mm f/4-5.6 IS USM (Mark I from 2005) and the IS seems to be malfunctioning when the lens is at 70mm. The image in the viewfinder will jump around and jitter, and the lens will also make loud noises. This problem disappears when the lens is zoomed in, or if the IS is turned off.

Video: https://youtu.be/XH9WljNelq8?feature=shared

I don’t mind that the lens cannot be used at 70mm anymore, but I am more worried that continued use will further damage the lens and make it unusable even when zoomed in.

Anyone have advice or solutions?

Thanks!

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 01:30:15 GMT

Are you sure the IS (Image Stabilization) is malfunctioning. What camera are you using this lens on. If adapted to the EOS R series are you using the Canon brand mount adapter. If so which model are you using. I noticed the exposure was changing a lot in the video. I can hear what sounds like the aperture motor which can be noisy in old lenses. Old lenses the aperture motor can be picked up by the camera's microphone when recording video.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 01:55:33 GMT

Hello, I thought it would be the IS since it seems to happen with movement and is not present as soon as stabilization is turned off.

The lens is being used on a EOS 6D, so no adapter.

Do you think the jumping around could be caused by something else?

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 02:04:29 GMT

I did not see it jump around in the video but I do hear the noise you’re describing. Are you recording video what is the aperture set to. Are you zooming in and out or is it at one focal length. That’s a variable aperture lens. The more you zoom in the smaller the aperture. A lot of old lenses have very noisy aperture motors. Which is fine for stills but video it’s not. Anytime the Image Stabilization is on its stabilizing. Even if you set the camera down in the table. Early EOS film bodies it was normal to see the image in the viewfinder to shake or jump. That’s why I asked what camera you’re using. That should NOT happen with an EOS Digital Camera.

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 02:15:06 GMT

Can you post another video with the IS turned off. I noticed that every time the lens made that sound. The exposure changed. Is this lens new to you or have you owned it for a while now. I’ll get my other colleague’s opinion on this. It’s too coincidental that every time the noise happens the exposure changes.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 02:25:11 GMT

Thanks,

The jumping I am referring to is the rapid shaking of the image. It is set to only one aperture and focal length, which is 70mm at f/4. If I zoom in even a tiny bit, the problem disappears, which I thought was strange.

Because of the shaking, it is difficult to take photos at 70mm

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 02:24:04 GMT

Thanks,

Here's the other video. IS is turned off, lens is at 70mm and f/4.

Second video: https://youtu.be/fjvv10HF6Qs

The problems don't seem to show up here. The lens is new to me, but I bought it used.

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 02:27:08 GMT

You do realize when you zoom in the lens changes the aperture to something smaller right. Just going from 70mm to 100mm makes the aperture smaller to F/4.5 the aperture doesn’t always stay at F/4 even if you set it to that. Try setting a small aperture such as F/11 and press the depth of preview button. If the lens continues to make that. Press the button multiple times and listen closely.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 02:39:11 GMT

Hello,

Yes, as I specified before, the problem is not tied to aperature, but to focal length. At 70mm, the problem persists at f/4, 8, 11 or whatever you set it to. The sound and image are also not abnormal when pressing the depth preview and panning the camera

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 02:39:39 GMT

This does appear to be an IS issue. The noise and the changes in exposure made me think the aperture motor in the lens. Are you actually pressing the depth of field preview in the test. Just setting the camera to a certain aperture doesn’t make it stop down.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 02:53:53 GMT

Yes, I am pressing the button, seeing it dim, and hearing the sounds it makes as I move. However, I think you were right that it is an aperture problem (that appears at 70mm exclusively for whatever reason.)

I can see in the viewfinder that during the tests, the aperture seems to be changing. The lighting still changes, and the aperture number in the viewfinder sometimes will rapidly flicker to a different number, even though it is on Manual mode and a set focal length. I think it goes to 5.6 whether or not I am above or below that value

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 02:57:43 GMT

BTW, my apologies if my responses are confusing or not helpful. The problem isn’t happening every time so it’s difficult to replicate and describe

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 03:06:13 GMT

Are you zooming in the lens during the test. That will make the aperture change. Zooming in from 70mm to 100mm will make the aperture change from F/4 to F/4.5 which is normal. But if you’re still at 70mm and the F/# changes from F/4 to F/5.6 without you changing it something is wrong with the lens. If the lens falsely reports the F/ number it throws off the exposure. It can also affect the lens’ IS too. That’s probably why the exposure was jumping around anytime I heard the sound. Can you show a recording of the viewfinder when the F/# rapidly flickers. Does it rapidly flicker on the rear and top LCD screens too. Or just the viewfinder only.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 03:35:50 GMT

I spent a while trying to capture the f number changing on camera, and was only able to get a shot of it happening from f/4 changing to f/5.6 with live preview. It also changes in the viewfinder, though. I'd post a video but I can't recreate it consistently.

It happens with most often with rapid movement. I think focusing and zooming out the lens out to 70mm might also cause it happen right after, although I couldn’t get it on video.

https://youtube.com/shorts/hQY-Vi5C6tU?feature=shared

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 03:41:51 GMT

I saw in the video it switched between F/4 and F/5.6 without intervention multiple times. Ie you zooming in or out or manually changing the F/ number. Focusing won’t change the selected aperture. Only zooming in will. Because it’s a variable aperture lens. The lens works differently than others. The way your lens is designed is that at 70mm it’s physically longer than it is at 300mm. Your lens is what’s called a reverse zoom lens. As you zoom in the lens physically gets shorter not longer like most lenses do. Most of the time when you zoom in with a lens it physically gets longer. Then when you zoom out it gets shorter. The flex cable in the lens is physically longer at 70mm than 300mm. That’s why the aperture works correctly at 300mm or any focal length longer than 70mm. The flex cable is shortest at 300mm. But at 70mm it’s changing by itself and the aperture motor gets very loud.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 03:58:33 GMT

Thanks for the explanation.

Im not entirely sure what you mean about a reverse zoom though?

The lens is longer when it is at 300mm than when it is at 70mm.

I suppose if it is a cable issue like you’ve said then the lens will be fine at longer focal lengths.

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 04:22:02 GMT

I know it’s hard to understand. When you zoom in and out. Externally what you see is the exact opposite what happens inside the lens. Hence why it’s called reverse zoom. So even though zoomed in at 300mm the lens looks bigger. Internally the lens is actually smaller and vice versa. If you’re within the return period I would return the lens as it is not functioning properly. If it can’t be returned I would contact Canon to see if they can repair it. Get a quote first BEFORE repairing it. Repairing it can easily exceed the value of it. If they can’t or it exceeds the value. Look into the Canon EF 70-300mm F/4-5.6 IS II Nano USM lens. This lens is a great improvement over your current lens. It also uses a much faster Nano USM AF motor. Compared to the slower cheaper Micro Motor USM which doesn’t support Manual Focus Override in AF mode. Like the new version II lens does. Or you can look at the EF 70-300mm F/4-5.6L IS USM model but it will be much more expensive than the version II model because it’s geared to toward pros. This variant of the lens uses the original fast Ring Type USM AF motor. Focus can be overridden in AF by turning the focus ring at any time.

Re: Is it harmful to continue using a lens with damaged IS?

flamer800 — Mon, 03 Feb 2025 04:41:16 GMT

Ty for the info and help. I’ll make do for now until I can get an upgrade

Re: Is it harmful to continue using a lens with damaged IS?

deebatman316 — Mon, 03 Feb 2025 04:47:49 GMT

I’ll caution you though if you go down the repair route. Canon usually stocks parts for 10 years after the product is discontinued. That lens was discontinued back in 2015 or 2016. It’s very likely that they may not have parts for it anymore. I’ve seen some discontinued lenses only have support for 3 years after discontinuation. Canon ran out of parts for that lens quickly because it was a popular lens among professionals.