topic Re: EF 70-200 L IS II USM Focus Falloff in EF & RF Lenses

EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Tue, 07 Oct 2025 01:34:08 GMT

Focus Trails off toward bottom

Hey all! This has been going on for a while but it seems to be getting worse. Is this something that can be adjusted or is it time for a new lens? Thanks!

Re: EF 70-200 L IS II USM Focus Falloff

jrhoffman75 — Tue, 07 Oct 2025 09:58:31 GMT

@rschleyer907 wrote:

Focus Trails off toward bottom

Hey all! This has been going on for a while but it seems to be getting worse. Is this something that can be adjusted or is it time for a new lens? Thanks!

Has the lens been dropped? If so, the lens elements could have been knocked out of alignment. You could contact canon support at 1-800-OK-CANON and see if they still service that lens.

Re: EF 70-200 L IS II USM Focus Falloff

shadowsports — Tue, 07 Oct 2025 12:30:02 GMT

Greetings ,

I still own this lens and unfortunately it went out of support 6/30/2025. It remains one of Canon's. best. Mine was retired when I upgraded to mirrorless.

You might be able to find repair locally if you search for camera repair and insert your ZIP code.

To be thorough we should probably ask the following:

Have you performed customary investigation/ troubleshooting? Are you shooting in RAW? What body are you shooting with? Do you have picture styles or in body corrections enabled? Have you used DPP to confirm your focus points? Is this the f4 or f2.8 variant? Assuming DSLR, have you made any changes in body to front or back focus?

Re: EF 70-200 L IS II USM Focus Falloff

ebiggs1 — Tue, 07 Oct 2025 14:39:10 GMT

A more simple question, are you shooting down at the subject? Its best to keep the lens perpendicular to your subject especially if you are using a large (low number) aperture. Perhaps you are shooting from the bleacher seats?

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Tue, 07 Oct 2025 16:16:11 GMT

It has been jostled but never dropped. Thanks for your input!

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Tue, 07 Oct 2025 16:21:06 GMT

Thank you for the thorough input! Sorry that I didn't include 2.8 in the description... Shooting in RAW with Mirrorless R6 and R6 MII. I will double check the other things before giving up completely. The test comparison I did was with two different bodies... R6 + RF 70-200 2.8 vs R6MII + EF 70-200 2.8. I will test the lens on all three of my bodies when I can.

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Tue, 07 Oct 2025 16:23:10 GMT

Good question! In this instance as in almost all of my other shoots, I was shooting from the player's box. I also shoot finish line photos for local runs which are at ground level so I don't feel that is a factor this time.

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Wed, 08 Oct 2025 02:15:41 GMT

I used the same body this time, one of my Canon R6s. Both photos were shot in RAW, taken at 1/200, f/2.8, ISO 400 at 70mm. I also took one photo with the EF lens on my R6 MII and had the same issue. I'm pretty sure it's the lens and not a camera setting. I found a local camera guy that is eager to take a look at it so we'll see how that goes! Thanks all for your help on this. If you have anything to add, please do!

Re: EF 70-200 L IS II USM Focus Falloff

ebiggs1 — Wed, 08 Oct 2025 16:34:37 GMT

Lens internals rotate. If it is a lens issue does it move when different FL are used? Does it change size when FL is increased or decreased?

Re: EF 70-200 L IS II USM Focus Falloff

shadowsports — Wed, 08 Oct 2025 17:07:40 GMT

Greetings,

Also of equal importance, are you using a Canon brand adapter with the adapted EF lens? Third-party adapters have not proven to be reliable.

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Thu, 09 Oct 2025 16:18:11 GMT

I rarely shoot at 70mm and that's what these two photos were taken at so my guess is that there's no change throughout the range of the lens, but I will double check that, thanks!

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Thu, 09 Oct 2025 16:19:01 GMT

I'm using a Canon adapter for the EF/RF conversion. Thanks!

Re: EF 70-200 L IS II USM Focus Falloff

rschleyer907 — Sat, 18 Oct 2025 16:30:34 GMT

I found a local camera repair expert that noticed the rigidity of the lens was a bit sloppy... (overall, minute but more than the lens should have), and he's taking a look at it. He said, "You've got some screws loose." and he'll have it back to me in under two weeks. I'll update once I've tested it. Thanks again for your input, all!