topic Re: RF 15-35mm F2.8L IS USM Distortion Issue in EF & RF Lenses

RF 15-35mm F2.8L IS USM Distortion Issue

kghaviland — Sun, 14 Aug 2022 22:44:39 GMT

I've been shooting with an R5 and a number of different RF lenses with no issues. Everything is great. I recently purchased the RF 15-35mm F2.8 IS USM for landscape shots. The pictures all show distortion where for example trees on the left are slanting to the left and trees on the right are slanting to the right. This is after lens correction in Lightroom. Is this normal for this lens? Seems very odd for a lens made for landscape photography. I'm thinking there might be an issue with this particular lens. Any thoughts? Thanks!

Examples... note that I manually corrected (in addition to applying the lens profile correction) the last image to straighten up the trees but was unable to do it and have it look decent in the other pictures

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Tronhard — Mon, 15 Aug 2022 01:01:35 GMT

Hi and welcome to the forum:

Can you advise if the camera was actually horizontal, looking towards the horizon, rather than side to side?
Are the images from RAW or JPG files?
Can you look at the originals and see what the distortion looks like without correction please and maybe post an image of that.

To be honest, my first reaction is that Lightroom has applied the wrong kind of lens correction to the images or at least massively overcorrected.

A couple of things I would check:
Lightroom is using the correct lens for its correction algorithm.
Also, if you have Canon's Digital Photo Professional, try uploading your images to that and see what they look like there.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Waddizzle — Mon, 15 Aug 2022 00:59:45 GMT

I agree with Trevor. You might have an issue with LR. If you have DPP installed, I recommend looking at the images using DPP. Also, do the images look distorted when you play them back in the camera?

Re: RF 15-35mm F2.8L IS USM Distortion Issue

kghaviland — Mon, 15 Aug 2022 01:00:57 GMT

Thanks for the response. To answer your questions ... Yes, the camera was horizontal towards the horizon. These were from RAW files (Canon CR3). The slanted trees on both sides of the image are even worse in the original RAW files. The lens correction helped a tiny amount. The lens correction profile in Lightroom is using the correct lens profile at least it lists it correctly.

Kelly

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Tronhard — Mon, 15 Aug 2022 01:04:43 GMT

Bill: Can you focus on this issue while I help a young person with her choice of camera for school please?

Re: RF 15-35mm F2.8L IS USM Distortion Issue

kghaviland — Mon, 15 Aug 2022 01:05:04 GMT

By the way, I had the camera setup to capture both RAW and JPG files and the JPG files also exhibit the same massive distortion problem so I don't think it is an issue with Lightroom.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

kghaviland — Mon, 15 Aug 2022 01:38:28 GMT

Thanks for the response. The images are distorted in the camera preview as well. As are both the RAW and JPG files prior to any Lightroom engagement.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Tronhard — Mon, 15 Aug 2022 01:41:08 GMT

Good to know. I find it odd that the distortion is as shown in the original and in the form. Do you have access to another similar lens to see if that too gives the same result? Maybe go to a camera store and try some sample shots with one of theirs. I don't have that lens, so I can't provide any myself.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Waddizzle — Mon, 15 Aug 2022 02:43:02 GMT

I assume that these images were captured using a tripod that was level to the horizon. If you are shooting from a tripod, then Image Stabilization would need to be disabled on the lens and/or in the camera.

I believe the lens [AF : MF] switch overrides any setting in the camera. But, check the settings in the camera, anyway. I would expect the IS menu settings to be either greyed out, or simply removed from the menus.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

amfoto1 — Mon, 15 Aug 2022 03:48:54 GMT

This appears to be normal "perspective distortion" as occurs when you tilt the camera upward while using an ultrawide lens. Looking at your examples, the first few are the worst.... especially the 2nd image. I bet you were shooting down low to include the foreground log and had tilted the camera quite a bit for that one.

Your last two examples show very little or no distortion, so the camera was probably kept pretty level.

Perspective distortion can be corrected to some extent in post-processing. But it always involves quite a bit of cropping so you need to plan for that when taking the shot.

There are also lenses created specifically to help with this type of situation, Canon's TS-E or "Tilt Shift". These have movements that reduce the distortion. Canon makes five such lenses right now, ranging from 17mm to 135mm. The shorter focal lengths... 17mm, 24mm and 50mm... would likely be the most useful for landscape photography. None are currently made in the new RF mount, so it would be necessary to adapt EF mount lenses.

The TS-E lenses help, but there is a limit to how much distortion can be corrected with them. Often it's necessary to do some of the correction with the lens and a bit more of it in post-processing. The TS-E lenses are all manual focus only.

Without those lenses to work with, watch for this distortion occurring when you're taking the image. You should be able to see it in the viewfinder or on the rear LCD. It may help to put a grid on the screen (enable it in the menu). You may need to back up a bit and level the camera more carefully, to minimize the distortion.

I hope you don't mind, I experimented with your first two images and perspective correction in Photoshop. The first image cleaned up reasonably well and only needed a little crop. The 2nd image required a whole lot more correction, after which a heavy crop was necessary. Below are your examples, after this correction and crop...

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2) some other cameras, various lenses & accessories
FLICKR & ZENFOLIO
.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Tronhard — Mon, 15 Aug 2022 08:55:52 GMT

I agree with you. That is why is specifically asked if the camera was level in one of my first posts, and the OP seemed to suggest it was. but certainly any tilt from horizontal will result in a dramatic degree of distortions.

In the example image below the shots were taken absolutely horizontal in all axes with a 10mm lens (on an aps-c body equivalent to 16mm) their is no distortion of verticals

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Waddizzle — Mon, 15 Aug 2022 09:49:59 GMT

We cannot stress enough the importance of leveling the camera to the horizon when using wide angle lenses. The camera must not only be leveled side to side, but also front to back. You do not want the camera pointing upward or downward.

This effect is especially noticeable when photographing tall buildings. If the camera is angled upward, then the vertical lines of the building will tend to narrow the higher up the building you look. The narrowing effect is above the horizon because the camera is pointed above the horizon.

The opposite happens when your camera is angled downward. The narrowing effect is now below horizon, which is the shooting scenario that you seem to be experiencing. Your horizon is above the center of the image, which tells me the camera was tilted slightly downward.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

ebiggs1 — Mon, 15 Aug 2022 15:37:43 GMT

At this point I agree. You are not holding your camera/lens square to the world. As FL becomes less, meaning wider, the very more important it is you make sure there is no tilt in any direction. Not up nor down or sideways tilt. If you are pointed down just a bit perhaps not even enough to notice when looking at the scene, you will get distortion like you describe. It is just the nature of a WA lens.

It is possible to add enough off axis distortion that LR or DPP4 can't correct it automatically.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

AtticusLake — Mon, 15 Aug 2022 15:55:00 GMT

Since I have the exact same camera and lens -- R5 and 15-35 f/2.8 -- I thought I'd give this a try. Results attached. These were shot with the lens at 15mm, in RAW, then scaled down and converted to JPEG for posting here; but no distortion correction has been applied, either in camera or in post. No Lightroom was used (I don't even have it).

The first is with the camera dead level, front-to-back, as indicated by the built-in level gauge. Trees look parallel to me. The second has the camera tilted up a little; the third, a lot. You can see that a bit of tilt has a lot of effect on the trees.

Your trees lean the other way, of course, but I do wonder if you weren't on higher ground -- just a little -- with the camera tilted down. The lakeside shot, in particular, has the horizon WAY up the picture.

So how can you shoot trees like this? 1 -- keep the camera dead horizontal, and then crop the ground out in post. 2 -- get a tilt lens. But those are expensive.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

kghaviland — Mon, 15 Aug 2022 21:04:22 GMT

Thanks to everyone for your comments on this. I think the issue is with the way I am taking the pictures. Just was not used to this type of effect as I have not used a WA lens before. I will pay more attention to leveling the camera and the effect on the image. All of your input is much appreciated!

Re: RF 15-35mm F2.8L IS USM Distortion Issue

kghaviland — Mon, 15 Aug 2022 21:05:26 GMT

Thanks for the very informative input. This is very helpful.

Re: RF 15-35mm F2.8L IS USM Distortion Issue

Edward1064 — Mon, 15 Aug 2022 23:13:24 GMT

Thank you all for your thoughts on this original post. I learned some useful stuff from following the discussion.