rf 15-35MM F2.8L issue? NEED ADVICE!

StevenA

CR Pro
Jul 8, 2020
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So I was out last night making some IBIS stills tests and had on my RF 15-35mm lens. One of the photos I took shows some weird issues I'd like some opinions on:

This is a crop of the image, original was 15mm so this isn't edge of frame stuff. The focal point is somewhere above the right car, on the text in the window - looks fine. But then scan to the left and look at the writing in the window over there. Blurry - why? It's on the same plane as the writing I focused on. Same question on the 'for lease' sign.

0R9A0205small1.jpg

But also - a dead giveaway, look at the rear wheel on the car in the middle of the frame - looks round. Then look at the front wheel on the car immediately behind it. Oval:

0R9A0205small.jpg
full size for reference:

0R9A0205fullsmall.jpg

I know lenses this wide have some issues as you go out from the middle, but these seem excessive? Thoughts?
 

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Aug 27, 2019
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So I was out last night making some IBIS stills tests and had on my RF 15-35mm lens. One of the photos I took shows some weird issues I'd like some opinions on:

View attachment 191928


This is a crop of the image, original was 15mm so this isn't edge of frame stuff. The focal point is somewhere above the middle car, on the text in the window - looks fine. But then scan to the left and look at the writing in the window over there. Blurry - why? It's on the same plane as the writing I focused on. Hard to see in such a small image I know, but also - a dead giveaway, look at the rear wheel on the car in the middle of the frame - looks round. Then look at the front wheel on the car immediately behind it. Oval.

I know lenses this wide have some issues as you go out from the middle, but these seem excessive? Thoughts?
F2.8?

Are you using any of the in camera lens correction?
 
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Two different things.

The writing not being sharp could be a decentered lens element but I doubt it actually is. If you look at the building you are not parallel to it so the windows are not on a flat field parallel to you.

The oval wheel is the result of rectilinear projection distortion and is not a lens defect.
 
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I think I had a similar result in a couple of my earlier shots with 15-35 @15mm F2.8 handheld with slower shutter speeds. Sadly I deleted them as they were not usable. I never ran into any issue with the 15-35 on the R so I am inclined to think it is related to IBIS.

@StevenA this is pure speculation on my part but I think we might be seeing the "jello" effect reported in some videos with the 15-35. I am hoping Canon will be able to tune the IBIS for use with the wider angle lenses.
 
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usern4cr

R5
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Sep 2, 2018
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So I was out last night making some IBIS stills tests and had on my RF 15-35mm lens. One of the photos I took shows some weird issues I'd like some opinions on:

This is a crop of the image, original was 15mm so this isn't edge of frame stuff. The focal point is somewhere above the right car, on the text in the window - looks fine. But then scan to the left and look at the writing in the window over there. Blurry - why? It's on the same plane as the writing I focused on. Same question on the 'for lease' sign.

View attachment 191936

But also - a dead giveaway, look at the rear wheel on the car in the middle of the frame - looks round. Then look at the front wheel on the car immediately behind it. Oval:

View attachment 191937
full size for reference:

View attachment 191935

I know lenses this wide have some issues as you go out from the middle, but these seem excessive? Thoughts?
My answer (aka: "best guess") is that you are *not* on the same image plane regarding the different areas of text you mention - you just "assume" you are.
 
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I think I had a similar result in a couple of my earlier shots with 15-35 @15mm F2.8 handheld with slower shutter speeds. Sadly I deleted them as they were not usable. I never ran into any issue with the 15-35 on the R so I am inclined to think it is related to IBIS.

@StevenA this is pure speculation on my part but I think we might be seeing the "jello" effect reported in some videos with the 15-35. I am hoping Canon will be able to tune the IBIS for use with the wider angle lenses.
Didn't Canon release a firmware update for the RF 15-35, that addresses the 'wobble' / 'jello' ? Do you have the latest firmware on your lens?
 
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Didn't Canon release a firmware update for the RF 15-35, that addresses the 'wobble' / 'jello' ? Do you have the latest firmware on your lens?
Yeah, updated all my RF glass a few days before my R5 showed up. I think the edges @15mm can still be a little lose for longer handheld shots. Once I push to 16mm it is pretty much gone.

IBIS plus super wide seems to be a bit of an issue with all sensor stabilization systems.

Would love to see the results of the 8-15 or the 11-24
 
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StevenA

CR Pro
Jul 8, 2020
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Didn't Canon release a firmware update for the RF 15-35, that addresses the 'wobble' / 'jello' ? Do you have the latest firmware on your lens?

At the time of the photo no, I had not updated to the latest firmware. Stumbled across it yesterday and did the update, but I haven't had a chance to retest and see if it had any effect.
 
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