Focal Length problem with EF 70-300mm f/4-5.6 IS II USM - shows up as 267mm

[MickKazik]

Hi everyone, I just received my new EF 70-300mm f/4-5.6 IS II USM and I'm battling a big issue.

On its long end (supposedly 300mm), the zoom ring rotates all the way but lens indicate 267mm in the photo data (Canon 200D). Since it has got an APS-C sensor, the display on the lens should indicate 480mm. In reality the marker on the lens is lined up at 300mm but on the built in lens display if falls a quarter of an inch short.

On my ancient 1D mk II n the indicator on the display should point to 390mm but falls short again. 

In both cases only the shorter focal length of 70mm is lined up properly and also shows as 70mm in photo info.

Both in-camera info and Lightroom EXIF data indicate incorrect values. Basicaly, the longer you extend, the bigger the discrepancy. Example:

70mm = 70mm

100mm = 94mm

135mm = 126mm

200mm = 176mm

300mm = 267mm

Do you think I can do anything with it or did I get a faulty piece?

Thanks in advance!

[ebiggs1]

I understand but at the very first of this issue, if you, the OP, anybody, is using LR or EXIF to verify your lens is actually what it claims, you can't do that with any expectation of accuracy. And that is exactly what he noticed and asked. Correct?

Also I have no way of knowing any new posters level of photographic knowledge. Most of the regulars here are advanced but lots of new posters are not. That is where you begin. The first screen shot was apparently a macro shot so focus breathing had to be examined.  He also was using EXIF data to confirm the FL. That was the start but now we all know differently and believe the lens is truly faulty and needs to be returned.

Perhaps sloppily but everyone is trying to help. Even me! 

[MickKazik]

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@ebiggs1 wrote:

"...what gave you an impression I may have assumed 480mm marking would give me 480mm?"

The "impression" was if you expected LR to report the exact FL you may be disappointed. The 70-300mm zoom lens may not be capable of 300mm even on a perfectly working lens. LR may still report that it is at 300mm although it is impossible for the lens to reach 300mm.

Exactly! LR may still report 300mm - but it doesn't! At no stage the 'true', 'exact' or 'real life' FL was even brought into the conversation other than by yourself. Other contributors seemed the understand LR and in-camera EXIF data should report what's on the barrel. And if that reported FL is an actual true FL well, God only knows.

Your comment about the 480mm is still a mystery to me. 480mm on a 300mm lens? I'm a hobbyst but come on...

[MickKazik]

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@wq9nsc wrote:

Mick,

Glad to hear that you are returning it.  It does sound like it was probably a defective return and sometimes retail distributors just put a returned item back into distribution even though they shouldn't.  I buy a fair amount through Amazon and twice I have received "new" items that clearly weren't but at least the return process was very easy.

I haven't done extensive testing but in a quick test with my Canon EF 70-200 f2.8 and EF 24-70 f2.8 lenses, both indicate the correct focal length at both zoom extremes regardless of focus distance from minimum focus distance to infinity.  I suspect that the zoom mechanism feeds the commanded focal length data which may not be exact for the actual focus length but the numbers will be invariant with respect to focus distance. 

Rodger

Hi Rodger! Thanks a lot for your response and testing done. You understood the problem prefectly, I wish there was some easy solution to it, re-calibrating of some sorts. There is no problem with returning it though, it will go back tomorrow. 

Nevertheless, I was astounded by the lack of of info online about the exact issue with this lens. Surely I'm not the only one with this kind of defect (statement in advance: no it is not focus breathing). Thanks again.

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[MickKazik]

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@Waddizzle wrote:

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@MickKazik wrote:

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@Waddizzle wrote:

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@MickKazik wrote:

I brought it up with regards to your previous statement Waddizzle:

"It would be wise to completely ignore what results you see with this lens mount adapter when used with an APS-C body".

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???  So, why bring it up again.  It is not even an adapter for a Canon camera. ???  My advice was to ignore it.  ???

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Maybe I should explain why I made a reference to your point about the adapter (again...).

You probably recognised by now you made a mistake with regards to an APS-C adapter on a Canon SL2. Canon SL2 doe's not require an adapter, it accepts both EF and EF-S lenses. 

Canon 1D mk II n accepts EF lenses.

Fuji Adapter only confirmed the flaw, the issue persisted in the same manner so I really beg to differ - you do not ignore something that gives you an accurate confirmation of the defect. 

I appreciate you trying to help out anyway. Regards!

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Make no mistake. I did not make a mistake.  I immediately dismissed it.  

The only mistake is your continuing to beat this dead horse.  How poorly that Fuji adapter performs is totally irrelevant.  It is not Canon gear.  If the adapter does not work well with some Canon gear, so what.  It does not mean the Canon gear is bad.  I really do not know or care what it might mean.

The only real test that matters is testing Canon gear with Canon gear.  As for your focal length display issue, I think that it is probably a non-issue.  What might be your issue is discussed beginning around the #:30 mark in this video by Tony Northrup.

https://youtu.be/bfhudi0d-go 

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Unfortunatelly I must beat this dead horse for as long as you provide inaccurate into. This adapter does not perform poorly - the lens does. 

I used all I have in my arsenal in order to establish / prove or eliminate cause of the problem. The adapter performance is in line with native Canon cameras. It indicated the same flaw based on the 300mm reading (as it is not recognised as crop factor by the lens). 

So please tell me, if the adapter provided accurate readings and data export, would you still say it's irrelevent? Would your problem diagnosis remain the same? If the outcome from Canon native gear was contradicting the data from the adapter would you still stand by your original diagnosis (at this stage you must see it's not focus breathing) or would you look somewhere else? 

[Waddizzle]

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@jrhoffman75 wrote:
Does anyone here, besides Mick and myself, actually own the lens?

The lens reports 70-300 on my 1D X and 112 to 480 (stating 35mm equivalent) on my wife’s Rebel T6s crop sensor.

Lens appears to be defective.

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I agree.  I think the lens is defective, too.  The very first thing I advised was to return it for a full refund.  I learned that it is a used lens, and added the caveat to find a new vendor, no exchanges.

[Waddizzle]

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@MickKazik wrote:

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@Waddizzle wrote:

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@MickKazik wrote:

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@Waddizzle wrote:

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@MickKazik wrote:

I brought it up with regards to your previous statement Waddizzle:

"It would be wise to completely ignore what results you see with this lens mount adapter when used with an APS-C body".

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???  So, why bring it up again.  It is not even an adapter for a Canon camera. ???  My advice was to ignore it.  ???

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Maybe I should explain why I made a reference to your point about the adapter (again...).

You probably recognised by now you made a mistake with regards to an APS-C adapter on a Canon SL2. Canon SL2 doe's not require an adapter, it accepts both EF and EF-S lenses. 

Canon 1D mk II n accepts EF lenses.

Fuji Adapter only confirmed the flaw, the issue persisted in the same manner so I really beg to differ - you do not ignore something that gives you an accurate confirmation of the defect. 

I appreciate you trying to help out anyway. Regards!

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Make no mistake. I did not make a mistake.  I immediately dismissed it.  

The only mistake is your continuing to beat this dead horse.  How poorly that Fuji adapter performs is totally irrelevant.  It is not Canon gear.  If the adapter does not work well with some Canon gear, so what.  It does not mean the Canon gear is bad.  I really do not know or care what it might mean.

The only real test that matters is testing Canon gear with Canon gear.  As for your focal length display issue, I think that it is probably a non-issue.  What might be your issue is discussed beginning around the #:30 mark in this video by Tony Northrup.

https://youtu.be/bfhudi0d-go 

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Unfortunatelly I must beat this dead horse for as long as you provide inaccurate into. This adapter does not perform poorly - the lens does. 

I used all I have in my arsenal in order to establish / prove or eliminate cause of the problem. The adapter performance is in line with native Canon cameras. It indicated the same flaw based on the 300mm reading (as it is not recognised as crop factor by the lens). 

So please tell me, if the adapter provided accurate readings and data export, would you still say it's irrelevent? Would your problem diagnosis remain the same? If the outcome from Canon native gear was contradicting the data from the adapter would you still stand by your original diagnosis (at this stage you must see it's not focus breathing) or would you look somewhere else? 

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My first advice to you was to return it for a ful refund.  My second advice was to find a new vendor.  Good Luck.

[ebiggs1]

It seems you have taken a negative view of my remarks so after this further attempt to clarify it, I will bow out of the  conversation. I hope you get it resolved to your satisfaction. As I repeatedly said all of us are only trying to help. Some wanted perhaps and some not but that's he way it is when you ask for advice.

" 'ebiggs1' could you clarify what gave you an impression I may have assumed 480mm marking would give me 480mm? Or are you just saying it for the sake of it?"

This was a simplr question!

"BTW, you do understand the 480 'number' that is indicated in the window is not and does not confirm you have a 480mm lens?"

From a post.............

It is pretty common for some especially new people to assume the lens changes it FL when mounted to a crop body camera.  Canon, and others, probably don't help by doing stuff like this example. It confuses  people all the time. 

The correct response to me should have been, "Yes I know that". But whatever, I hope you get it sorted soon.

BTW, waddizle, although he and I disagree a lot of the time, has a point about the adapter. He's not too good at expressing it amicably but apparently neither am I. Good luck.

[kvbarkley]

I do, it reports 112-480 on its LCD on my Rebel T6S. And the EXIF shows 300 mm

[MickKazik]

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@ebiggs1 wrote:

It seems you have taken a negative view of my remarks so after this further attempt to clarify it, I will bow out of the  conversation. I hope you get it resolved to your satisfaction. As I repeatedly said all of us are only trying to help. Some wanted perhaps and some not but that's he way it is when you ask for advice.

" 'ebiggs1' could you clarify what gave you an impression I may have assumed 480mm marking would give me 480mm? Or are you just saying it for the sake of it?"

This was a simplr question!

"BTW, you do understand the 480 'number' that is indicated in the window is not and does not confirm you have a 480mm lens?"

From a post.............

It is pretty common for some especially new people to assume the lens changes it FL when mounted to a crop body camera.  Canon, and others, probably don't help by doing stuff like this example. It confuses  people all the time. 

The correct response to me should have been, "Yes I know that". But whatever, I hope you get it sorted soon.

BTW, waddizle, although he and I disagree a lot of the time, has a point about the adapter. He's not too good at expressing it amicably but apparently neither am I. Good luck.

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You are right though, I did take a negative view of some of your responses and I will tell you why. 

It seemed to me your comments were drifting away from the real issue and towards finding problems where there there are none. The way you phrased your 'questions' didn't strike me as genuine pursuit for answers related to the topic. And lastly, if you actualy pay attention to expressing yourself amicably, remarks such as: "The correct response to me should have been, "Yes I know that"." is definitely not the way.

Let me be clear, I do appreciate you trying to help. Especially that you, and every other member here does it voluntairly. You might agree with me though that commenting without encountering similar problem in the past, full understanding of the issue or veering off-topic may sometimes be confusing. 

Long story short, all we established is that the lens is faulty and should be returned. I would've hoped Canon Community would be able to shed some light with regards to potential cause of this issue / repair options. This is purely my curiosity at this stage. 

Anyway, thanks again for your contribution and I wish you all the best!

[MickKazik]

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@kvbarkley wrote:

I do, it reports 112-480 on its LCD on my Rebel T6S. And the EXIF shows 300 mm

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Thanks a lot for sending it on! Much appreciated! Wanna swap lenses?;) It's a lovely piece, happy shooting!