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!

[jrhoffman75]

Since you say you just received it return to vendor and exchange for new item.

[Waddizzle]

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@MickKazik wrote:

Hey 'ebigs', thanks for your insight. It's certainly good to know that going forward, I wasn't even aware of it but unfortunatelly it doesn't seem this to be the case here.

The lens was bought on Amazon and in 'excellent condition'. I am suspecting it could've been a return due to the same issue that was never resolved.

Any other ideas taking into account all of the above would be much appreciated.

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

If you are suggesting that you bought a used lens, return it without further delay for a full refund.  Buy a new one from Canon, which has full one year warranty.

[MickKazik]

Hi Waddizzle, as you said it is best to ask for refund / replacement. 

The lens was bought off Amazon Italy (warehouse) as "excellent condition" item, specifically an "open box, missing papers" kind of thing. It's unacceptable that is is in fact faulty. 

Just to clarify, the adapter was used only with Fujifilm XT3 in order to confirm the issue. As you can see, it is not the fault of the adapter (best there is for Fuji - Fringer EF - FX Pro II). All photos and data used came from the lens itself and also Canon 200D (SL2) - there should be no issues there. 

My 1D mk II n is a 1.3x crop camera that only accepts EF lenses - the issue remains. 

It's just such a pitty and 1st time I came across something like this. Thanks everyone for all the info, much appreciated!

If anyone knows how this could happen with a brand new lens please let me know.

[Waddizzle]

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@MickKazik wrote:

Hi Waddizzle, as you said it is best to ask for refund / replacement. 

The lens was bought off Amazon Italy (warehouse) as "excellent condition" item, specifically an "open box, missing papers" kind of thing. It's unacceptable that is is in fact faulty. 

Just to clarify, the adapter was used only with Fujifilm XT3 in order to confirm the issue. As you can see, it is not the fault of the adapter (best there is for Fuji - Fringer EF - FX Pro II). All photos and data used came from the lens itself and also Canon 200D (SL2) - there should be no issues there. 

My 1D mk II n is a 1.3x crop camera that only accepts EF lenses - the issue remains. 

It's just such a pitty and 1st time I came across something like this. Thanks everyone for all the info, much appreciated!

If anyone knows how this could happen with a brand new lens please let me know.

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You should return the camera lens for a full refund, and find a new vendor.  

Your Fuji mount adapter is of no concern to me.  I do not understand why you even brought it up.  If the Canon lens does not work with Fuji camera using an adapter, then that is of no concern to me.  Visit a Fuji forum for help with it.

If the issue is present with a different Canon body, then return the lens.  The vendor is unreliable.  Take your money and shop with another vendor.  I recommend Canon directly.  They're reliable.

[MickKazik]

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".

[shadowsports]

Maybe test it on another body.  I'm on FF.  I wouldn't trust a non canon adapter.  300mm is possible.

  

[MickKazik]

Thanks for the photo Rick and confirming 300mm should be possible.

As previously mentioned, the lens was originally tested on Canon SL2 and Canon 1D mk II n. That's 3 cameras in total, same issue. It will be going back.

[ebiggs1]

"... return to vendor and exchange for new item."

1+

[ebiggs1]

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

Sometimes these less expensive zoom lenses can get unconnected from their internals. There is a procedure to correct this on the notoriously prone ef-s 18-55mm kit lens. I don't know if it works on your zoom however.

I also don't know if this lens reports accurately to Lightroom about FL when focus breathing is involved. Sometimes lenses will  lie to the camera and LR will read that.  

[Waddizzle]

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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.  ???

I think I should have explained why I mentioned APS-C body.  I had incorrectly assumed that you were using a Canon mirrorless body.  The EF and EF-S mounts are physically different.

Nearly all lens adapters made for  Canon EF mount lenses are always EF mount,and never EF-S mount.  This means if you use the adapter with EF-S lens, the host body normally will not know that you are using a an EF-S mount lens.  The Canon RF adapters for EF/EF-S mount lenses seem able to detect the different lenses, and transmit this info to the camera body.

In other words, if the focal length is being reported incorrectly for an APS-C body, then ignore the apparent mistake because that is how the adapter is designed to function.