# Front focusing issue with Canon 50mm f/1.4



## sagittariansrock (May 20, 2014)

I recently decided to upgrade my standard prime 'slightly' by moving from the 50/1.8 to the 50/1.4. I was hoping to use this primarily with my recently purchased 5D.
I bought this used from FredMiranda.com
I am disappointed to see that my 50/1.4 front focuses by almost 1 cm near its MFD with my 5D and slightly less with my 5DIII. I haven't tested all focusing distances yet. 
Now the 5D doesn't have AFMA and focuses perfectly with my 135L. So I don't see the point of messing with its calibration.
At this point, what are my choices?
1. Get rid of the lens? I can't return it as it's not the seller's fault. Is it wrong for me to sell it?
2. Get it calibrated by Canon. Any idea of the cost? It might not be worthwhile if it's costly.
Is this an inherent problem of this lens? Does this signify internal damage due to drops, etc.? 
Any advice will be appreciated.
Thanks


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## sagittariansrock (May 20, 2014)

Any suggestions?


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## Random Orbits (May 20, 2014)

Try evaluating it at different distances and see if you can get an AFMA value that will work over the distance range with the 5DIII. If it can, then the lens is fine, and then you'll have to decide whether or not it's worth calibrating the lens/body (5D) or to use it exclusively on the on 5DIII.

Another question: Are you evaluating it wide open only or stopped down? I never had good luck getting good focus accuracy with the 50 f/1.4 near MFD wide open. Focus accuracy tended to improve at f/2.8 or smaller.


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## ajfotofilmagem (May 20, 2014)

Canon 5D original + 50mm F1.4 is a combination subject to focus problems exactly as you describe. I would not buy lens more luminous than F2.8 to use in a body without AFMA. Assuming you keep the lens exclusively for use on 5D Mark iii, the AFMA setting should be sufficient for accurate auto focus, but even so, the contrast and sharpness in the corners of the image are only decent when stoped down to F2. This lens can create absurdly sharp images at F5.6, but nobody buys F1.4 lens to use with very closed diaphragm. This is one reason that led me to sell my Canon 50mm F1.4.


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## alexturton (May 20, 2014)

use AFMA to correct it.

If you can't correct it in camera send it back to the shop and say it has a manufacturing fault. Ask for a refund or another copy. I've never had any problems in the UK returning lenses with calibration problems.


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## Mt Spokane Photography (May 20, 2014)

Most lenses front focus near MFD, its a accepted fact. The issue is that a wide aperture lens has a very shallow depth of field, so it becomes readily apparent.

Move away from the MFD by a foot or two, and it should be much better.


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## Nitroman (May 20, 2014)

The Canon 50mm f1.2 is even worse and very inconsistent ! Especially at minimum focus distance. All lenses go nuts at this distance as they are calibrated at approx 50x the focal length - 50mm lens x 50 = 2.5m ! 

You need to send it to Canon ... I just had all my lenses and cameras calibrated by Canon Uk. £30 a prime lens, £60 per zoom lens - plus vat.

The 5D is not a good camera to use wide open at f1.4. Even with AFMA, the value changes with distance and light source so it's a real headache. That's why i sent all mine to Canon to be calibrated. 

You also gotta ask yourself how often do you shoot wide open ? And if you can use the 5D3, then i would use it as a preference to the 5D.


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## sagittariansrock (May 20, 2014)

Random orbits:
I hope to use it almost exclusively with the 5D, so even if AFMA works with the 5DIII, it won't be much use. I did take a lot of pictures at smaller apertures (will try to post some in the evening), but they were off focus which made me examine the lens. I tested only wide open because I wanted to see the change in sharpness with a narrow DoF. Anyway, if it doesn't work wide open (not talking about sharpness, soft images are acceptable as long as it focuses on the spot) then there's no use. My 50/1.8 will be fine at f/2 as well, won't it?

AJFoto:
My 135 f/2 and 50/1.8 both focus spot on with the 5D. I think I will have to end up selling it, since I bought it to use with the 5D.

Alex:
Unfortunately, I bought this used from someone in FredMiranda.com. While this ensures good quality and condition through seller reputation, AF calibration isn't something he can be blamed for. It might work perfectly with another camera.

Mt Spokane:
As I mentioned above, the issue was brought to my attention by some real-world shots that were consistently off-focus. These were much farther than MFD. Incidentally, my 135L focuses fine at MFD without any AFMA on either camera I own.

I suppose I have to sell it locally so the buyer can test it with his/her own camera. Sending it in will defeat the financial advantages of buying a used lens.


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## panicboy (May 21, 2014)

I also own a 5d and a 50 1.4 and, while the AF is not very consistent with this camera/lens combo, the inconsistency is somewhat random, i.e. it does not "prefer" to front focus nor to back focus. Plus, I think that it tends to misfocus more often on longer rather than on shorter distances.

These are non-scientific observations, i.e. I did not make any measurements and statistics, just been shooting with the camera/lens combo over the past year or so. In general, I have been pretty happy with the results most of the time.


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## GammyKnee (May 21, 2014)

I you really want to use it mainly with the original 5D then be prepared to go through several copies before you find one that's acceptable wide open at MFD with your body. I totally understand your reticence over sending the lens in for calibration; it's not just the cost but also the fact that it's a gamble. There's always a chance that it'll come back with "in spec, no action required" if you get a lazy / rushed technician.

What's more, you'll still have to deal with a degree of inconsistency from this lens. Mine behaves itself pretty well on my 5D III, but less so on my 5D II (which otherwise focuses very dependably with the center point). I seem to remember reading somewhere that this is to be expected because the AF motor on this lens is only capable of relatively coarse adjustments.

It's shame that 50mm seems to be such a difficult focal length to get right for lens manufacturers. All the Canon offerings have their quirks and issues. The original Sigma 50 had AF issues for many. Only time will tell if the Siggie 50A will be better...


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## sagittariansrock (May 21, 2014)

Thanks for the input panicboy and Gammyknee. I suppose I can live with the lens as long as I can calibrate it in the beginning if necessary. So that 50mm has been sold to a gentleman who tested it with his 70D, and it worked fine. 
I have just purchased another, this time within warranty. So hopefully Canon will calibrate it if it's off.


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## David_in_Seattle (May 22, 2014)

If you hear or feel a slight grinding noise when you turn the manual focus ring then it could be a sign that the mechanism is beginning to fail. The internal focusing mechanism uses one metal and one plastic ring that can get out of alignment by wear and tear with the lens.

I had this issue with 2 copies and when my 3rd one started to mimic the issue I figured I'd try to fix it myself (as I no longer used it as a work lens). I referenced this guide that another Canon Rumor member (Emil) posted back in September:

http://image23photographic.blogspot.no/2012/04/fixing-stuck-focus-ring-on-canon-50mm.html?zx=cc1714b577d841ed


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## Halfrack (May 22, 2014)

sagittariansrock said:


> I have just purchased another, this time within warranty. So hopefully Canon will calibrate it if it's off.


Understand that the lens can only be so calibrated - sending it to Canon will not fix the issue. Your issue is that you need a lens that out of the box works great with your 5D. If you send in your lens and 5d, expect it to screw with your other lenses. This is why the AF microadjustment is such a huge deal - it allows you to adjust how a body uses a lens on a 1:1 basis. The Dof is so small, you've got 1/8" either side of what it thinks is focus, so are you shooting these hand held or?


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## sagittariansrock (May 22, 2014)

Halfrack said:


> sagittariansrock said:
> 
> 
> > I have just purchased another, this time within warranty. So hopefully Canon will calibrate it if it's off.
> ...



Couple of things to note: my 5D works perfectly with my 135L and my 50/1.8II. My (ex) 50/1.4 front focused with both my 5D and my 5DIII. When I described this to the Canon tech he said (and I agree) that the 50/1.4 might need to be calibrated. Even in absence of AFMA, there should be more or less accurate focusing (I tested wide open near MFD, but my real-world shots were at much smaller apertures and longer distances).
Since the errors were systematic and reproducible, it is clear to draw this conclusion.
The attached image was shot hand held at f/4.5 and the focus was on the singer with the blue microphone.
As you will notice the standing silver microphone is in much sharper focus. It is not motion blur because the motion wasn't fast enough to cause blur at 1/60th of a second. You can see some of the singers in the same plane as the silver microphone are sharply focused.




David_in_Seattle said:


> I had this issue with 2 copies and when my 3rd one started to mimic the issue I figured I'd try to fix it myself (as I no longer used it as a work lens). I referenced this guide that another Canon Rumor member (Emil) posted back in September:
> 
> http://image23photographic.blogspot.no/2012/04/fixing-stuck-focus-ring-on-canon-50mm.html?zx=cc1714b577d841ed





Thanks for the information, David!


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