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Does / did your 50L backfocus and what happened?
Bought one, love it, no problems PollPollPoll 19 4%
Bought it, no problems, but not that impressed PollPollPoll 6 1%
Mine had the focus problem, I returned / sold it PollPollPoll 15 3%
Mine had the focus problem, but it was possible to sort it PollPollPoll 6 1%
I would have bought one but am waiting because of the focus problem PollPollPoll 41 9%
Just show results PollPollPoll 391 82%
Total Votes 478 100%

Archive 2007 · Where are we with the 50L?

  
 
stanj
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p.2 #1 · Where are we with the 50L?


Very interesting, thank you. I'll wait


Jun 26, 2007 at 02:03 AM
Lord Fluff
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p.2 #2 · Where are we with the 50L?


What I cannot get my head around is that Canon can design a pin-sharp 1.2 85mm lens some years back, then end up with a seemingly flawed design for what should be an easier focal length to build anyway. I appreciate that some people are learning ways to get round the problem, but this just seems amazing when I never have to doubt the behaviour of my 85L (and if I did it would be swapped for the 1.8)


Jun 26, 2007 at 03:22 PM
Harvey Moore
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p.2 #3 · Where are we with the 50L?


Chuck Westfall sent me an e-mail reply over a month ago indicating that that Canon is indeed looking into the 50L focus issue.

The hope from me is that the 1DIII problem(s) have not put the 50L issue on the back burner.

I am impressed with my 50L with exception of close focus problem.



Jun 26, 2007 at 04:00 PM
SoundHound
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p.2 #4 · Where are we with the 50L?


There are focus issues with the 85L too-different issues. Just like the 85L this is a speciality lens although appearing to be general purpose FL lens. The extra bux are spent for the F1.2-F2.0 range and, at least one poster, thinks it focuses well here. There are always focus problems/considerations with narrow depth of field.

If you are using a FF body (and many are since this is such an expensive lens) the 50mm FL has never been a show stopper. Indeed in the old (FF) Film days the 50mm was the "Kit Lens" that you put into the drawer after the other, prime, lenses were bought (the zooms were few and NSG).

Adding to the problem is that Canon charges so much money for that extra 1.2 F stop while the deluxe L build makes it larger and heavier. Size that is, apparently, wasted since the objective lens is so small in relation to the diameter of the lens. Now that I am using the 1.3x crop of the MkIII the FL is between my favorite FL so it stays in the drawer.

With all of that I am still amazed that Canon can't make a, mature design, 50mm F1.2 lens with all their experience and why it has to cost so much.






Jun 27, 2007 at 02:18 PM
mh2000
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p.2 #5 · Where are we with the 50L?


I for one am looking to buy one for better performance and bokeh at f2 and above. Castleman demenstrates the focus issue at f4 (yikes!). I shoot almost everything with the problem zone.

For me, the "kit lens" stayed on my camera and I kept a few other lenses in my drawer for those very rare shots that didn't call for a fast 50



Jun 27, 2007 at 02:34 PM
ansye
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p.2 #6 · Where are we with the 50L?


I got my 50L and I am still looking for the issue people are talking about. I haven't encounter any issues taking pictures close and far and with abundant light as well as dark kitchen etc. How do I make sure that my copy is indeed not suffer from this issue, or otherwise?

thank you
ansye



Jun 27, 2007 at 03:03 PM
Roy Pertchik
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p.2 #7 · Where are we with the 50L?


I e-mailed a Canon insider and learned that there is no new word from Canon since a month ago when they said to expect a public announcement. He recommended:

.... contact our Customer Support Center directly if you wish to pursue the matter:

* E-Mail: Send an email to [email protected].

* Telephone: Call Canon’s Customer Support Center toll-free at 1-800-828-4040. Kindly provide the service representative with your contact information, your EF 50mm f/1.2L USM serial number, and details about the focusing issues you are experiencing.



Sounds like it would be productive to remind Canon that there are Canon users who would like to hear a statement.



Jun 27, 2007 at 06:06 PM
cactusclay
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p.2 #8 · Where are we with the 50L?


ansye wrote:
I got my 50L and I am still looking for the issue people are talking about. I haven't encounter any issues taking pictures close and far and with abundant light as well as dark kitchen etc. How do I make sure that my copy is indeed not suffer from this issue, or otherwise?

thank you
ansye

Try taking a head shot of someone at about three and a half feet away. Focus on their eyes or one eye at F4. If the nose looks shaper than the eye, you may have a problem, or shoot the eye at 1.2 to 2.0 and see if that is sharper than the F4 shot is. Or, you can shoot a ruler or one of the test charts



Jun 27, 2007 at 07:09 PM
tmr4
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p.2 #9 · Where are we with the 50L?


cactusclay wrote:
Try taking a head shot of someone at about three and a half feet away. Focus on their eyes or one eye at F4. If the nose looks shaper than the eye, you may have a problem, or shoot the eye at 1.2 to 2.0 and see if that is sharper than the F4 shot is. Or, you can shoot a ruler or one of the test charts


The second test, see if the wide open shot is sharper than one stopped down, is the test. The first would be ok for a face shot at an angle.

Here is a crop of the problem I posted earlier in the thread:

https://www.fredmiranda.com/forum/topic/547792/2#4761537

and a link to my tests:

http://www.pbase.com/tmr4/distance_test



Jun 28, 2007 at 11:34 PM
jm42
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p.2 #10 · Where are we with the 50L?


I have seen posts suggesting that there is no focusing problem with the XTi. However, they did not elaborate. And if the problem is focus shift I cannot really see how the XTi could be more successful.
Still, this is high-tech world and almost anything is possible, and clearing the 50L for use with my XTi would be wonderful, so I thought I should take the opportunity to try to get a more definite comment on the subject.
Anyone..?

(Could it be so easy that you are further away when you are shooting with a crop body? I.e. less likely to be within 5 feet.)



Jul 01, 2007 at 05:50 AM
tmr4
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p.2 #11 · Where are we with the 50L?


jm42 wrote:
I have seen posts suggesting that there is no focusing problem with the XTi. However, they did not elaborate. And if the problem is focus shift I cannot really see how the XTi could be more successful.
Still, this is high-tech world and almost anything is possible, and clearing the 50L for use with my XTi would be wonderful, so I thought I should take the opportunity to try to get a more definite comment on the subject.
Anyone..?

(Could it be so easy that you are further away when you are shooting with a crop body? I.e. less likely to be
...Show more

I shoot with the XTi and it has the problem within 3 feet or so. I've posted links to my test shots in the post above this.



Jul 01, 2007 at 06:18 PM
mbailey
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p.2 #12 · Where are we with the 50L?


tmr4 wrote:
I shoot with the XTi and it has the problem within 3 feet or so. I've posted links to my test shots in the post above this.


I can demonstrate the problem with my 5D using the center focus point but not using the minor focus points. I could not get my XT to show the problem at all. This made me think that the f/2.8 sensitive points had the issue.



Jul 01, 2007 at 10:33 PM
jm42
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p.2 #13 · Where are we with the 50L?


tmr4, one couldn’t possibly get a better analysis of the subject. The effort you have put into the test is highly appreciated!
I guess the only way to overcome the reported discrepancy between chart and real-life results is by trying the lens yourself.

Thanks both of you for your comments!



Jul 02, 2007 at 04:17 PM
zhangp
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p.2 #14 · Where are we with the 50L?


Roy Pertchik wrote:
I e-mailed a Canon insider and learned that there is no new word from Canon since a month ago when they said to expect a public announcement. He recommended:

.... contact our Customer Support Center directly if you wish to pursue the matter:

* E-Mail: Send an email to [email protected].

* Telephone: Call Canon’s Customer Support Center toll-free at 1-800-828-4040. Kindly provide the service representative with your contact information, your EF 50mm f/1.2L USM serial number, and details about the focusing issues you are experiencing.

Sounds like it would be productive to remind Canon that there are Canon users who would
...Show more

Any update?



Jul 03, 2007 at 08:58 PM
tmr4
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p.2 #15 · Where are we with the 50L?


mbailey wrote:
I can demonstrate the problem with my 5D using the center focus point but not using the minor focus points. I could not get my XT to show the problem at all. This made me think that the f/2.8 sensitive points had the issue.


Very interesting. I recall that you mentioned the XT result before. I also had much better performance using the outer focus points with my XTi and I was speculating that it was a result of some differential masking of problematic light rays before they got to the AF sensor.

Don't some bodies have non-center f/2.8 points. If so it be interesting to see if using them resolves the issue also. If not then that would bump it up as a cause. Not quite sure why it would work that way though, perhaps a problem with the software.



Jul 03, 2007 at 10:26 PM
Gochugogi
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p.2 #16 · Where are we with the 50L?


Don't some bodies have non-center f/2.8 points. If so it be interesting to see if using them resolves the issue also. If not then that would bump it up as a cause. Not quite sure why it would work that way though, perhaps a problem with the software.

Yep, the EOS 3, 1V and all the 1D series sport a cluster of 7 F2.8 cross sensors. The MK3 has even more...



Jul 03, 2007 at 11:52 PM
mh2000
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p.2 #17 · Where are we with the 50L?


>>and a link to my tests:

http://www.pbase.com/tmr4/distance_test

curious... how is backfocus supposed to work in manual focus?? Your eye *should* be seeing the same thing that your sensor will see... so how is your eye being tricked? I can only image that either your eyes are faulty or your camera is not properly calibrated. AF is of course what it is...



Jul 04, 2007 at 02:02 AM
John P Mulgrew
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p.2 #18 · Where are we with the 50L?


Got the lens but never used it above f/2. Got other lenses for that


Jul 04, 2007 at 05:58 AM
johnastovall
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p.2 #19 · Where are we with the 50L?


I'm sticking with my 50/1.0.


Jul 04, 2007 at 11:21 AM
tmr4
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p.2 #20 · Where are we with the 50L?


mh2000 wrote:
>>and a link to my tests:

http://www.pbase.com/tmr4/distance_test

curious... how is backfocus supposed to work in manual focus?? Your eye *should* be seeing the same thing that your sensor will see... so how is your eye being tricked? I can only image that either your eyes are faulty or your camera is not properly calibrated. AF is of course what it is...


Sorry, probably using the term manual focus loosely here. Yes my eyes aren't great so for the manual focus shots I did trial shots with manual focus until I got best focus on review at 100%. The difference from the AF setting was very tiny and totaly indistiguishable, to me at least, in the viewfinder. To do better than this I'd need a better focus screen.



Jul 04, 2007 at 11:35 AM
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