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Archive 2009Explain the 50mm L problem
p.2 #1Explain the 50mm L problem
Does the Canon 50mm f1.4 suffer from focus shift?
Mar 18, 2009 at 01:06 PM
p.2 #3Explain the 50mm L problem
I don't understand it when people say that the issue is blown out of proportion. It's a major design flaw characteristic in a $1400 'L'uxury lens....what exactly do you expect? If you buy the lens to use only at f/1.8 and wider and f/8 and narrower or at a distance of +6ft then that's great--but what about those who want use it close to mfd (6ft or less) at f/2-f/5.6? I've always been intrigued by this lens, and more recently the sigma 1.4, but the focus shift/AF issues have staved me off every single time I get close to buying one. BTW I have used various copies of this lens, while not extensively, on multiple occasions as well as the Sigma (only one copy) so I can say I do have first hand experience with the issue(s). Yohan, I should have just '+1'ed your post 
Mar 18, 2009 at 01:12 PM
p.2 #4Explain the 50mm L problem
kahren wrote:
isn't the 50L a tilt shift lens?
No... Canon EF 50/1,2L USM is not a TS-E
isn't the 50L a tilt shift lens?
No... Canon EF 50/1,2L USM is not a TS-E
Mar 18, 2009 at 01:21 PM
p.2 #5Explain the 50mm L problem
David Baldwin wrote:
Does the Canon 50mm f1.4 suffer from focus shift?
Nope.
Does the Canon 50mm f1.4 suffer from focus shift?
Nope.
Mar 18, 2009 at 01:21 PM
p.2 #6Explain the 50mm L problem
+1
M Vers wrote:
I don't understand it when people say that the issue is blown out of proportion. It's a major design flaw characteristic in a $1400 'L'uxury lens....what exactly do you expect? If you buy the lens to use only at f/1.8 and wider and f/8 and narrower or at a distance of +6ft then that's great--but what about those who want use it close to mfd (6ft or less) at f/2-f/5.6? I've always been intrigued by this lens, and more recently the sigma 1.4, but the focus shift/AF issues have staved me off every single time I get close to...Show more →
M Vers wrote:
I don't understand it when people say that the issue is blown out of proportion. It's a major design flaw characteristic in a $1400 'L'uxury lens....what exactly do you expect? If you buy the lens to use only at f/1.8 and wider and f/8 and narrower or at a distance of +6ft then that's great--but what about those who want use it close to mfd (6ft or less) at f/2-f/5.6? I've always been intrigued by this lens, and more recently the sigma 1.4, but the focus shift/AF issues have staved me off every single time I get close to...Show more →
Mar 18, 2009 at 01:29 PM
p.2 #7Explain the 50mm L problem
Are you telling me that all of us don't shoot the exact same thing and that "real world" shooting doesn't mean exactly the same thing for all of us? Shocking news...;-)
I agree with you 100%.
I don't understand it either. You can certainly understand folks being defensive about gear they own, and the fact is I own this lens, and kept this lens, so I must like it as some level. I do. It can be a fantastic lens if you know it's shortcomings, and know how to work around them.
Having owned or tested 5 or 6 of these, this is my take on the 50L.
Shooting close quarters is not its strength. This means MFD to perhaps 4-6 feet out. This is where all the bad stuff happens. Wide open, there is no shift, but there's the "ghosting" effect until about f1.8. By f2.0 things are nice and sharp but then you have to worry about the focus shift. Now I've used pretty bad copies of this lens that even at f8, the DOF isn't wide enough to cover it up. Doh!
If shooting at 4-6 feet is real world shooting to you, I would seriously think twice before plunking down the money for this lens.
Otherwise, you are golden.
M Vers wrote:
I don't understand it when people say that the issue is blown out of proportion. It's a major design flaw characteristic in a $1400 'L'uxury lens....what exactly do you expect? If you buy the lens to use only at f/1.8 and wider and f/8 and narrower or at a distance of +6ft then that's great--but what about those who want use it close to mfd (6ft or less) at f/2-f/5.6? I've always been intrigued by this lens, and more recently the sigma 1.4, but the focus shift/AF issues have staved me off every single time I get close to...Show more →
I agree with you 100%.
I don't understand it either. You can certainly understand folks being defensive about gear they own, and the fact is I own this lens, and kept this lens, so I must like it as some level. I do. It can be a fantastic lens if you know it's shortcomings, and know how to work around them.
Having owned or tested 5 or 6 of these, this is my take on the 50L.
Shooting close quarters is not its strength. This means MFD to perhaps 4-6 feet out. This is where all the bad stuff happens. Wide open, there is no shift, but there's the "ghosting" effect until about f1.8. By f2.0 things are nice and sharp but then you have to worry about the focus shift. Now I've used pretty bad copies of this lens that even at f8, the DOF isn't wide enough to cover it up. Doh!
If shooting at 4-6 feet is real world shooting to you, I would seriously think twice before plunking down the money for this lens.
Otherwise, you are golden.
M Vers wrote:
I don't understand it when people say that the issue is blown out of proportion. It's a major design flaw characteristic in a $1400 'L'uxury lens....what exactly do you expect? If you buy the lens to use only at f/1.8 and wider and f/8 and narrower or at a distance of +6ft then that's great--but what about those who want use it close to mfd (6ft or less) at f/2-f/5.6? I've always been intrigued by this lens, and more recently the sigma 1.4, but the focus shift/AF issues have staved me off every single time I get close to...Show more →
Mar 18, 2009 at 01:54 PM
p.2 #8Explain the 50mm L problem
One more thing I neglected to point out in my initial post....I'd rather pay $300 for a lower quality built lens that produces borderline 'inferior' results at a one stop loss than $1400 for a lens with said restrictions. I'm not saying the lens isn't worth it in general, it's just not worth it to me.
Mar 18, 2009 at 02:03 PM
p.2 #9Explain the 50mm L problem
M Vers wrote:
One more thing I neglected to point out in my initial post....I'd rather pay $300 for a lower quality built lens that produces borderline 'inferior' results at a one stop loss than $1400 for a lens with said restrictions. I'm not saying the lens isn't worth it in general, it's just not worth it to me.
Indeed, Im selling my L and already got adapter and 50/1.2AIS Nikkor coming. 50L is easily the biggest disappointment of the 15 EF lenses I have/have had.
One more thing I neglected to point out in my initial post....I'd rather pay $300 for a lower quality built lens that produces borderline 'inferior' results at a one stop loss than $1400 for a lens with said restrictions. I'm not saying the lens isn't worth it in general, it's just not worth it to me.
Indeed, Im selling my L and already got adapter and 50/1.2AIS Nikkor coming. 50L is easily the biggest disappointment of the 15 EF lenses I have/have had.
Mar 18, 2009 at 02:09 PM
p.2 #11Explain the 50mm L problem
This is more addressed to people that have experienced the focus shift in this lens - Is there a pattern to the focus shift, meaning does it shift focus to the rear of the focus plane or is that inconsistent? If it is consistent, does the shift amount change proportionally to the aperture value used? Meaning did you guys noticed more of a focus shift using f/5.6 than using f/4.0, for example?
Thanks,
Joshua
Thanks,
Joshua
Mar 18, 2009 at 02:12 PM
p.2 #12Explain the 50mm L problem
Nick Nishizaka wrote:
Stop the propaganda you two!
No propaganda here, Nick. I want to love the lens, I really do...it offers things my 50/1.4 doesn't (namely L BQ and more importantly f/1.2) but it's unreliability is a major killer for me. The 50L is kinda like a hot chick with a lazy eye or a conspicuous reoccurring "cold sore"--it only takes one major flaw, even though others can overlook it, to turn me completely off.
p.s. I apologize to those with lazy eyes and or herpes. Condolences.
Stop the propaganda you two!
No propaganda here, Nick. I want to love the lens, I really do...it offers things my 50/1.4 doesn't (namely L BQ and more importantly f/1.2) but it's unreliability is a major killer for me. The 50L is kinda like a hot chick with a lazy eye or a conspicuous reoccurring "cold sore"--it only takes one major flaw, even though others can overlook it, to turn me completely off.
p.s. I apologize to those with lazy eyes and or herpes. Condolences.
Mar 18, 2009 at 02:22 PM
p.2 #13Explain the 50mm L problem
AGeoJO wrote:
This is more addressed to people that have experienced the focus shift in this lens - Is there a pattern to the focus shift, meaning does it shift focus to the rear of the focus plane or is that inconsistent? If it is consistent, does the shift amount change proportionally to the aperture value used? Meaning did you guys noticed more of a focus shift using f/5.6 than using f/4.0, for example?
Thanks,
Joshua
The focus shift is proportionately greater at closer focusing distances and at physically smaller apertures. In the second case, however, depth of field increases more rapidly as you stop down than the focus shift does. So, if you are focusing at 4 feet, by the time you reach f/5.6, the DOF will extend inward more than enough to compensate for the focus shift (which is always outward as you stop down).
At the minimum focusing distance of 18", the focus shift could be a real pain at f/2.8 or f/4. It really becomes a question of how you use the lens. Want to shoot a wedding ring from MFD at f/2.8 so you get a little more range of sharp focus than at 1.2 but still blur the background to oblivion? You might have to play with the focus a bit. Shooting portraits from 4 to 10 feet (I don't like the perspective of portraits from 3 feet, but tastes change...)? Don't worry about the 50L. Shoot it wide open for a look that's hard to get otherwise, shoot at 2.8 for two people who are almost but not quite same distance away, stop down to f/8 for a tack sharp group, etc. It will not be a problem. Shooting wide open, the accuracy of the off center points on a 1D series is helpful.
If you've ever fought the flare and ghosting of a heavily backlit shot with, say, a 50/1.4, you'll love how well the 1.2L handles that. Horses for courses.
This is more addressed to people that have experienced the focus shift in this lens - Is there a pattern to the focus shift, meaning does it shift focus to the rear of the focus plane or is that inconsistent? If it is consistent, does the shift amount change proportionally to the aperture value used? Meaning did you guys noticed more of a focus shift using f/5.6 than using f/4.0, for example?
Thanks,
Joshua
The focus shift is proportionately greater at closer focusing distances and at physically smaller apertures. In the second case, however, depth of field increases more rapidly as you stop down than the focus shift does. So, if you are focusing at 4 feet, by the time you reach f/5.6, the DOF will extend inward more than enough to compensate for the focus shift (which is always outward as you stop down).
At the minimum focusing distance of 18", the focus shift could be a real pain at f/2.8 or f/4. It really becomes a question of how you use the lens. Want to shoot a wedding ring from MFD at f/2.8 so you get a little more range of sharp focus than at 1.2 but still blur the background to oblivion? You might have to play with the focus a bit. Shooting portraits from 4 to 10 feet (I don't like the perspective of portraits from 3 feet, but tastes change...)? Don't worry about the 50L. Shoot it wide open for a look that's hard to get otherwise, shoot at 2.8 for two people who are almost but not quite same distance away, stop down to f/8 for a tack sharp group, etc. It will not be a problem. Shooting wide open, the accuracy of the off center points on a 1D series is helpful.
If you've ever fought the flare and ghosting of a heavily backlit shot with, say, a 50/1.4, you'll love how well the 1.2L handles that. Horses for courses.
Mar 18, 2009 at 02:34 PM
p.2 #14Explain the 50mm L problem
From my experiences, as you stop down from f2 to f5.6 for example, the focus plane progressively shifts towards the rear.
The amount of shift also varies by copy. My old copy that Canon took shifted even at 6ft out. My current one, which I got directly from Canon in exchange for the old one doesn't exhibit shifting at 6ft...perhaps up to 3-4 ft I can see it.
I mean, it's still shifting, but as mentioned already, it stays within DOF limits, effectively masking it.
Finding a 50L that absolutely does not shift = unicorn.
AGeoJO wrote:
This is more addressed to people that have experienced the focus shift in this lens - Is there a pattern to the focus shift, meaning does it shift focus to the rear of the focus plane or is that inconsistent? If it is consistent, does the shift amount change proportionally to the aperture value used? Meaning did you guys noticed more of a focus shift using f/5.6 than using f/4.0, for example?
Thanks,
Joshua
The amount of shift also varies by copy. My old copy that Canon took shifted even at 6ft out. My current one, which I got directly from Canon in exchange for the old one doesn't exhibit shifting at 6ft...perhaps up to 3-4 ft I can see it.
I mean, it's still shifting, but as mentioned already, it stays within DOF limits, effectively masking it.
Finding a 50L that absolutely does not shift = unicorn.
AGeoJO wrote:
This is more addressed to people that have experienced the focus shift in this lens - Is there a pattern to the focus shift, meaning does it shift focus to the rear of the focus plane or is that inconsistent? If it is consistent, does the shift amount change proportionally to the aperture value used? Meaning did you guys noticed more of a focus shift using f/5.6 than using f/4.0, for example?
Thanks,
Joshua
Mar 18, 2009 at 02:35 PM
p.2 #15Explain the 50mm L problem
A few recent 50L shots as more propaganda:
http://jamiehowell.net/blog/wp-content/uploads/2009/03/perpall-198.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/03/perpall-1457-2.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/couple.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/img_8385.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/img_7942.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/img_8041.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/01/etress-740.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/01/etress-654.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/01/hn8k2777.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/03/perpall-198.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/03/perpall-1457-2.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/couple.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/img_8385.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/img_7942.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/02/img_8041.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/01/etress-740.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/01/etress-654.jpg
http://jamiehowell.net/blog/wp-content/uploads/2009/01/hn8k2777.jpg
Mar 18, 2009 at 02:42 PM
p.2 #16Explain the 50mm L problem
deepbluejh wrote:
A few recent 50L shots as more propaganda:
No doubt Jamie, nice images indeed
Now how many great shots have you missed because of the shift? I'm not asking to be an ass nor am I trying to be condescending at all...I ask in all seriousness. If non, is that because you shoot around the focus shift?
A few recent 50L shots as more propaganda:
No doubt Jamie, nice images indeed
Now how many great shots have you missed because of the shift? I'm not asking to be an ass nor am I trying to be condescending at all...I ask in all seriousness. If non, is that because you shoot around the focus shift?Mar 18, 2009 at 02:46 PM
p.2 #17Explain the 50mm L problem
Real world examples are certainly not welcomed in here!
Mar 18, 2009 at 02:47 PM
p.2 #18Explain the 50mm L problem
The 50L is awesome. Hobbyists seem preoccupied by focus shift, photographers seem to love what this lens can do for them.
Mar 18, 2009 at 02:47 PM
p.2 #19Explain the 50mm L problem
Nice...
Tom Abbott wrote:
The 50L is awesome. Hobbyists seem preoccupied by focus shift, photographers seem to love what this lens can do for them.
Tom Abbott wrote:
The 50L is awesome. Hobbyists seem preoccupied by focus shift, photographers seem to love what this lens can do for them.
Mar 18, 2009 at 02:50 PM
p.2 #20Explain the 50mm L problem
You hobbyist!
M Vers wrote:
No doubt Jamie, nice images indeed Now how many great shots have you missed because of the shift? I'm not asking to be an ass nor am I trying to be condescending at all...I ask in all seriousness. If non, is that because you shoot around the focus shift?
M Vers wrote:
deepbluejh wrote
A few recent 50L shots as more propaganda: Now how many great shots have you missed because of the shift? I'm not asking to be an ass nor am I trying to be condescending at all...I ask in all seriousness. If non, is that because you shoot around the focus shift?Mar 18, 2009 at 02:53 PM