p.2 #2 · Canon EF 40mm f/2.8 Firmware Update Available Now
Hawkan wrote:
This problem is actually very sloppy. Canon's QA people should have gotten this almost immediately (early in the testing cycle). A simple state diagram and a quick test would have revealed it.
Monito wrote:
Nonsense.
Hawkan wrote:
Thank you for you insight. Care to elaborate?
This kind of problem has not been seen before; at least I've not heard of it reported for any camera or lens on the web. Thus in the first place it would not be the kind of thing that could be predicted; i.e. it is not a "known unknown", it was an "unknown unknown". Therefore I think this kind of problem is not on any of the manufacturers' radars.
However, since you are the one asserting that it is so simple and a quick test, perhaps you should present the state diagram and the quick test that would uncover this intermittent fault affecting only a few of the lenses and not encountered in the pre-production series.
p.2 #3 · Canon EF 40mm f/2.8 Firmware Update Available Now
DarthMTS47 wrote:
I'm pretty sure this is a function of the new stepper motor drive. Depending on the kind of stepper motor used, there is no feedback loop. The drive tells it to go a certain number of "steps," and the motor moves to that position and holds. If you push in the lens element, it may move the position of the steps, so the drive gets "confused" and doesn't know where it is. Remounting the lens probably forces it to redetermine its location so it can move properly. The firmware update probably just has it double-check its location every time you start to auto-focus.
I pushed the lens in by hand, while mounted on my powered up 5D Mark II, but it keeps on working fine. I tried pretty much everything, but no issues with that camera anyway.
p.2 #4 · Canon EF 40mm f/2.8 Firmware Update Available Now
If it happens in the bag, perhaps it happens when both the shutter button is half-pressed for AF and the lens is squarshed. In other words, compression on the lens while the AF runs.
Does the external lens body move? In particular does focusing cause a protruding part of the lens to move, maybe even rotate?
p.2 #5 · Canon EF 40mm f/2.8 Firmware Update Available Now
Thank you for your reply, Monito. I would love to see how Canon (or Nikon) handles QA in general and with regards to current cameras and lenses in particular.
I realize I am taking this quite far off topic, but I'll keep it short...
I do not agree with you that it would be an "unknown unknown": It is obvious that you can move the barrel of the lens. How does the software (lens firmware) respond to being started with a different mechanical state than expected (which would happen if the mechanical state is altered when the software is sleeping)? What different mechanical states are there and what are the different software states?
Also, adding the factor that it has to work on different camera bodies of course makes this a lot more complicated, but the problem is still related to the lens firmware. They already have a set of rules laid down for communication with camera bodies, so as long as the lens complies with those there should not be a problem with different camera models.
This is not rocket science, even if the folks over at Canon are sort of breaking new ground here. I realize that it takes more than a simple state diagram to test for all possible situations, but it is a good start when combining electro-mechanics with software.
If you want to take this further, feel free to contact me in private, as I highly doubt anyone else here cares.
I - for the record - still think the problem appears as quite sloppy on Canon's part. Good thing you can upgrade firmware these day.
p.2 #6 · Canon EF 40mm f/2.8 Firmware Update Available Now
Monito wrote:
If it happens in the bag, perhaps it happens when both the shutter button is half-pressed for AF and the lens is squarshed. In other words, compression on the lens while the AF runs.
Does the external lens body move? In particular does focusing cause a protruding part of the lens to move, maybe even rotate?
Yes, it does; no rotate, just the glass moves to focus, and when you push into the front, it sweetly go back to infinity.
p.2 #7 · Canon EF 40mm f/2.8 Firmware Update Available Now
Thanks Hawkan for sharing your thoughts.
Hawkan wrote:
I do not agree with you that it would be an "unknown unknown": It is obvious that you can move the barrel of the lens. How does the software (lens firmware) respond to being started with a different mechanical state than expected (which would happen if the mechanical state is altered when the software is sleeping)? What different mechanical states are there and what are the different software states?
I am sure that Canon tested for exactly that basic scenario. However, there are many other scenarios and possible sequences of events. The exact one that leads to the problem may be more complex than simply moving the barrel of the lens externally. Remember that most people are not experiencing the problem, so it is intermittent or it requires a set of circumstances to come together.
Do you know which exact sequence of events puts the lens into the malfunctioning state? If so, it would be useful if you stated them.
Hawkan wrote:
A simple state diagram and a quick test would have revealed it.
Monito wrote:
Nonsense.
Hawkan wrote:
I realize that it takes more than a simple state diagram to test for all possible situations
So.
Life is not simple; nor are high tech manufacturing processes for precision instruments that are complex enough to require firmware. Without knowing the exact parameters of the use case that triggers the problem it is jumping the gun to say that the manufacturer was sloppy about testing.
ultrapix wrote:
Yes, it does [move]; no rotate, just the glass moves to focus, and when you push into the front, it sweetly go back to infinity.
Thanks ultrapix for the background. It's an interesting problem.
p.2 #8 · Canon EF 40mm f/2.8 Firmware Update Available Now
dwweiche wrote:
Odd. A firmware update that addresses an issue caused by mechanical pressure on the lens?
Sounds like a software work-around to a hardware issue
How does this firmware update work? you're actually updating the lens' firmware ( if there's one ) thru the camera? or we are updating the camera's firmware?
Aug 07, 2012 at 03:56 PM
brad_s Offline • • • [X]
p.2 #9 · Canon EF 40mm f/2.8 Firmware Update Available Now
Thanks OP, this is what I was looking for. I got the 40mm and thr 5D3 at the same time and couldn't figure out which was the culprit. The problem happened to me about 5 times already.
p.2 #10 · Canon EF 40mm f/2.8 Firmware Update Available Now
Anybody that's been having problems or experiencing femonemons with this lens, I would advice taking it to the nearest IHOP. (How do you spell femonemons anyways)
p.2 #11 · Canon EF 40mm f/2.8 Firmware Update Available Now
I tried intentionally pushing on the lens barrel and still could not get it to lock up. Maybe mine is outside the faulty batch. Never has locked up on me or anything.
p.2 #12 · Canon EF 40mm f/2.8 Firmware Update Available Now
jaybird555 wrote:
Anybody that's been having problems or experiencing femonemons with this lens, I would advice taking it to the nearest IHOP.
I've used my 40 quite a bit so far and have had it dangling off my side where it's had to have been impacted & bumped from normal movement and has never once given me this issue.
Omar
jaybird555 wrote:
...(How do you spell femonemons anyways)
p.2 #17 · Canon EF 40mm f/2.8 Firmware Update Available Now
Monito wrote:
This kind of problem has not been seen before; at least I've not heard of it reported for any camera or lens on the web. Thus in the first place it would not be the kind of thing that could be predicted; i.e. it is not a "known unknown", it was an "unknown unknown". Therefore I think this kind of problem is not on any of the manufacturers' radars.
However, since you are the one asserting that it is so simple and a quick test, perhaps you should present the state diagram and the quick test that would uncover this intermittent fault affecting only a few of the lenses and not encountered in the pre-production series. ...Show more →
Seriously Monito, do you think it's your job to defend Canon? Are you always seem compelled to attack anyone that dares to criticize the company you seem to worship?
Canon is fallible, and they consistently release products with faults, errors, etc. Again, that would be consistently and it's not the job of anyone here to design test programs for them.
My new 40mm lens began demonstrating the problem starting weeks ago. It's a PITA when you're scratching your head and wondering "WTF is going on now?" and if it happens to thousands (100's of?) this should have been caught before release. Period.
p.2 #18 · Canon EF 40mm f/2.8 Firmware Update Available Now
When people write nonsense, jamesf99, their statements deserve to be corrected. Hawkan later admitted in the thread that it would not be a simple state diagram and quick test.
Go ahead and write some nonsense about Nikon in this thread and I'll call it out too. Use Leica if you prefer. I'm not defending Canon; I'm defending clear thinking.
The fact of the matter is that it would not be a simple state diagram and quick test and thus Nikon or Pentax or Canon or Sony would not have gotten it early.
Of course Canon is fallible. That's obvious and indisputable. After all, we are discussing a lens problem. Of course an intermittent flaw occuring in only some examples is a bother.
Finally, I attacked the idea ("simple state diagram") by calling it "nonsense", but you attack the person by mistakenly accusing me of attacking the person. Please read carefully. The word "nonsense" is a noun that applies to statements and concepts. The word "nonsense" is not applicable to people. In English we don't say "You are nonsense", but we do say "The statement is nonsense". So it is clear to most people that when the word "Nonsense" is used alone it is not referring to the person but rather to the statement. Thus it is not an attack on a person. I try to write clearly and directly but I'm willing to expend more words if it will help people understand. How verbose do I need to be for it to be clear enough?
It is important to discuss the ideas and statements rather than the person because persons (like me and like Canon and Nikon) can be fallible. Thus a person can make a nonsensical statement and someone can disagree with the statement without most people thinking it is a personal attack. Unless some people are known to be infallible, but I don't know of any such people. When someone writes "nonsense" in response to a post, they did not write "you are nonsensical" or "you have no sense" which would be an attack on the person; but that did not occur because that was not what was written. Please read what is written, not what you would like to see written. I choose my words carefully and the least that can be done is to read them carefully.
I hope that has clarified the distinction between statements and people.
p.2 #19 · Canon EF 40mm f/2.8 Firmware Update Available Now
bottom line,
1. the problem can be addressed by a firmware update,
2. the lens is a fantastic performer. Fact is that after I acquired this lens, I sold both 35L and 50L.
