Canon EF 40mm F2.8 STM
- Thread starter spinworkxroy
- Start date
Lovely...
Here's a few images from my pancake
More images here:
500px / Tiong Jin / Meet my little artists
Not going into very technical review. When i compare side by side with my 50mm "L", I would say it's a why not!
& this might be your most expensive camera body cap, leave it on.
This lens' centre sharpness is good. Below is a 100% crop of this lens shot wide open on my 5D3.
ISO12,800, f/2.8, 1/500s:
See the amount of details..
is this your sexy lips?
avsquare
Senior Member
is this your sexy lips?
nope... haha.
esoeij
Senior Member
I just read about this review on a FredMiranda forum: "Nice picture quality and a joy to use except for that the autofocus stops working occasionally - kind falls asleep. Turning the camera (7D) off/on doesn't help and the lens has to be removed from the camera body to wake up again, then it works excellent till the next time it falls asleep....and no it's not on manual focus."
Does anyone face a similar issue? My copy did this to me twice too (using it on a 5D3 with latest firmware updated already). The AF just stopped working for no apparent reason, but was perfectly fine again after I detached and reattached the lens.
Does anyone face a similar issue? My copy did this to me twice too (using it on a 5D3 with latest firmware updated already). The AF just stopped working for no apparent reason, but was perfectly fine again after I detached and reattached the lens.
I experienced this on my 60D. I removed the battery and inserted in after 10 seconds and it worked.
i've been using mine on 3 different cameras - 350D, 5D and 1dsMk2. no problems so far. could it be your lens' STM is wonky? :think:
esoeij
Senior Member
That's what I suspect. But I thought it was just me, until I read about this phenomenon happening to someone else. Looks like CSer Evilcat had a similar experience too. I'm just wondering if there are others and if this is potentially a manufacturing defect or some sort of software issue. Oh well, lucky I bought a local set with warranty.
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avsquare
Senior Member
Nope, this is the STM issue. I had the same problem.
Esoeji bro, this problem happens when you force the "zoom" in when your camera powers off. As we know, the lens extends a little when focusing. Some people have the tendency to force this extension back by pushing it by force when they want to store their camera or lens.
It is not recommended to do so. For USM lens, I recommend retracting the extension by using focus ring. HOWEVER, the problem with this STM lens is that the manual focus DOES NOT work without power on. It's the same idea as the USM motor for 85L.
Thus, to prevent this issue, I suggest the following methods to retract the extension when you want to keep it:
1) Manually turn the focus ring while your body is powered on to retract the extension
2) Place your lens cap on and half press the shutter button. Since lens cap is on, lens will focus hunt by zooming from MFD to infinity. As such, the lens will extend to the max, then retracts to the minimum. When it is at the minimum, release your hold on shutter, and turn off your camera body.
The above will fix your problem. I doubt CSC can do sh1t about it, it's a design issue.
In anycase, if you do happen to force on (accidentally or not) the focus extension while power is off, when you turn on your cam, the AF will fail. To fix this, turn off your cam, disconnect your lens and connect it back.
Hope the above helps.
avsquare
Senior Member
Hmm call their call centre and ask which email add to send lo.. Actually I found out this issue since start but didn't bother to tell Canon since it's a "cheap" lens and didn't expect too much from it
raptor84
Senior Member
raydio
Senior Member
Canon should know about this issue even you intend not to do anything about it. Worst case scenario is that they continue to use the same design in future lenses... then problem just multiplies.
spinworkxroy
New Member
And all along i thought i was the only one…i actually always manually force the extension back because it sticks out when i turn off the camera 
And i too experienced it hanging…i thought it was just me..looks like it's an STM problem that you CANNOT force it back
But it' a small issue i guess. just have to remember to close focus before turing off i guess..
And i too experienced it hanging…i thought it was just me..looks like it's an STM problem that you CANNOT force it back
But it' a small issue i guess. just have to remember to close focus before turing off i guess..
esoeij
Senior Member
Looks like this issue is really common (read the comments dated 1 July onwards). The only minor consolation is it turns out I'm not the only one with this problem. Lucky this lens is relatively cheap. In USA they have the option of just returning it and get a refund. In SG, I think the shop will tell you go settle it with Canon. Haizzz.
LensRentals.com - Canon 40mm Pancake – How Did They Do That??
LensRentals.com - Canon 40mm Pancake – How Did They Do That??
photoart
Senior Member
Oh it happened to me on the first day of use. The auto focusing suddenly stopped working.
I could not autofocus nor manual focus, and my first thought was that I've gotten a lemon. But I didn't panick since its under warranty.
However after taking out the lens and putting it back on, it worked again. No problems so far
I could not autofocus nor manual focus, and my first thought was that I've gotten a lemon. But I didn't panick since its under warranty.
However after taking out the lens and putting it back on, it worked again. No problems so far
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