Taking the batteries out for 1/2 an hour is not necessary. Anything more than a few seconds is enough to reset the camera. There are no big capacitors in a DSLR to hold a charge.
If the 7D is like the 5D / 5D.2, there is a lithium coin-cell under the port flap. That might also help retain some settings, or it might just be for the date time.
Seems like the AF issues are kind of resolved here. But elsewhere many 7D users have been complaining; I am one of them.
No matter what I do with ALL of the suggestions, the AF is erratic at best, even in good lighting conditions.
Someone even created an online petition so as for Canon to acknowledge the problem and fix it.
I haven't sent my unit yet to Canon for calibration/fixing, for fear that it might just get worse. I thought that maybe I should wait and find a fix someplace else before finally sending it to Canon.
I can only confirm that Live View focusing is much more accurate - contrast detect - than when using phase detect.
angel_d_saint wrote:
Seems like the AF issues are kind of resolved here. But elsewhere many 7D users have been complaining; I am one of them.
No matter what I do with ALL of the suggestions, the AF is erratic at best, even in good lighting conditions.
Someone even created an online petition so as for Canon to acknowledge the problem and fix it.
I haven't sent my unit yet to Canon for calibration/fixing, for fear that it might just get worse. I thought that maybe I should wait and find a fix someplace else before finally sending it to Canon.
I can only confirm that Live View focusing is much more accurate - contrast detect - than when using phase detect.
angel_d_saint:
I had a 7D that wouldn't single-shot AF consistently. I sent it to Canon and got it back still not working properly, THREE TIMES. Instead of sending it back after the fourth time, they sent me a new one. One trip back was all the second one needed.
It is amazing how inconsistent the 7d has been from the factory. Some have worked perfect, some have been flakey and fixed with a software upgrade, some have had multiple trips to Canon and some never get fixed.
Hi, Ernie!
Glad to hear it's all well now with you. =)
Guess I have ro send in mine and expect the worse, so I don't get disappointed. Just hope a little for the best...
Kafn8td, that's the absolute way to describe it.
I was already thinking that I won't expect Canon to replace it with a new one. But I will see if I can have my unit exchanged for a brand new one plus some cash maybe...
I couldn't find my manual for now, so I may as well ask: in C.Fn III: Autofocus/Drive - Lens drive when AF impossible, isn't option '0' (focus search on) mean that the sensor will continue to search for something to focus on while you can also move the camera around the subject to lock focus on, and '1' (focus search off) means that the sensor will stop trying to AF if it couldn't lock to anything initially, even after you move it around? I ask this because the two options behave just the same on my camera.
If autofocus is executed, but focus cannot be achieved, the camera can either keep trying to focus or stop.
0: Focus search on
1: Focus search off
Prevents the camera from becoming grossly out of focus as it attempts to focus again.
Especially convenient with supertelephoto lenses which can become extremely out of focus.
I bought a Manual focus Samyang for my 1D MK III. In AV mode it overexposed by multiple stops. I did a hard reset and all was well. There are some settings from a previously used lens stored in the camera, and occasionally, a hard reset clears up the issues.
p.2 #10 · 7D AF issues...in case you haven't heard
I tried this with 5d2. it did not reset anything after 1 hours (except date and time) all of my mfa was still in place, as well as all the other settings. wondering if there is a 3rd battery inside 5d2. anyone knows?
p.2 #11 · 7D AF issues...in case you haven't heard
kevindar wrote:
I tried this with 5d2. it did not reset anything after 1 hours (except date and time) all of my mfa was still in place, as well as all the other settings. wondering if there is a 3rd battery inside 5d2. anyone knows?
The settings you mention are stored in non-volatile memory, so they will be retained even with no power -- no third battery needed. Instead of needing power to be retained, they need power to be changed.
What would have been reset, in addition to the clock, would be parameters that are not user-settable -- the invisible kind that play tricks on the users.
p.2 #12 · 7D AF issues...in case you haven't heard
BrianO wrote:
...
What would have been reset, in addition to the clock, would be parameters that are not user-settable -- the invisible kind that play tricks on the users.
What would those be? And if they're not user-settable, how would they be different from what they were originally (presumably that's what they'd be reset back to)?
p.2 #13 · 7D AF issues...in case you haven't heard
BrianO wrote:
...What would have been reset...would be parameters that are not user-settable...
Ernie Aubert wrote:
What would those be? And if they're not user-settable, how would they be different from what they were originally?
Oh, lens parameters for example. Lenses have small CPUs in them, and communicate with the camera body they're mounted to.
Jan 23, 2012 at 04:54 AM
haidoz Offline • [X]
p.2 #14 · 7D AF issues...in case you haven't heard
angel_d_saint wrote:
Seems like the AF issues are kind of resolved here. But elsewhere many 7D users have been complaining; I am one of them.
No matter what I do with ALL of the suggestions, the AF is erratic at best, even in good lighting conditions.
Someone even created an online petition so as for Canon to acknowledge the problem and fix it.
I haven't sent my unit yet to Canon for calibration/fixing, for fear that it might just get worse. I thought that maybe I should wait and find a fix someplace else before finally sending it to Canon.
I can only confirm that Live View focusing is much more accurate - contrast detect - than when using phase detect.
I was on the very exact same condition as you are my friend, I've done all suggested solution on the net, they did not solved me anything with the AF issue.
I have one solution, which is worked for me nicely though : Sell the darn thing and replace it with a 5DII. Problem solved. I have a good sleep every nights now
p.2 #15 · 7D AF issues...in case you haven't heard
I just spent a family weekend celebrating three birthdays. Although one of the birthdays was mine, I was, as usual, the designated photographer. I used my 7D and my favorite lens for this situation, the 15-85mm zoom. It normally gives me tack sharp images under the shooting conditions I would experience. All weekend I noticed that the images were appearing slightly soft. All of the shots were taken indoors and I was shooting under my normal manual settings for aperture, shutter speed and flash.
When I returned last night to revieew the images, I was really upset. The images are okay but not the usual tack sharp that I have been getting. I went online for my typical evening FM session and spotted this thread. After reading it, I read several others on other sites which pointed to problems with the AF-ON button, I began to experiment. I have been a "back-button" shooter for years and the addition of the AF-ON button seemed like a natural thing to me.
I began experimenting by first initiating focus with the AF-ON button and then releasing the shutter. Following that shot I used just the shutter button to initiate focus and take the shot. At 100% the differences were clear. The images shot with the AF-ON button initiating focus were just slightly soft, as I had been experiencing all weekend. Those shot using only the shutter button, were tack sharp.
I removed both batteries from the camera, actually three since I had the grip attached, and left the camera overnight. This morning, I re-installed the batteries, reset the date/time info and began shooting. Both methods now give me the tack sharp results I have been getting until this weekend.
p.2 #16 · 7D AF issues...in case you haven't heard
I just sent me 7D in. This is with my 300L F4 IS which was also recently calibrated by Canon. It was tack sharp when I purchased it but it got banged around a bit in my bike's rear carrier. It was in a bag.
p.2 #18 · 7D AF issues...in case you haven't heard
I work on nothing but embedded systems (firmware) these days and what's probably happening is the camera just goes into a powered 'sleep mode' when you switch it from on to off. Microcontroller's internal cache, local SRAM, all these things go into a low power sleep mode, saving their state and consuming very little power. The point is to get instant turn-on, unlike the really old DSLRs where you'd flip the switch on and then have to wait a second or two every time before being able to do anything.
So when it's off it's not really off, the only way to really get it back to zero state is to cut all power and wait a while. Realtime clock (or the whole digital section) has a supercap that keeps it powered for a while even if you remove the battery, but all the custom settings and everything else are probably stored in a high-reliability flash memory.
Or maybe it's temperature related or something like that? Ie. a part that calibrates when power is first applied, and is less accurate if it calibrates hot vs. cold. Who knows, Canon has had a few quirks or possibly hidden features like also the occasional high ISO hot pixel that disappears when you do the minute or so 'sensor clean' mode with no lens on the camera. Phase-detect focus might be trying to adjust or continually calibrate on its own (as it is being used or just sitting there), and when you throw a wierd or third party lens in the mix it gets miscalibrated or thrown out of whack and can't recover.
p.2 #19 · 7D AF issues...in case you haven't heard
Another data point for consideration. I was working with a CPS tech on another camera issue who - unlike the OP's experience - was competent and enthusiastic. He specifically instructed me to pull the battery and the watch battery, let it set for a "few" minutes, reinstall everything, and fire it up. It didn't completely solve the problem we were working on but there was some improvement.
As BrianO has intimated and most of us forget, these cameras are computers. Certain portions of most NVAM are designed to "drain" if unpowered so that they can be reset. I've used similar procedures with desktop computers to solve certain seemingly intractable problems.
The reason that this "hard reset" isn't a universal cure is that the problem sources aren't always related to corrupt NVAM. Make no mistake, NVAM can be corrupted in relatively unpredictable ways. Sometimes the reset works. Sometimes it doesn't. No magic just too many variables to accurately predict what is going to happen. (Anyone who used a Mac in the pre OSX era remembers the "PRAM reset cure" hold down the P,R command and option keys on restart. Make it restart again. Much discussion as to how many times to do it. I liked 3. Let the computer boot. There were specific problems that this procedure would cure.)
The good thing about a "hard reset" is that it doesn't hurt anything and takes very little effort to do. Worth a try, but no money back guarantee.
p.2 #20 · 7D AF issues...in case you haven't heard
NVAM? You sure you don't mean NVRAM?
And don't confuse NVRAM with battery backup RAM. The latter is the one you can clear by removing all power and waiting a while (for any supercaps to discharge if that is part of the design). NVRAM will never clear unless told to, or unless it fails. ie. data corruption caused by high temperature, not unheard especially for the newer MLC flash parts.
Clearing the NVRAM can be a feature of the bootloader or firmware, especially in something like a PC's bios where one or two bad settings can cause it to hang or lock up. But most bios still uses battery backup RAM, as a failsafe because some of these settings can cause it to fail so early in boot that there is no recovery possible. It can even be done automatically if there is a CRC mismatch; in this case a set of reference values are reloaded so that the system doesn't end up bricked for good. The same can happen for firmware, a device may keep a spare or reference version of firmware around in NVRAM to execute from if the original or current version gets corrupted (botched upgrade, corruption, etc.)
