zooming while shooting = epic fail
 

NOTE: I've changed the title of this thread to reflect the actual problem... it'll make sense a few posts down.

After shooting about an hour of footage during a martial arts tournament over 6 hours today, the 5D markII has proved to be unreliable enough that it won't find its way to a live event with me again (which isn't what I bought it for, but still...)

In a significant number of clips (maybe 1 in 5) the 5D2 footage glitches and freezes for about 4 or 5 frames, before resuming. I can cut around much of it, but many shots were ruined (crazy backflips n such, I may post some on Vimeo later).

Has anyone else experienced this? I can't see it being a sensor heat issue, since I was only shooting for 3-5 minutes, then had the camera off for 10 minutes, then back on for 3-5 mins. I don't have a clip longer than 60 seconds, it's not like I was recording an hour long speech straigh.

Also, using the same 133x card I usually do, so I don't think its a card speed issue.

Thoughts? The sensor heat issue is all I got, but it's a stretch.

I have not seen that at all. I am using 133 x cards, Kingston.... When this is occuring, are you seeing the busy signal at right side of frame come on and building up ? I have never had mine go higher than 1 bar... What brand card are you using. How about battery, charged, and the legal one, or are you using another Asian brand like I just got ?

I'm using a 32GB Transcend 133x card ($99cdn at Costco!)... did not see the busy signal at all come to think of it. Most clips were fairly short... and shot a 10 minute long clip yesterday with it with no trouble.

Battery... I have the cheaper Indian knockoff of the cheap Asian brand. :)
I started the day with the stock Canon battery with about 1/4 charge left. When it ran out, I switched to my fully charged Canosonic knock off..... hmmmmm..... the glitches didn't start until later in the day and I don't remember at what point I switched batteries... That will require some more testing. I'll pop the knock off battery back in and do some more tests tonight with a cold camera and see if the glitches come back... then I'll put the stock battery in and see if they stop. Good suggestion! If it turns out its the fault of the knock off batter... hey it's only $8 wasted. :)

I just got one, but have been wondering. I got it with a charger, for $20.00 delivered, but I wonder if the lack of a chip in the knock of creates issues, and I wonder if the the batteries can put out enough juice when needed. Just got mine and I'll do some testing too

Ahaaa!

Putting 2 + 2 together:

I shot the first half of the day using the Canon 24-105L F4
I shot the second half of the day using the Sigma 50-500mm f4-6.3

I zoomed repeatedly during the day on both lenses and almost always used the auto exposure unlocked, with no tricks to lock aperture.

There were no ticks in the first half of the day.
However...
EVERY time I zoomed during the second half of the day, there was a tick. The bigger the zoom, the more the ticks.

So the consistant F4 from the Canon didn't have an issue, but the range from f4-f6.3 from the Bigma made a tick every time I zoomed more than slightly.

Problem solved. Don't zoom with variable aperture lenses while recording.

Good troubleshooting. Very helpful.

I guess i wasn't a coincidence that they paired it with a lens that is capable of constant f4.o.

Chris, just to be sure, I shot a test of both the stock and knock off batteries. It wasn't that. There was no difference between them.

Wouldnt the problem go away if you set the aperture on the Sigma to 6.3 in the low focal length so the lens dont breath while zooming?

If you locked it off with the untwist method, its fine no matter what you do with it. I think the problem is in the computer using processing power to adjust the aperture on its own, not an issue within the lens. I'd dialed up the aperture on a manual lens while recording, and tried the untwist method with the Bigma and not had the problem, which indicates it's in the electronics of the body, not the glass itself.

Confirmed: If the camera has anything to do with the aperture changing, whether it is from zooming or exposure change, you will experience stutters.

Important:
I forced it to stutter WITH EXPOSURE LOCKED while zooming in and out through the f4-f6.3 range.
I made it *not* stutter, using the same lens but with the twist trick, locking the aperture off. No matter what you do then, zooming through the exposure, it will not stutter.

No issues at all when using a manual aperture lens disconnected from the camera electronics.
No stuttering from zooming when using a constant aperture lens like the 24-105 f4... but still have stuttering from aperture change via auto exposure change.

So, if you plan on zooming in/out while shooting anything, you'd better be using a constant aperture lens.
Because...
The camera doesn't care if you've locked the exposure or not, if the aperture changes during zooming, it WILL STUTTER.

As far as battery, I just shot a 13 minute run around our small area here, with a fixed lens, and never had a blink. Battery seems to run fine.

Thanks Dylan, very useful to know.

Well, the problem isn't solved, the camera still has this issue, you just at least are now aware of it and know how to handle it :)

We're still hoping Canon is able to fix this in firmware, but then again, since they mentioned it in the manual, maybe we're out of luck and have to live with it.

Fair enough, how about: "dirty, unsatisfying workaround solved." :)

Should the eyes be the mirror of the mind. I really can not comperhend the Asians. A Christian proverb?

loosing frames during aperture change is a HUGE issue! I hope the firmware in April better give us full manual control..

I'm not quite sure what you are getting at here?

D, I shouldn't have quoted you actually as I'm getting fatally infected from all that Canon bashing. I don't know how they could even sleep with all that karma ;)...

T

This is a non-issue for a non-variable aperture zoom lens if exposure lock is used, yes?

If I use my 24-70 f2.8 or my 70-200 f2.8 or any of my primes or etc., and I lock exposure, then this will never happen.

Doesn't seem like that big of a deal to me actually, sounds more like a lens upgrade is needed...

I don't know if this will help for sure, but if your filming to an SD card, try a full reformat using factory default cards. I have found that over time (about 12 uses) write speeds tend to drop significantly, a full reformat corrects this. Just too cluttered I guess. Anyways, I would try that. Also, I would suggest trying newegg.com for memory purchases, a class 6 16GB SDHC card goes for $30! Thats just my suggestion, I film on HD cards with a video camera, not sure about a digital SLR.

But isn't there still the problem of the shutter speed changing when you zoom - even when locked?

I'm not sure, I haven't used the camera for video with a fully attached Canon zoom for months.

Honestly, I have no idea, but I figured if exposure was locked, then exposure was locked, LOL. But given some of the other ridiculous things Canon has done, I guess even that assumption is subject to questioning, heh. Why would the shutter change if exposure was locked (and you weren't spinning the wheel for exposure compensation)?

I believe it is an aperture change issue.

Yes, the stuttering appears to be related to aperture change. That said, changing shutter speed in the middle of a shot can also ruin a take, just not as epically as dropping frames.

Lens upgrade isn't always an option... nor should it be. In fact, there are only a handful of constant aperture zoom lenses.
Certainly for some people, like filmmakers who can do multiple angles and takes, it isn't a big deal. For event shooters who need to zoom while recording live... it's a big deal as it basically ruins your take (shoot lots of b-roll to cut to... if it is an option).

True. I'd go for a bit of Mylar to decouple the lens. It's cheap and 100% effective.

OK fair enough, but as someone who does events, in my humble opinion at least, an f4-f6.x f-stop does not an event lens make. And there are plenty of constant aperture zoom lenses available, including the holy trinity 16-35mm f2.8, 24-70mm f2.8, and the ultimate event lens, the 70-200mm f2.8 IS. Expensive yes, scarce no.

This isn't a rebuttal of anything anyone has been chiming in with, I'm not saying it doesn't exist or it isn't a problem... Just saying this seems like a non-issue for constant aperture zooms (of which many exist) when exposure lock is used (which should be for every take). That's important info for anyone worried about this.

Good (but expensive) point... and with a 2x TCon you can get the 70-200 up to match the 100-400mm. Hmmm... that is tempting.

And don't forget the f4 series, which are the only zooms I could affort after buying my primes.

BTW: On a variable aperture zoom, if you start with the narrowest opening, nothing will change since it can't go narrower. I used that trick on my 28-135 f3.5-f5.6 until I sold it. Of course using only f5.6 sucks. I set it 5.6 and "locked the aperture" with mylar.

Something had been nagging me for a while about this post, and while I initially agreed with you, I've had to change my mind.

The problem with what you've said here, is that, yes, those are the holy trinity of even lenses........... for photography.... where you only have to snap a few shots here and there and can change lenses without interrupting your work flow.

I have a wide background of live event video, where you need to shoot continuously for half an hour to an hour at a time (if not longer), uninterrupted.... and you need to vary your focal length throughout, from wide to closeups, with the same lens. This means that the still photo "holy trinity" really dont qualify as event video lenses, since they don't have the zoom range to carry you through.

The only "serious" still camera lenses suitable for live video events would be the Canon 28-300L IS and the Sigma 50-500 (barely), neither of which are constant aperture.

Of course, there are tons of type of live events, and multi camera setups would make certain things easier and more complicated at the same time (and ignoring the 12min time limit). In a perfect world you've have 5 camera setups with 5 different lenses, but that's a different topic altogether. :)

My point is back to: The photo holy trinity of film lenses isn't a solution for live video where you can't switch lenses while shooting (ie, most single camera events), and many of us will be back stuck with the aperture "glitch". This of course isn't an issue if you are shooting multi-camera setups where you can cut to a different angle while zooming, or if you shoot enough b-roll to cut away to during zooms.

That's all.... I'm just giving a heads up.... and here I was just about to plunk down $2k on a 70-200L f2.8 IS (nah, I wasn't really, just dreaming. :) )

Dude, if you're looking for a one-man video camera to do events with where that type of coverage is required (consistent run-n-gun for extended periods of time), you've simply GOT THE WRONG CAMERA for the job. And I say that as someone who absolutely loves his 5D2, so don't take that the wrong way. The specific problem discussed in this thread (dropped frames on aperture change) is only ONE reason why that is true, there are many, MANY more reasons as we all know so well (not the least of which is complete lack of manual control, an unsatisfactory audio capability, and a very un-ergonomic form factor that practically requires stabilization at all times).

In my humble opinion, if the focus is film/video (not stills), this camera should only be used as the primary camera under very controlled circumstances (e.g., Indie Filmmaking). For events, weddings, photojournalism, etc., the 5D2 would be better leveraged as a secondary camera or a b-roll camera to supplement the primary (or supplement the AMAZING photography that can be made with the camera).

For me personally, I've been using it to do multimedia pieces of mixed photography and video, and for that, it is quite simply the most amazing camera on the market as far as I'm concerned (despite the long list of shortcomings). But then again, I'm a photographer first, so there you have it.

Totally true... However... there will of course be a lot of people who start shooting live/event video with the 5D2, hopefully this thread will be some help to them.

If the 70-200L F2.8 IS and 24-70L F2.8 are members of the holy trinity, consider me excommunicated. I use all three lenses, and others. I find the 24-105L F4.0 IS sharper although slower and with more barrel distortion, and the 70-200L F4.0 IS is the sharpest zoom in the entire Canon inventory, although again, slower than the F2.8 IS.

I have the older 5D (no video), but whether you are shooting stills or event video, image stabilization only helps with camera shake, doesn't help at all if the subject is moving within the frame.

In my personal experience, with the 70-200 f2.8 IS for indoor, available-light event work, that extra stop at f2.8 plus one or two more from IS (regardless of subject movement) LITERALLY makes or breaks shots. I'm not questioning the sharpness of the f4, just saying that some of us would never even dream of swapping our 70-200 f2.8 IS for the f4 -- you'd have to pry that lens out of my cold dead hands before I gave that thing up. IMHO, the lens is a MUST HAVE for every serious photojournalist, wedding photog, etc.

Bill, you're right. Your work needs speed. I should not dismiss that. And it's the same for the 24-70 F2.8 and the 16-35 F2.8.