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5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL

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Heath Cozens
5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 11, 2010 at 7:10:50 pm

Hi all,

Please have a look at the footage here: . Would love to hear your comments on this bizarre flicker/ interference issue.

The Vimeo link explains more fully, but for your reference, here's what I wrote:

This is a quick and dirty camera test that I ran after encountering major flicker issues shooting PAL, in Osaka, where the electricity cycles at 60hz (like North America).

The results are, as you can see, disturbing. Could it be that the 5d is totally unsuited for shooting PAL in 60hz territories?

The problem came to light when I was shooting documentary test footage with a local subject who I had previously only shot on PAL DV. Shooting PAL DV at a shutter speed of 60, of course, there had been no
issues.

But switching to the 5d and continuing to shoot PAL under the same 60hz fluorescent light, flicker, if that's what it is, was in every shot, regardless of shutter speed.

I packed in the filming for the evening, went sat down and pointed the camera at the pavement to conduct a quick test of what shutter speeds worked, and at what frame rates.

When I got back to Tokyo (50hz, like Europe) I pointed the camera at some more flouro-lit concrete (worst art film ever...) and cycled through the various frame rates and shutter speeds again.

I find it hard to believe, but it appears that depending on the region, you simply cannot avoid flicker when shooting PAL under fluorescent or mercury vapor lights.

The funny thing is that NTSC looks fine regardless of shutter speed.

It looks like some kind of interference pattern - a diabolical collusion between the scanning speed of the sensor and the flicker of the lights?

Would love to hear your experiences - especially those who've been shooting PAL in, say, the States...

Vital statistics:

Currents: 50hz (first half/ shot of stairwell), 60hz (second half/
shot of pavement)
Frame rates: standard 5dmk2 rates of 23.976, 25, 29.97
Shutter speeds: 30, 40, 50, 60, 80, 100


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Phil Balsdon
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 11, 2010 at 10:05:30 pm

This is the result of shooting under fluorescent lighting with out of sync shutter speeds.

See how the flicker changes as you change shutter speeds. When in PAL environment shoot at 1/50 shutter speed and in NTSC 1/60. Shooting outside these speeds will cause flicker under fluoros.

What's with the PAL at 29.97? This is wrong, PAL is 25p.

There's nothing wrong with the camera, all film video and video cameras will behave like this.

Cinematographer, Steadicam Operator, Final Cut Pro Post Production.
http://www.steadi-onfilms.com.au/


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Heath Cozens
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 12, 2010 at 2:16:34 am

Hi Phil,

Thanks for checking this out.

Actually, the point I'm making here is that the DSLR is not behaving as a normal video camera would.

Normally in a 60hz environment, you have to shoot at a shutter speed of 60 to eliminate flicker. With the 5d, it appears that this doesn't work.

In fact, when shooting PAL, any shutter speed under 60hz lights results in flicker. Conversely, shooting NTSC under 60hz at any of the lower shutter speeds produces acceptable footage.

For clarity, I'd like to recap methodology.

The first half of the video covers 50hz electricity.

Under 50hz, I shot at 23.976fps (cinema frame rate) at shutter speeds of 30, 40, 50, 60, 80, and 100. In the same 50hz location, I then shot at 25fps (PAL) using the same shutter speeds. Finally I shot at 29.97 (NTSC) using the same shutter speeds again.

For the second half of the video, the above procedure is repeated but in a location where the current runs 60hz.

If you have time, please have another look. I think you'll notice some very peculiar behavior.

Heath

NB: the locations are in Japan, which is cursed with two electrical systems - both 50 and 60hz, despite being exclusively NTSC. I shoot both PAL and NTSC here depending on the job, but I've never encountered this kind of issue before.



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Frank Amann
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Mar 27, 2013 at 12:23:56 pm

Hi Heath Cozens,

did you yet find a solution to the flicker problem with the 5D shooting PAL in 60Hz environments though setting the shutter to 1/60?

I'm asking because I encountered the same problem this January shooting in New York. Much of the ambient lighting (not only fluorescents, but energy saving bulbs, some street lights) showed flicker which I couldn't stop by any exposure time (the best behaviour I found with 1/40 (strangely enough), second best was 1/60). There were no issues whatsoever with my own litepanels sources (which was to be expected).

There also were no issues shooting with the C300 at 1/60.

Cheers,
Frank (based in Berlin, Germany, which is PAL and 1/50)


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Thomas W. Silkwood
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Apr 19, 2012 at 10:44:20 am

A POINT OF INTEREST: We have encountered a different problem. I'm a American and work in Thailand. We work in multi-system environments so my team works with lots of teams from all over the world. On one occasion it wasn't possible for a USA team to rent all the florescent lights they needed so they decided to us standard florescent tube lights, the kind you put in your work shot back home. The florescence looked okay except for one bank. The USA team came to us and asked for help. They couldn't figure out why one bank of lights had the flicker. I noted that they gelled all their lights except the one they were getting flicker from. I suggested they gel this light too and the flicker was gone. I thought some of you might find this interesting.


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Michael Sacci
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 12, 2010 at 6:45:35 am

I'm pretty sure Phil answered the question.


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Heath Cozens
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 12, 2010 at 1:33:02 pm

There are still a lot of question marks remaining for me.

Phil wrote "When in PAL environment shoot at 1/50 shutter speed and in NTSC 1/60".

Japan is an NTSC environment, but has both 50 and 60hz electricity running in different parts of the country but I think the point that Phil's making is that when the mains run at 50hz, shoot at 1/50th, when it's 60hz, shoot at 1/60th... (correct me if you meant something else Phil)? That makes sense and yep, that's what I normally do.

In 60hz, the flicker isn't resolvable through shutter speed adjustments when shooting in PAL. But in 24 or NTSC, shutter speed doesn't matter much at all- odd.

I guess it's conceivable that some mercury vapor lamp effect might have crept into the footage but I don't think so..

Maybe Canon can help. I'm taking it in tomorrow.

Cheers


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Noah Kadner
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 12, 2010 at 8:06:07 pm

I've had this exact thing happen with NTSC camcorders of all flavors in 50hz countries. It's not really an Achille's heel of this one camera so much as all of them... Anytime you mismatch your broadcast standard with your lights you can potentially run into this exact issue. Short answer is, don't....

Noah

Unlock the secrets of 24p, HD and Final Cut Studio with Call Box Training. Featuring the Canon 5D Mark II and 7D.


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Phil Balsdon
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 12, 2010 at 9:20:07 pm

I guess it's conceivable that some mercury vapor lamp effect might have crept into the footage but I don't think so..

Maybe Canon can help. I'm taking it in tomorrow.


Maybe you also need to contact the Japanese energy supplier and ask if it's 1/60 and not 1/59.8 or something almost close to, because your shots almost sync at that one odd speed combination you're finding fault with.

Hardly an "achillies heel".

Remember these cameras were originally offered as something press photographers could use occasionally for video. You know, the guys that work for the newspapers that now need video for their online services.
Us lot, (film and video shooters) discovered the wonderful properties of full sized CMOS chips. They're not primarily designed as video cameras and so very very occasionally they may not be the quite perfect tool for the job. They do not have a "clearscan" function that allows syncing at infinitely different speeds.

Cinematographer, Steadicam Operator, Final Cut Pro Post Production.
http://www.steadi-onfilms.com.au/


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Peter DeCrescenzo
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 13, 2010 at 7:06:41 pm

[Phil Balsdon] "... They do not have a "clearscan" function that allows syncing at infinitely different speeds. ..."

Hi Phil: Just an FYI: I was pleased to see Panasonic's new AF100 m4/3 camcorder has a "Synchro Scan" item in its menus, as seen in at the 5:20 point in this video:
http://www.videoaktiv.de/Praxis+Technik/CAMCORDER-Hintergrundinfo/Video-Vor...

Since the AF100 in the demo is an unfinished engineering prototype, it remains to be seen which features make it to the final shipping version of the cam.

See also:
http://forums.creativecow.net/readpost/280/2893

Cheers.

===


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Phil Balsdon
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 13, 2010 at 10:38:00 pm

[Peter DeCrescenzo] Just an FYI: I was pleased to see Panasonic's new AF100 m4/3 camcorder has a "Synchro Scan"

Hi Peter, I've always been a big fan of Panasonic, always preferred the Varicam as an HD camcorder.

The thing with the AF100 is it's only a 4/3 sensor. When will manufacturers find out exactly what cinematographers want or just research what is driving the market and why? The Canon 5D is the most popular HD DSLR camera. Why? Because it's got the largest sensor which offers the lowest depth of field. The 7D is more economical and has other features such as 50p / 60p recording. The 1D Mk4 is more expensive with formidable low light capabilities but the 5D is the better seller. For this feature alone cinematographers and directors are prepared to put up with all the other problems of shooting moving images with these cameras, and there are many, but for which there are work-arounds. There is no work-around that will replace the benefits of the full size sensor.

Sadly the moment another manufacturer offers an equivalent camera with a full 35mm size sensor the Panasonic AF100 will be an also ran.

Cinematographer, Steadicam Operator, Final Cut Pro Post Production.
http://www.steadi-onfilms.com.au/


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Peter DeCrescenzo
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 14, 2010 at 12:00:24 am

[Phil Balsdon] ... "Sadly the moment another manufacturer offers an equivalent camera with a full 35mm size sensor the Panasonic AF100 will be an also ran." ...

Hi Phil: I hear you, and your point is well taken, but I hope you will agree that there'll never be a perfect camera which fits all budgets and project requirements.

Every camera is an also-ran at some point, even the beloved 5DM2.

A "full-frame" DSLR cam can be perfect for some projects, and it can be inappropriate for others (difficult to focus, alias/moire artifacts, etc.).

As you probably know, the image area of the m4/3 sensor in the AF100 & GH1 is more than 4 times the area of the sensor in a typical pro 2/3" camera. Thus, m4/3 has nice DOF characteristics. Can't get as narrow DOF as the 5DM2's sensor, but not too shabby.

As I understand it, compared to 35mm _motion_ picture film, the AF100 & GH1 sensor (when used in 16:9 mode) has a 1.18 crop factor.

Anyway, it's great we have so many good tools to choose from!

Sorry to take this thread off topic. Cheers.

---

http://www.peterdv.com


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Richard van den Boogaard
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Sep 12, 2010 at 8:30:06 pm

I would like to take this discussion into a somewhat different direction - with the 7D you have the option of choosing 60fps when the camera is set to NTSC with the accompanying shutter speeds of 1/100 and 1/125. That could result in a nicer slowdown when edited at 25fps than 50fps.

At one project this summer that was shot entirely in slomo, we were considering use of 60fps, but chose to switch to 50fps in the end. I'm guessing now, that was a wise decision...

Richard van den Boogaard
cameraman / editor / video marketing consultant

Branded Channels
W: http://www.brandedchannels.com


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Wayne Matheson
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Jul 29, 2011 at 4:31:24 pm

Hi, I found a simple solution to this problem when filming in China was to use incandescent lighting and DC light sources. This seem to eliminate the problem. Due to the unstable AC power supply in China, we only experienced the flicker from time to time when using fluorescent lighting sources. The frequency of the AC power seemed to shift at times and the flicker would appear. When we added incandescent light sources, the flicker went away. For one outdoor night scene, we used gas lanterns. Using a generator would be another solution to this problem, as you can select the output voltage and frequency on some models.

Wayne


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Chris Peckham
Re: 5d's Achilles' heel? Bizarre, horrible flicker while shooting PAL
on Aug 10, 2011 at 3:24:31 am

I have also run into the same problem shooting PAL in Australia under flouro lights (daylight Osram bulbs) both on a 5d and 7d. I don't want to be limited to tungsten lights. I'll try a few suggestions on some other sites but haven't found a workaround as yet.

Iechyd da ("Yachy Da" Welsh for Good Health)


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