zebras in video recording mode

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thomas bruegger

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zebras in video recording mode

PostFri Jun 28, 2013 7:02 am

While i did my first job with the BMCC MFT yesterday i shot in Video Mode because of straight away workflow with post. While shooting i realized that theres something wrong with Zebras on BMCC it didnt show me clipping while the DP6 was clipping all over on the SDI signal.

I thought i do a little test this morning...

Conclusion: Never rely on Zebras while Recording in Video Rec709 Levels cause the Zebras always show Film Levels, no matter what the camera records at! Bummer, again....

Thomas

btw. now theres the question why the Film-leveled Clip wich slightly clipped in both the BMCC and the SDI is only at 93% IRE on the Parade? thats another stoy (:-).
Attachments
PARADE-FILM-VIDEO.jpg
this is the parade from the recorded DNxHD clips one shot on video- and the other on film levels
PARADE-FILM-VIDEO.jpg (418.51 KiB) Viewed 2967 times
ZEBRA-FILM-VS-VIDEO.jpg
heres the view BMCC DP6 while there is clipping all over in Video Levels the BMCC Zebras dont show it cause they show Film levels.
ZEBRA-FILM-VS-VIDEO.jpg (624.35 KiB) Viewed 2967 times
Thomas Bruegger / garage5 GmbH
www.garage5.ch
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adamroberts

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Re: zebras in video recording mode

PostFri Jun 28, 2013 7:49 am

This has been discussed at length in a few threads already.

The zebras are based on the sensor clipping. In video mode you highlights will clip before the sensor does.
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thomas bruegger

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Re: zebras in video recording mode

PostFri Jun 28, 2013 11:05 am

This has been discussed at length in a few threads already.


yes i have seen it, sad enough that theres not a fixed firmware at that time. this can be such a job killer even if you know.
Thomas Bruegger / garage5 GmbH
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adamroberts

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Re: zebras in video recording mode

PostFri Jun 28, 2013 11:58 am

Set your zebras to a lower level. No need for a firmware fix.
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thomas bruegger

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Re: zebras in video recording mode

PostFri Jun 28, 2013 12:36 pm

Set your zebras to a lower level. No need for a firmware fix.


(;-). i dont get your point AT ALL. if you dont care about having propper meters in camera, have it your way.... dont post here. of course this needs a fast fix, if your 100% zebras arent there when you blow your recorded movies, they either need to be corrected or taken out, but as it is now it is missleading, end of story.
Thomas Bruegger / garage5 GmbH
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sean mclennan

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Re: zebras in video recording mode

PostFri Jun 28, 2013 2:33 pm

thomas bruegger wrote:
Set your zebras to a lower level. No need for a firmware fix.


(;-). i dont get your point AT ALL. if you dont care about having propper meters in camera, have it your way.... dont post here. of course this needs a fast fix, if your 100% zebras arent there when you blow your recorded movies, they either need to be corrected or taken out, but as it is now it is missleading, end of story.


How is it misleading? Zebras are a visual tool for showing clipping. On the BMCC it's done at the sensor level. Since it's adjustable, you find the setting you need for YOUR workflow and you're done. Seems pretty straight forward to me.

Don't tell other forums members to "don't post here", especially one that has been here form the beginning and contributed a lot of useful information to the group like Adam. Just because other people don't share your "opinion" doesn't mean their input is any less valid than yours.
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adamroberts

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Re: zebras in video recording mode

PostFri Jun 28, 2013 3:59 pm

thomas bruegger wrote:
Set your zebras to a lower level. No need for a firmware fix.


(;-). i dont get your point AT ALL. if you dont care about having propper meters in camera, have it your way.... dont post here. of course this needs a fast fix, if your 100% zebras arent there when you blow your recorded movies, they either need to be corrected or taken out, but as it is now it is missleading, end of story.


Have you used zebras on other cameras? On cameras like Sony ENG type cameras you would set your zebra at 75%. Very seldom would they be set yo 100%. They are tools to help you get your preferred exposure. The only way you find your perfect setting is to test it. That is why you have the option to adjust the zebras.

So the camera works as intended. Thats my point.

Do some tests and lean to use the zebras for your preferred style of exposure in video mode. The only time you would have zebras set to 100% is when shooting RAW. Even in Film mode when shooting in high contrast scenes, like outdoors in mid day, 100% zebras is often to much.
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Peter J. DeCrescenzo

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Re: zebras in video recording mode

PostFri Jun 28, 2013 4:18 pm

A point that took me a while to understand is that BMCC zebras do not display standard IRE values, but instead are related to the camera's sensor clipping.

It's not a bug, it's a feature: It's how the camera works.

Yes, it's different than other video cameras. But it works really well.

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thomas bruegger

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Re: zebras in video recording mode

PostFri Jun 28, 2013 4:38 pm

no offence guys, but i think i have a point here and felt like its not really understood, maybe im wrong, if so im sorry.

the way i used zebras in the past is 100% for highlight-clipping and 70% to get good skin level. i have never used a camera where a 75% zebra would clip highlights, like the BMCC does in Video Mode.

The Zebra in Film Recording mode on BMCC is like i think it should work. Wouldnt you agree that when in Video-Mode the Zebra should work the same way? 100% is the point where the highlights clip?
Thomas Bruegger / garage5 GmbH
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Aaron Scheiner

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Re: zebras in video recording mode

PostFri Jun 28, 2013 5:20 pm

I agree with you Thomas.

When using a standard video camera I usually set the zebra level to 100+, so I have an idea of what is clipped and what is not. I feel the BMCC should at least provide the option for setting zebra level at a video level when shooting in video mode. Zebra based on sensor-level clipping is totally useless in video mode. All this is another example of the beta nature of the BMCC's firmware. I'm hoping there will be a mass update when the 4k camera comes out.

Fortunately I barely ever shoot in video mode (I've pretty much used my cameras in raw mode only).

It's like we've got a BMD fan club here... and any brother who speaks out of turn is exiled.

Who the hell would want VU meters anyway ? ;) .
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adamroberts

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Re: zebras in video recording mode

PostFri Jun 28, 2013 7:28 pm

I would love VU meters. I'd also love some sort of disc space remaining indication... There are many things that could be added. Many things that are available on other cameras. Most of those cameras cost more than twice the price of a BMCC.

I think the zebras "issue" is less of an issue. It's certainly not a bug in my eyes. The camera is marketed as a cinema camera and as such the zebras work for that purpose. I don't think that makes the firmware "beta".

If you want to shoot ENG style there are many cameras better suited for that style of shooting. If you want to use the BMCC in video mode like an ENG camera it only takes a bit of testing to find the right exposure setting for your preferred style.

Like any camera, you should test it before using it on a job. How else will you know if you are working within its capabilities?

Why should this camera work like an ENG camera when its clearly not designed to be one?

I'm not a fan boy. I own a few cameras and use the right one for the job I have to do.

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