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Zebra Levels (white very BRIGHT)

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Antonio Atzei
Zebra Levels (white very BRIGHT)
on Sep 18, 2008 at 10:18:23 am

Dear Cows
Looking at footage I've done last weekend (a photographer and a model) I've noticed something strange.
While the exposure its correct for the clips with the model and her dresses, when the photographer is on view (is wearing a white t-shirt)I've noticed that there's no details on the white t-shirt, actually it seams way to bright. I've done white balance before every shoot/scene
Some details below

Camera: SONY Z1
WB OUTDOOR LVL-- 0
GAIN SET UP-- H6 M3 L0
ZEBRA LVL--90

There are any special settings or rules to follow if you are going to shoot for example a white gown like a wedding dress, without loosing the intricate details and off course without compromising the whole picture?

N.B.
The white t-shirt looked ok on both display and preview monitors

ciao
AA


BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
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FCS 2
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Rick Wise
Re: Zebra Levels (white very BRIGHT)
on Sep 18, 2008 at 5:27:59 pm

Your problem has nothing to do with white balance, and everything to do with exposure. If you set your zebras to 100, anything at 100 or above will "clip" -- there will be no detail. Your white shirt must have been at or above 100 IRE (which is what the zebras are indicating.) You apparently set your zebras to 90, which was of little use to you.

White shirts, dresses, etc. are always a problem, especially for small HDV cameras, especially in hard light. If you expose for the white, then faces tend to be underexposed a bit. As you probably know, in post you can boost the middle level of exposure and leave the shadows and highlights relatively alone. So your best bet is to expose for the whites, then in post bring up the faces a bit.

Going the other way -- exposing for the faces and letting the whites blow out -- is impossible to correct in post, for the reasons stated in the first paragraph.

Zebra levels: if you set your zebras to 70, which I recommend for most shooting, and adjust exposure/iris so that there is just a tiny bit of zebra on the hottest part of the face, and the face you are adjusting for is Caucasian, you will get a "correct" face exposure for everyone in the scene, no matter how dark or light. Some good cameras, such as the DVX100/a/b will not let you do that -- the lowest zebra is 80, which is a bummer. If your subjects have dark skin, you can "borrow" a white hand or face to set exposure, or else learn how much to stop down the iris on a particular shade of dark skin after you find a twinge of zebra.

On the other hand, if you are shooting outdoors with lots of sky, you might want to set the zebras to 100 so that you adjust exposure to get some detail in the hot sky. This adjustment is often a hard dance to pull off, as you are likely to make the ground-level stuff a bit dark. One solution is to frame so that there is not much sky, and to let the sky "blow". This is the curse of video -- can't handle the range from hot sky to dark shadow. Film has much more latitude, though the newest big HD cameras, such as the Sony F23, are approaching that beautiful ability.

Rick Wise
director of photography
Oakland, CA
http://www.RickWiseDP.com
email: Rick@RickWiseDP.com


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Antonio Atzei
Re: Zebra Levels (white very BRIGHT)
on Sep 19, 2008 at 5:57:29 am

Rick

It made perfect sense thank you for your suggestions!

I need to keep in mind that HDV can be a bit tricky sometimes. I've just showed the clips to the photographer and he was very impressed, Oh well to loose 5 or 10 secs of tape because of a overexposed t-shirt its not the end of the world

thanking you again

ciao
Antonio Atzei

BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
4.5GB RAM
1 TB OF MEMORY.
FCS 2
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Eric Lagerlof
Re: Zebra Levels (white very BRIGHT)
on Sep 21, 2008 at 4:29:11 pm

Antonio, I just saw the earlier posting about walking around backstage during a fashion show. If all you had was one blown out T-shirt, it sounds like you did pretty darn good, given the run & gun nature of the shoot.

I'm curious, did you go full manual or leave the Z-1 on auto exposure? If the latter, there is a menu item that allows you to a bit of control on auto exposure's 'ceiling', how many ire above or below 100 ire it will stay open at. Being on auto iris can help in run & gun situations. Especialy if you know your camera's buttons, clicking off auto iris and going to manual is not all that hard, even handheld.

I shoot live theater and an extra step or two downstage can raise an actor's levels 10-20 ire, while everyone else's exposure stays the same. Generally I try and find the hottest location/white costume combo on stage, adjust it to 90-95 ire, make note of the f stop and work the show from there.





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Antonio Atzei
Re: Zebra Levels (white very BRIGHT)
on Sep 22, 2008 at 1:38:29 pm

Eric
Because of the nature of the project I new that I was going to run into trouble sooner or later and thats why I posted few questions in a couple of forums. I was aware of the issues because I do work full time for the fashion house that organised the event. Put it this way the premises were not to my knowledge the best location for this kind of event. To give you an idea it was all black from stage to the catwalk. I was there well ahead of time to set up the camera and to some WB from different locations and after talking to the guys running the consol and lighting I was at first confident that I was ok.... big mistake bacause when the show started the lighting was completely different and midway through the show I had to gurd the camera against the guests. To many people where allowed in for such small place anyway nonetheless I LOVED IT no matter what it was fantastic I shot almost 60 min of tape and to unswer your question in manual. I managed to salvage only part of it but thats good enough because on the dvd I'll use some of the photos done by the official photographer, so I'm very happy with it! The following weekend I was out shooting the making of a portfolio for a model and it was all out doors and I had some minor issues. I had the ZEBRA set to 95 IRE but in my next job I'll follow up the suggestions from Rick and work indoors with ZEBRAScat 70 and outdoors on 110 and workout some details in post. Eric let me apologise if I took way to long to unswer your question but I wanted to give you a better picture of the situation.
ciao
AA

BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
4.5GB RAM
1 TB OF MEMORY.
FCS 2
AJA KONA LHe




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Eric Lagerlof
Re: Zebra Levels (white very BRIGHT)
on Oct 15, 2008 at 4:30:23 am

And I'm getting back to you even later... Shooting events is always such a treat. Recently did a concert at a large theater and we preset the cameras to 3200k after a quick check with the lighting director. He didn't bother to mention that msot of the show his lights would be low and they would be using spotlights as the main lighting tool, xenon spotlights. Everybody blue...lovely.

Thanks for the response-continued good luck...

Eric L.



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Antonio Atzei
Re: Zebra Levels (white very BRIGHT)
on Oct 15, 2008 at 10:13:28 pm

Eric
I have a question if you woudn't mind give me your angle on it.
For some strange reason I have agreed (peer pressure)to shoot a wedding!!!! Just the thought it makes me uneasy (don't know why) maybe the fact that there's no chance for take 2 etc, or even better...
......... You know what I mean.
One crucial thing its exposure off course and this time I'll go on 70% ZEBRA as suggested to me earlier on then pull the mids out in post, my next point to avoid is the out of focus situation, I'm sure I will have time to put on focus but I thought that I may use the autofocus for that never to miss moment .... Maybe this it's only "FEAR OF THE UNKNOWN"........ ha ha ha
ciao

BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
4.5GB RAM
1 TB OF MEMORY.
FCS 2
AJA KONA LHe




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Rick Wise
Re: Zebra Levels (white very BRIGHT)
on Oct 15, 2008 at 11:10:23 pm

I suspect from your recent post, Antonio, that you have not understood suggested use of 70 and 100 Zebras. If you are shooting caucasian faces, and you set your Zebras to 70, and you adjust the exposure so that there is just a HINT of zebra on the faces, you will have good exposure for those faces. You may find, however, that if your subjects are in bright sunlight (or any right light) and the bride is wearing white (most likely she is) then adjusting exposure for the faces may make her dress bloom and loose detail. Depending on the dress and the bride, that could be good, but more likely will cause much post anguish.

Since you are so unsure, I'd suggest you turn everything to auto. Auto focus, auto exposure, even auto white balance. Concentrate on framing and catching those important moments over which the bride, groom, moms and pops will sob and cheer when they view it for the first time, before storing it away for another 50 years, when the survivors can once again pull it out and possibly see it again, though technology will be so different they probably cannot.

I am being a bit harsh here. However, having shot three weddings for free I have seen how, even though the initial screenings were greeted with genuine delight, these videos are just not looked at again. Probably the best purpose is for the bride and groom to see what actually went on (at least a part of it) since none of us can remember that great day without photographic help. When we were the bride and groom, we were just too deeply involved at the time.

A critical and difficult part of shooting a wedding is the audio. Unless you can put a radio mic on at least the groom, getting good sound will be very, very difficult. An alternative is to get yourself very close to them when they say the vows, and have a good or decent external mic on the top of your camera. The cheapest semi-decent solution I know of is the Rode Video Mic. (http://www.bhphotovideo.com/c/product/363083-REG/Rode_VIDEOMIC_VideoMic_Cam...) $150. If you are shooting outside, be sure to also get the "dead cat" wind muff.

Rick Wise
director of photography
Oakland, CA
http://www.RickWiseDP.com
email: Rick@RickWiseDP.com


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Antonio Atzei
Re: Zebra Levels (white very BRIGHT)
on Oct 16, 2008 at 1:15:21 am

Rick
Thank you once again for your very helpfull suggestion.

I may have explain myself not as good as I would have like it. My understanding was that to put it in a couple of words:

Work for the whites and if I need to pull out detail on faces I sure can do that in post, but you have raised another interesting point "the audio". And the photographer won't even let me have or ask to put a radio mic on anyone from the priest to the groom..... I think he wants keep control to show the Photographs as the best job, leaving the video as a secondary not very important job if you know what I mean................
well that why I love to make short films and not work full time in the industry... ha ha ha



BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
4.5GB RAM
1 TB OF MEMORY.
FCS 2
AJA KONA LHe




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Rick Wise
Re: Zebra Levels (white very BRIGHT)
on Oct 16, 2008 at 4:45:18 pm

If you are going to protect the hot spots (such as the bride's dress) manually, be sure to set the zebras to 100. Anything brighter than 100 will clip, loose detail. If you are getting zebras all over her dress, iris down (go to a higher number on the iris; the higher the number, the smaller the opening in the lens; an f11 is one stop smaller an opening than an f 8. An f 2 is pretty wide open, while f 22 is almost closed shut.)If there are just a few zebras on her dress, you are probably all right.

As I said, at least start in the auto iris position. On better video cameras you can toggle this on and off. Toggle it on, look at the picture. Then toggle it off and open/close the iris a bit to see if you like it better. The trouble is, the viewfinder is pretty low resolution, whether the sideboard LCD or the actual finder. Very hard to accurately judge exposure this way.

With all you have to do, and given your lack of experience, I think you are asking for extra trouble to try to adjust exposure manually except in extreme conditions, such as everything in the frame is "hot" except the bride and groom who are covered by a gazebo/roof. In such a case, you'd be better to let the hot part blow, and expose more for the bride and groom, though in such a case I'd underexpose them a little bit. This you would have to do manually. Alternatively, you could tighten the shot enough so that the couple fill most of the frame; in that case the auto iris will probably give you a decent exposure.



Rick Wise
director of photography
Oakland, CA
http://www.RickWiseDP.com
email: Rick@RickWiseDP.com


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Antonio Atzei
Re: Zebra Levels (white very BRIGHT)
on Oct 16, 2008 at 9:10:07 pm

Rick!

I like the idea of toggle between the two modes just to make sure. I'm ok with iris, depth of field, exposure etc, prob more from a photography point of view more then the camera. I had some doubts about the ZEBRA equivalent of: I hope I'm making myself understood
In the end I'll be able to fix few things in post that's for sure.

Although I'm getting paid for, it's more of an experiment. A year also ago I wrote and shoot/edited a low budget short film and believe it or not the story evolved around a wedding ceremony, and the dress came out ok but as I said before in short films yuo can have more then one take .... ha ha ha
Nonetheless I really apreciate your time and very clear explanations

Best Regards
Antonio

BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
4.5GB RAM
1 TB OF MEMORY.
FCS 2
AJA KONA LHe




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grinner hester
Re: Zebra Levels (white very BRIGHT)
on Sep 28, 2008 at 9:56:07 pm

I set zebras at 80 and look for em in hilights but never count on that being the finished exposure. I edit everything I shoot so I count on making it perfect in post later.



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Antonio Atzei
Re: Zebra Levels (white very BRIGHT)
on Nov 2, 2008 at 11:30:18 am

By the way....

The wedding was a couple of weeks ago and for what I know they're still married! Ha Ha Ha

I shoot all in manual and to aid the setting of WB I used a set of warm cards........ everything went ok

Txs for your suggestions

ciao
Antonio


BABALOTTI PRODUCTIONS
SYDNEY
POWER MAC G5 QUAD SYSTEM
4.5GB RAM
1 TB OF MEMORY.
FCS 2
AJA KONA LHe




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