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Exposure On The DVX-100

1st February 2004

Since we're all talking about exposures on the PD-150 being confusing I'd like to ask what people may have found about exposures on the DVX-100.

On the PD-150's, despite the LCD's unreliability, I usually have used the zebras....the 70% zebra often seems useful for getting people's faces in the right ballpark--say, a highlight reaching 70%--which is just a tad under what auto exposure brings you, which seems about right.

I've been shooting a show with the DVX-100 lately though and it's thrown all that method out. First, the zebras are not adjustable to anything under...is it 80%? secondly, what you get through auto exposure does not seem to work with zebras in the same way. in the PD-150 if you put auto exposure on a gray card, for example, it will end up entirely at 70%. But on the DVX-100 it seems like it not only doesn't go to 80% (don't know why they would set zebras at 80%!) but even seems to go to something darker than 70%.

Now, again, on PD-150's and even betas and DigiBeta s etc. it often seems that going a little darker than auto is good. On the DVX-100 though I'm quite confused. Get a 80% zebra on a facial highlight and then dial down til it's gone? I've really just been eyeballing it, which is a terrible method, though it has seemed to work adequately in most cases so far. What better methods are there?

thanks

Bryan Donnell
DoP LA USA


Bryan Donnell writes :

>Since we're all talking about exposures on the PD-150 being confusing >I'd like to ask what people may have found about exposures on the >DVX-100.

I just bought a DVX100 and a Century .07 wide angle lens and I must say I am not getting rid of my PD150.

Although the DVX100 has 40,000 more useful pixels and the mounted lens is nice, the camera may be more suited for those who are doing film outs or feature work.

I do TV and there are things that bother me, especially when I have to run and gun!

Exposure is one thing. I've set my iris at -1 and sometimes -2 but it's hard to get in the zone. Overall I think it can run a bit hot. It looks like it wants to compensate for back light more than I would like and the machine doesn't particularly like high contrast situations, which I am facing here in the southeast since winter is coming and the sun is lower in the sky thus giving me more harsh shadows and hard side light... which seems to confuse the auto iris.

Panasonic did a nice job in getting the bars right and easy to get to, but you still have to do jump through menu hoops to set the time code.

Speaking of time code, it looms at you at the top of your picture and seems to always be blocking the top part of my viewfinder where people are talking in my frame.

Audio is good but the metering system must be set up with a mixer. No db reference or scale.

And either it's a battery sucker or the Panasonic batteries are lame. I'm using the biggest ones they have and I go through 4 a day. That's why I have 6 and two chargers.

I'm liking the camera ok but it isn't the end all of DV...to me anyway.

I was going to wait until I finished shooting a few more weeks with it to write my opinion but I just thought I would respond to Bryan's query!

I'm going to give it more of a chance.

Allen S. Facemire
DP/Director
SaltRun Productions,inc.
Atlanta
www.saltrunproductions.com


>I've really just been eyeballing it, which is a terrible method, though it >has seemed to work adequately in most cases so far.

Actually, short of using a waveform monitor, that's the great thing about video - that you can eyeball your image until it looks good to you. Zebras are great as a guide, but it's the monitors and my sense of what looks good that guides me through my shoots. I personally only use zebras at 100 to let me know when I'm at risk of losing information and then I adjust accordingly. I expose as close to what I want to see in the finished product as possible, but I'm also aware of what can be done in post to bring it all into place if necessary.

Take a look at an article I wrote on exposing video in the 'articles' section of my website:

http://www.dancoplan.com

Dan Coplan
Cinematographer/Editor/DVD Authoring


Some thoughts on Dan's post :

>Actually, short of using a waveform monitor, that's the great thing about >video - that you can eyeball your image until it looks good to you.

Granted, your monitor is properly adjusted for bars.

>I personally only use zebras at 100 to let me know when I'm at risk of >losing information and then I adjust accordingly.

Two schools here and neither is wrong.

Dan's side says that anything over 100 is garbage so if zebras tell you what garbage is, then good. Why have to worry about anything over 100 since it's white anyway regardless of who it looks to you and everything less has the possibility of showing up.

Personally, it's always faces that mater to me so zebras for me zebras must be between 70-80 on these little guys considering the format needs all the help it can get. Look at it this way, with a person with a bright background and your camera set at 100ire, you'll know when the sky is gone, but the face might be lost somewhere in there and without both my eye to see that and zebras to confirm it, I could loose both or end up with something I really don't want. With the zebras at 70-80ire, you'll know when the faces are starting to turn to crap, and at that point since your background is brighter, who cares about the sky, I know I am going to loose something just as long as it isn't the faces.

Walter Graff
Producer, Director, Creative Director, Cinematographer
HellGate Pictures, Inc.
BlueSky, LLC
www.film-and-video.com


The AG-DVX100 has zebras which can be set at 80, 85, 90, 95 and 100 IRE. They are located in the Display Setup menu.

I believe the factory defaults for Zebra 1 is 80 IRE and Zebra 2 is 100 IRE, but they can be adjusted to any of the above values. I normally use one set of Zebras set to 100 IRE and use that to set exposures.

Why do consumer cameras' Zebra settings normally only go as low as 80 IRE? 70 IRE (or better yet, 55 or 60 IRE) would be so much more helpful.

Jessica Gallant
Los Angeles based Director of Photography
West Coast Systems Administrator, Cinematography Mailing List
https://cinematography.net/


>Why do consumer cameras' Zebra settings normally only go as low as >80 IRE? 70 IRE (or better yet, 55 or 60 IRE) would be so much more >helpful.

My thinking is that zebras need not go lower because facial exposures above 80 are over exposed but anything below is okay so they made it the threshold.

Walter Graff
Producer, Director, Creative Director, Cinematographer
HellGate Pictures, Inc.


Sign me up for the 70 ire school of exposure...that's about as high as I ever want to see them. After that faces are getting over exposed and ready to lose tonal color.

I'm with Jessica...why in all get out would a manufacturer limit the zebra to 80ire ..... we used 100ire zebra all the time with tube cameras to keep from blooming and stuff. Setting the white clip @ 103 is fine for the highs.

But I want to reference a matching exposure on the face shot to shot as appropriate and 70 ire is the fast run and gun way to do that.

So OK.... here's the plan. We all meet at the town square at sunset and then we march together, a sea of torches blazing up the hill to the Baron's castle to demand 70ire settings for the villagers.

Al Emer
Lighting Cameraman
Holmdel NJ


Alan,

Which batteries are you using? CGR-D53 5800mAh?

Regards,
Marten


>So OK.... here's the plan. We all meet at the town square at sunset and >then we march together, a sea of torches blazing up the hill to the >Baron's castle to demand 70ire settings for the villagers.

Make sure the torches don't clip.

Art Adams, DP
Mountain View, California - "Silicon Valley"
http://www.artadams.net/


>With the zebras at 70-80ire, you'll know when the faces are starting to >turn to crap, and at that point since your background is brighter...

I belong to the "set it at 100" school. I used to use zebras for faces until it dawned on me that flesh tones are all over the place and shouldn't always be exposed the same way (or at least that's my taste and preference.) With zebras at 100 I can make an informed decision as to how much of the sky I'm going to throw away to save the face.

I figure that as long as my viewfinder is set up to bars and I can see where I'm clipping the faces will end up just fine.

So far so good, although it's been a long time since I've had to work without a monitor handy.

Art Adams, DP
Mountain View, California - "Silicon Valley"


>With zebras at 100 I can make an informed decision as to how much of >the sky I'm going to throw away to save the face.

That makes sense to me on a real camera shooting a real format but on a DV camera you simply don't have enough room to really make it work as the original poster learned the hard way.

>I figure that as long as my viewfinder is set up to bars and I can see where >I'm clipping the faces will end up just fine.

And that is the reason why the rule has one variable that makes it difficult to say right or wrong. For one with lesser formats you have lesser headroom so a mistake is more difficult, or easier because as I see it you are either off and it all shows as a big mistake or your in the safe range and it all works fine. Since that range is less, the idea of one small area being off from another doesn't exist as much as more robust formats and cameras.

I see a big difference between the possibilities of individual subtleties with more expensive formats and hence why zebras to me for DV really make no difference at all. My reference to zebras is for more robust formats and I probably should have made that clear. Second, I have extensive experience with video as others such as yourself do. I could tell you exposure from standing three feet looking at a 4 inch LCD as many others here can too.

For some who have less experience, they require more information to understand how it all works and for others who do it every day, it's more second nature since we have more experience.

The original poster did nothing wrong. It just sounds to me like he has less experience and learned a lesson. I did that many times too, which is why I now know video exposure better than the those who haven't experienced it enough or haven't screwed it up enough. It took me at least five years of daily use before I could really say I understood video exposure. With today's 1/3 inch chips, less than great formats which have somehow become professional, with their cheap lenses, plastic cases, and flip out LCD viewfinders, etc, it's an even tougher proposition. Every now and then we have to step back and realize it's only DV.

Walter Graff
Producer, Director, Creative Director, Cinematographer
HellGate Pictures, Inc.


Well, I'm a big fan of dual zebras as it gives me more information...and more is better! (Of course I'm often shooting docs without time for a monitor, so that's an important variable.)

But my experience is that digital tape formats (yeah it's a big generalization, and what Walter calls "more robust formats" aren't as bad) are less forgiving of overexposure on flesh tones than analog formats.

So "flesh tone" has become more important for me, because of this.

George Hupka
Director/DP
Downstream Pictures
Saskatoon, Canada


> which seems to confuse the auto iris.

Did you say, "auto iris"?

>Speaking of time code, it looms at you at the top of your picture

Open the flip out screen and push the "counter" button until it goes away.

>Audio is good but the metering system must be set up with a mixer. No >db reference or scale.

Yeah, this is lame, but spend some time with a mixer figuring out which "dot" refers to which dB level and you should be all set. Or maybe somebody already knows? Anyone?

My biggest complaint with the audio is that there's no automatic audio level option. As much as I opt for full manual, it's during those run-'n-gun situations that I can't be troubled to constantly be dialling the levels up and down, not to mention the impracticality.

>And either it's a battery sucker or the Panasonic batteries are lame.

Yes! This is the worst part. I have a battery for my Sony that's approximately the same size, lasts 7 hrs. + AND tells you in the camera's display exactly how much time is left!

Are you listening Panasonic?

Otherwise, I love the camera and personally, wouldn't touch any other camera in its class.

Dan Coplan
Cinematographer/Editor/DVD Authoring


>Which batteries are you using? CGR-D53 5800mAh?

I'm using two "CGP-D28s, 7.2V, 2800Ah" batteries and they last me a whole day (12h) with the camera in permanent standby at room temp. and the flip out LCD on.

Sometimes even both the LCD and the viewfinder on. I keep the Battery that came with the camera as a backup and hardly ever use it.

This one really drains fast though.

Best Wishes

Daniel P. Loher
Director of Photography
Munich based


Dan Coplan wrote:

>My biggest complaint with the audio is that there's no automatic audio >level option.

I was under the impression that the audio had a limiter function. At least it feels that way to me.

Steven Gladstone
Cinematographer - Gladstone Films
Cinematography Mailing List - East Coast List Administrator
Better off Broadcast (B.O.B.)
New York, U.S.A.


> I was under the impression that the audio had a limiter function.

It does have a limiter function but it doesn't have automatic gain control.

Dan Coplan
Cinematographer/Editor/DVD Authoring


If you press the zebra button three times (and click your heels) you'll get a small pair of brackets in the viewfinder with an indication of the IRE of whatever is in those brackets. 80 IRE or not, the camera will give an accurate reading of any face you may be shooting, shot to shot.

Brian Galford
WriterDirectorShooter
(not necessarily in that order)
Sharon, MA


Brian Galford

>f you press the zebra button three times (and click your heels) you'll get >a small pair of brackets in the viewfinder with an indication of the IRE of >whatever is in those brackets.

Yes, I love this spotmeter function on Panasonic cameras. I was so happy when I discovered they included it on the DVX100. I often find this to be more useful that zebras or sometimes even a waveform where one has to weed out all the other info to find what one really wants to know at the moment.

Mitch Gross
NYC DP


>I was under the impression that the audio had a limiter function

The audio limiter function is put on when the "volume" buttons are set into the middle. They kind of snap into place.

As Dan says, that’s just the limiter- there's no auto gain from what I know.

All the best

Daniel P. Loher
Director of Photography
Munich based



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