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Old February 8th, 2008, 07:09 PM   #151
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Just for comparison and to show you what a pretty day it is today I post this sky shot that the camera says is exposed correctly but Vegas says it way over? Go figure?
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Old February 8th, 2008, 07:26 PM   #152
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Just for comparison and to show you what a pretty day it is today I post this sky shot that the camera says is exposed correctly but Vegas says it way over? Go figure?
Yeah that is over exposed a bit, look at the house.

Of course this is one of those circumstances when overexposure is aesthetic.

As far as the camera saying its OK, are you using the histogram or the spot meter?

Histograms can be very misleading in these circumstances. The spot meter wouldn't say a thing unless you zoomed in on the overexposed portions.

So I guess we are all learning that photographic technique has to be more refined when using this camera.

That and if you are gonna mess with PP's you better be a DIT in training.

Oh, and yeah- nice day. I hate you kindly from the Washington DC area. :)
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Old February 8th, 2008, 07:38 PM   #153
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Just for comparison and to show you what a pretty day it is today I post this sky shot that the camera says is exposed correctly but Vegas says it way over? Go figure?

This just in from Alaska....

YOU SUCK!

:-)
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Old February 8th, 2008, 07:55 PM   #154
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Yeah that is over exposed a bit, look at the house.

As far as the camera saying its OK, are you using the histogram or the spot meter?

Histograms can be very misleading in these circumstances. The spot meter wouldn't say a thing unless you zoomed in on the overexposed portions.

:)
One of the reasons I was so keen to get an EX1 was for the Histogram, but I have given up on it already. Here I was trying what Bill said when he objected to my 95% post and used the Zebra #2, the 100% one. I zoomed in on the snow that was the hot spot and stopped down until there were no zebras. I took another take by eye which was much better and which filled the Vegas Histogram nicely. I do believe in the hot light like I have to deal with (that camera was under a black tarp today just so I could see it) the EX1 over-exposes at 100%. I usually use Zebra 1 at 95% which is effectively 85%-105% which I find much better. Incidentally there was no tweaking with that image - just straight Cine4 with HiSat.
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Old February 8th, 2008, 10:01 PM   #155
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Vegas histogram

Where's the histogram in Vegas ?
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Old February 8th, 2008, 10:20 PM   #156
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It's under view called Video Scopes.
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Old February 9th, 2008, 05:18 AM   #157
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One of the reasons I was so keen to get an EX1 was for the Histogram, but I have given up on it already.
Now now... winners never quit.

The problem is that you don't understand either what Vegas's scopes or the camera's histogram are truly measuring- or how they relate to each other.

Sucks if the histogram is showing 115 IRE at the right edge and Vegas's scopes clip at 105IRE despite being labeld for 120 IRE.

(I don't use Vegas- I'm just making up numbers for discussion.)

Put differently we don't have confidence in our tools.

The only way to understand and gain confidence is to test test test.

To test effectively you need test subjects whose nature you understand very well. That's what these guys provide

Then you need some independent test tools. The simplest is a light meter. I think you need BOTH an incident meter and a spot meter. A good HARDWARE waveform/vectorscope combo is also a good idea. These two tools are MUCH more reliable than their software counterparts in the NLE or even in the camera.

Use consistent artificial lights. Ideally film lights. (Tungsten Fresnels are what I like to do my baseline testing with.) You also have to test in your studio. You can't control most environments- and you need control if you want to understand.

Now you can do some measured photography and record a bunch of information.

Analze all that and now you have the ability to understand what the various meters are saying, how they compare to each other- and what their various limitations are.

It takes time to do this right- and it takes even longer to learn what tests you should be doing and what they mean to your productions.
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Old February 9th, 2008, 08:11 AM   #158
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I usually use Zebra 1 at 95% which is effectively 85%-105% which I find much better.
Hi Michael, did you mean 90% to 100% (or if including Zebra B 90% to 105%)? My understanding was that zebra displays 5% above and below the selected target warning.

Also, any thoughts on if 100% zebra is supposed to equate to the far right of the EX histogram or if 108% is supposed to match the "255" reading. Apologies, no background with IRE, so trying to relate these tools to my realm.
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Old February 9th, 2008, 09:31 AM   #159
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Hi Michael, did you mean 90% to 100% (or if including Zebra B 90% to 105%)? My understanding was that zebra displays 5% above and below the selected target warning.

Also, any thoughts on if 100% zebra is supposed to equate to the far right of the EX histogram or if 108% is supposed to match the "255" reading. Apologies, no background with IRE, so trying to relate these tools to my realm.
Randy: A bit like asking the blind to lead the blind. I'm still fairly confused myself! As far as the Zebras go, Z2 is fixed at 100% out of a possible maximum of 108%. Z1 has a latitude of 10% so you are right that a setting of 85 means 80-90 but I don't understand how a cut-off point which is what a zebra is, can have a spread, unless they are referring to possible errors in the metering.

Someone with IRE knowledge need explain to many of us how the 10 stop luminance spread is related to the 108% and to the IRE scale. As I have said before when my camera shows a 100% exposure and the histogram is nicely filled, put that into Vegas and the spread is like -20 to 115 with cliping both ends. I have only shot three times so I still need lots of practice and the light has been very harsh here recently and seldom have I been able to see the LCD. Up and running by Easter I'm thinking.
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Old February 9th, 2008, 10:39 AM   #160
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I did a bit of testing by swithching Zebra A to 107, and comparing to the histogram for when the far right begins to register. Assuming that zebra would not kick in until 102%, that is occuruing before anything is showing at the far right of the Histogram. So it looks to me like 108% is what I am used to considering a 255 reading.
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Old February 9th, 2008, 01:43 PM   #161
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Maybe I just do not know how to use it effectively, but my advice would be to forget about the histogram. its a very general exposure tool that's pretty worthless for telling you exactly what's going on in your picture and especially for judging highlight exposure. its pretty normal to have something up at 100% or over, the important question is what and where and the histogram doesn't tell you.

Learn to use your zebras and your IRE readout in the viewfinder. Too bad this camera won't let you switch between 2 zebra settings.
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Old February 9th, 2008, 01:54 PM   #162
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You mean switch quickly without going into the menu ? Both zebras can be on at the same time.
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Old February 9th, 2008, 02:15 PM   #163
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Maybe I just do not know how to use it effectively, but my advice would be to forget about the histogram. its a very general exposure tool that's pretty worthless for telling you exactly what's going on in your picture and especially for judging highlight exposure.
Hi Leonard,
The Histogram can potentially be the most valuable tool. It will show you the brigtness distrubution of all pixels, rather than ones specified by a numeric brightness range or physical area. A larger histogram can tell you when you have blown highlights as well as any tool out there. As it stands, the EX histogram is too small for this, so its benefit seems limited to use in combination with the zebras. I have probably gone on too long about this as I am not unintentionally blowing highlights with this camera, but I do at times find myself being a bit conservative and if anything am tending to sightly underexpose a touch when in doubt.
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Old February 9th, 2008, 02:17 PM   #164
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I zoomed in on the snow that was the hot spot and stopped down until there were no zebras.
If you zoomed in, locked the exposure, then zoomed back out, I thought the lens opens a stop or more? Could this be why the shot was overexposed?
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Old February 9th, 2008, 04:11 PM   #165
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If you zoomed in, locked the exposure, then zoomed back out, I thought the lens opens a stop or more? Could this be why the shot was overexposed?

I thought this lens surely to be constant f. Can anyone confirm? The "spot" metering method I used is as suggested in the Vortex training video.
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