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A question having something to do with Color Bars


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#1 David Calson

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Posted 11 October 2006 - 09:51 PM

I make videos for this company. The lighting looks great through the viewfinder and when I export it as a file. When the company gets it they say it looks overwhelmingly dark. I see the work that I did when its put on their site, and yes it looks incredibly dark. What do I do? Thanks in advance.
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#2 Tim J Durham

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Posted 11 October 2006 - 09:59 PM

I make videos for this company. The lighting looks great through the viewfinder and when I export it as a file. When the company gets it they say it looks overwhelmingly dark. I see the work that I did when its put on their site, and yes it looks incredibly dark. What do I do? Thanks in advance.


You'll need to describe your workflow in more detail.
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#3 David Calson

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Posted 11 October 2006 - 10:03 PM

sorry, what exactly do you mean by 'workflow'?
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#4 Tim J Durham

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Posted 11 October 2006 - 10:21 PM

sorry, what exactly do you mean by 'workflow'?

How did you get it from your camera to your boss?
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#5 David Calson

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Posted 11 October 2006 - 10:24 PM

How did you get it from your camera to your boss?


Oh, I export it to a quicktime file, burn on DVD. Ship it to him.
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#6 Tim J Durham

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Posted 11 October 2006 - 10:35 PM

Oh, I export it to a quicktime file, burn on DVD. Ship it to him.

So you're saying the Quicktime file looks good on your computer? Do you have an NTSC preview monitor? How are you doing the compression for DVD? With Compressor? DVD Stu Pro?

Detail the steps you take from the shoot to the dvd output EXACTLY and people may be able to tell you where you went wrong, otherwise it's just guessing.
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#7 David Calson

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Posted 11 October 2006 - 10:45 PM

So you're saying the Quicktime file looks good on your computer? Do you have an NTSC preview monitor? How are you doing the compression for DVD? With Compressor? DVD Stu Pro?

Detail the steps you take from the shoot to the dvd output EXACTLY and people may be able to tell you where you went wrong, otherwise it's just guessing.



Yes and on my camera. No NTSC preview monitor. I compress using premiere pro's Sorenson Video 3 compressor.

Details: Open viewfinder, set the f/stop so nothing is overexposed/underexposed. Plug in camera to PC with firewire. Use premiere's capture window. Put it on the NLE timeline. Shorten/lengthen footage accordingly. Export as a quicktime file using Sorenson 3. Burn. Play on computer. Looks just like on viewfinder.
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#8 ryan_bennett

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Posted 11 October 2006 - 10:51 PM

Do you use a waveform monitor in premiere at all or zebra stripes? Maybe a link to one of the videos would be nice.
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#9 Chad Stockfleth

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Posted 11 October 2006 - 11:30 PM

Without an NTSC monitor set up correctly for bars and using a waveform monitor, you aren't going to be able to accurately predict what it will look like. The viewfinder on your camera as well as your computer monitor could be overly bright, etc. Following those guidelines, starting when you shoot and continuing through your post workflow is the only way to know things are proper on YOUR end.

Everyone's viewfinder, monitor, tv what have you are going to look different. Contrast, saturation, brightness and even cropping are all affected.

Now what are they doing once they get the dvd? How are they posting it to the web? Is the problem something THEY are doing?

All things to take into account.

Hope you figure it out.

Edited by Chad Stockfleth, 11 October 2006 - 11:33 PM.

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#10 Bruce Greene

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Posted 11 October 2006 - 11:48 PM

I make videos for this company. The lighting looks great through the viewfinder and when I export it as a file. When the company gets it they say it looks overwhelmingly dark. I see the work that I did when its put on their site, and yes it looks incredibly dark. What do I do? Thanks in advance.


Good news, your problem has nothing to do with color bars :)

You have two variables:

1. The calibration of your computer monitor vs. the calibration of your customer's monitor.

There are firstly the brightness/contrast controls of the monitors themselves, they could be very different. Also there are two common gamma setttings for computer monitors. Macs come from the factory set to gamma 1.8 and all others set to 2.2. A file that looks good on a 1.8 monitor will look darker on a 2.2 monitor. Note that Macs can be set to 2.2 in the control panel.

So if you're on a mac set to gamma 1.8, the quicktime file may look normal on your monitor but darker on your client's monitor if it's set to gamma 2.2

2. There is something about compressing into sorensen 3 that makes the compressed file darker. I've noticed this before and found that I need to lighten the video clip before making the compression via sorrenson 3.

Hope this helps. Note that since you're producing a quicktime for computer viewing, you don't need an NTSC monitor to adjust the color/brightness. You should have a properly calibrated computer monitor though. You can buy a special instrument to calibrate your computer monitor for between $100-$300.

And lastly, you could be using a cheap LCD monitor or laptop that changes brightness when you move your head. Don't use one of these for judging images. :angry:
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#11 David Calson

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Posted 12 October 2006 - 12:28 AM

Good news, your problem has nothing to do with color bars :)

You have two variables:

1. The calibration of your computer monitor vs. the calibration of your customer's monitor.

There are firstly the brightness/contrast controls of the monitors themselves, they could be very different. Also there are two common gamma setttings for computer monitors. Macs come from the factory set to gamma 1.8 and all others set to 2.2. A file that looks good on a 1.8 monitor will look darker on a 2.2 monitor. Note that Macs can be set to 2.2 in the control panel.

So if you're on a mac set to gamma 1.8, the quicktime file may look normal on your monitor but darker on your client's monitor if it's set to gamma 2.2



Whoa, I never thought of that. Thanks Bruce. So he's too dark and I'm average-too bright. I'm guessing the solution is, switch to his gamma and then adjust the brightness accordingly? Thanks everyone else for your responses, I learned alot.
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#12 Michael Collier

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Posted 12 October 2006 - 12:39 AM

Also keep in mind that some systems base video at 7.5 IRE, some at 0. If your final solution is based for TV, it should be at 7.5 (all values below it are used for calibration. the true broadcast range is 7.5-100) with computers, the base is always 0 (a technical issue pertaining to the difference between NTSC and RGB color monitors. Keep in mind NTSC was made standard in 1953, and updated last in 1960-something. 64 I believe.) this may not be your problem, but if your unsure what your camera was set to, and what your edit bay was set to, you have a lot of googling to do (which is good, cause google has about 1.6 billion to make up for recent purchases)
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#13 David Cox

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Posted 12 October 2006 - 06:20 PM

Here's a really unscientific way to check your computer monitors brightness against the real world.

Go watch your normal TV set and check that what you are seeing looks kind of about right. Now play your camera footage into your TV using a video lead. Park on a decent frame that you have already captured by firewire into your computer. Now look at the frame on your TV coming from the video output of your camera and the image of your firewire captured stuff on your computer. They should look about the same in terms of brightness. From what you have said and others have commented, you might find that your computer monitor makes the images look a lot brighter than they really are. If this is the case, you will see a big difference in the brightness of the image between your computer screen and your TV.

This is really unscientific because it is comparing two completely different signal paths, but assuming you are not in the habit of watching your TV really bright, then it should at least give an indication.

Here's a slightly more scientific way to roughly set up your monitors. It does brightness, contrast and colour saturation but not gamma. Make two boxes on the screen in any simple graphics package. Fill one with black (0,0,0 RGB) and the other with a little lighter than black (5%,5%,5% RGB). Turn your monitor brightness up and then bring it down slowly until you get to THE point where your black box no longer gets darker but you can see that the other box is JUST lighter. You have now set your black levels. Now repeat with a white box (100%,100%,100% RGB) and an off white box (95%,95%,95%). Now turn your monitor contrast right down and then slowly up until the white box doesn't get any lighter but you can still see the other box is a little darker. You have now set the white level. Do the same with a 100% red box and a 95% red box and do the same trick with the colour saturation.

After all these three, you will have matched the range of your monitor to the range of the signal you are going to send it. This is a rough but reasonable calibration for a domestic monitor in good working order. Of course if it is yellowing with age or covered in dust, these tests cannot take account of that!

David Cox
Baraka Post Production
www.baraka.co.uk
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