Trouble in the Reds with 3200k lighting at DVinfo.net

David Morgan · March 15th, 2008, 08:32 PM

I'm consistently having an issue with resolving red. I shoot a lot of theatre shows. All colors (blue, green, yellow) look fine while recording (although the over all look is a little bit on the cold side).

However, the reds are consistently going toward blue so I end up with a magenta instead of the rich saturated red that I'm looking at on stage. I white balance before each show.
In post, if I try to tweak the color balance or adjust the red hue, the rest of the colors go away from their true hue.

Anyone have any suggestions? Should I kick the red drive up on the custom setup etc....?
thx

Bob Hart · March 16th, 2008, 02:02 AM

If my fading memory serves, some live theatre lighting is a mix of three primary colour filtered lamps to produce white light.

Rather than use the camera 3200K preset, I would manually white balance to reflectance from the main spotlighting. You may be otherwise killing off the reds.

Giroud Francois · March 16th, 2008, 05:59 AM

3200k light means halogen light. Halogen is throwing A LOT of infrared as well.
look here
http://www.dvinfo.net/conf/showthread.php?t=117058

Seems that CMOS sensor have a little problem here (users from RED, HV20 and EX1 have all posted about this problem) and the Cold mirror filter should be part of the standard equipement.

David Morgan · March 16th, 2008, 11:09 AM

I used to have a couple of B + K filters for my Canon GL-2. U think this brand would be the best choice for the A1? I don't want to affect the sharpness of my images.

Bill Engeler · March 16th, 2008, 02:21 PM

Hi David -

You mentioned that the overall look was a little cold. How did you white balance? Could you possibly be balancing to an unusual configuration?

Have you tried setting the WB by dialing in Kelvin numbers until it looks good in the monitor or viewfinder? I'm not sure that WB is the problem, but we shouldn't rule anything out.

That said, the A1 does have a bias to magenta. You will notice that some of the custom presets try to compensate for that, by either boosting the green and red, or more complicated color matrix settings. You have to try these in realistic conditions, though.

I have no idea if an infrared filter would help, but I have some doubts, since first the A1 doesn't have a CMOS sensor, and also because the problems reported in the previous link are that some people have too much red, not your problem.

I have come to believe that there are some colors that the A1 will never reproduce faithfully, particularly burgundy red. There is a wall in my house of this color. I often shoot tests against it, and it very often comes out to the pinkish side. The VIVIDRGB preset seems to solve the problem to a great extent, but only in daylight. Under incandescent lights this preset is unusable.

The faces of the actors are the main thing, and if they look good, that's what's important.

David Morgan · March 16th, 2008, 05:13 PM

thx to all for the reply's.

bill, I know what u mean about faces but when the people in the show buy the DVD, they sure are gonna notice that the red shirts are now magenta. It's like, wow, that's not the shirt i wore in the show!! It's that much of a drastic difference.
I've tried cropping in on the shirt in post and changing the hue. very little success. If I look at the shirt via a vectorscope, it's shifted toward magenta. Can't seem to change it to red either.
This is starting to become an issue.

Jonathan Shaw · March 18th, 2008, 10:13 PM

What are you using for colour correction? I would be surprised if you can't correct this successfully in post.

Jon

David Morgan · March 19th, 2008, 07:34 AM

Final cut suite 5.1

Jonathan Shaw · March 19th, 2008, 10:12 PM

Ok can you post some raw footage and we can offer some advice or actually colour correct it. I work with most underwater footage which normally needs a fair amount of correction. Do you use the 3 way colour corrector and white and black balance in FCP?

Jon

Jack Jenkins · March 20th, 2008, 12:47 AM

No, 3200k does not mean Halogen, it refers to the color temperature, 3200 degres kelvin. Therefore it doesnt have to be halogen. It can be flourescent, incandescent or tungsten filament or in fact anything that emits 3200k color temperature light.

David are you positive that the 'white" lights being used are 3200 degrees?
Are they fresh 3200k bulbs?
My limited experience with theatre lighting did not involve photo-balanced lighting, ie: 3200k etc.. it was all perceptual lighting ie: whatever we could get our hands on. Remember, even 3400k lights start to look blue when using a 3200k setting. Another issue might be that one source is not 3200k and is throwing off the color. Also some minor color distortion can happen if the 3200k bulbs are old, this usually results in a yellower light though.

The 3200k setting on the cam must be used specifically with 3200k lights to ensure correct colors. Just as the sunlight (5000k) setting makes the colors look right under bright sunlight (5000k).

Check the bulbs, I have used the cam at the 3200k setting under 3200k bulbs and the colors look right.

Korey Kirschenmann · March 21st, 2008, 01:12 PM

The white balance is definitely one of the keys to the issue. However even if the camera is white balanced perfectly there still can be colors that are hard to reproduce in the A1 and/or any camera. One of the examples I have is purple. I can get purple to look purple but in doing so with any of the standard 9 presets and using white balance both auto, manual, and using K, the other colors tend to sacrifice to get purple. I am still playing but what I would recommend is you are going to have to play with the Presets and try all that are out there on the DV forums in combination with your white balance and if none work, then you may need to adjust them yourself.

Korey Kirschenmann · March 21st, 2008, 01:40 PM

In case you haven't tried the True Color preset, you may want to give that a try and see. Make sure to white balance again afterwards if you decide to try other options beside the K options.

The thread on True Color is here:
http://dvinfo.net/conf/showthread.php?t=116993&page=1

David Morgan · March 28th, 2008, 08:31 AM

thx to all for the reply's.

I manually balanced to a white reflector (the one's that have wire rims and fold up in a bag). So I didn't use the preset 3200k. I guess it's possible that the lights weren't all the same. I'm going to talk to the lighting guy about it.

David Morgan · March 28th, 2008, 08:42 AM

ps,
thx for the link to True Color. Will try it.

March 15th, 2008, 08:32 PM	#1
David Morgan Major Player Join Date: Oct 2006 Location: Burbank CA Posts: 466	Trouble in the Reds with 3200k lighting I'm consistently having an issue with resolving red. I shoot a lot of theatre shows. All colors (blue, green, yellow) look fine while recording (although the over all look is a little bit on the cold side). However, the reds are consistently going toward blue so I end up with a magenta instead of the rich saturated red that I'm looking at on stage. I white balance before each show. In post, if I try to tweak the color balance or adjust the red hue, the rest of the colors go away from their true hue. Anyone have any suggestions? Should I kick the red drive up on the custom setup etc....? thx

March 16th, 2008, 05:59 AM	#3
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	3200k light means halogen light. Halogen is throwing A LOT of infrared as well. look here http://www.dvinfo.net/conf/showthread.php?t=117058 Seems that CMOS sensor have a little problem here (users from RED, HV20 and EX1 have all posted about this problem) and the Cold mirror filter should be part of the standard equipement. Last edited by Giroud Francois; March 16th, 2008 at 01:55 PM.

March 18th, 2008, 10:13 PM	#7
Jonathan Shaw Major Player Join Date: Nov 2007 Location: Sydney Posts: 552	What are you using for colour correction? I would be surprised if you can't correct this successfully in post. Jon __________________ www.ginclearfilm.com www.facebook.com/ginclearfilm

March 19th, 2008, 10:12 PM	#9
Jonathan Shaw Major Player Join Date: Nov 2007 Location: Sydney Posts: 552	Ok can you post some raw footage and we can offer some advice or actually colour correct it. I work with most underwater footage which normally needs a fair amount of correction. Do you use the 3 way colour corrector and white and black balance in FCP? Jon __________________ www.ginclearfilm.com www.facebook.com/ginclearfilm

March 21st, 2008, 01:12 PM	#11
Korey Kirschenmann New Boot Join Date: Jan 2008 Location: Fargo ND Posts: 15	Preset + white balance The white balance is definitely one of the keys to the issue. However even if the camera is white balanced perfectly there still can be colors that are hard to reproduce in the A1 and/or any camera. One of the examples I have is purple. I can get purple to look purple but in doing so with any of the standard 9 presets and using white balance both auto, manual, and using K, the other colors tend to sacrifice to get purple. I am still playing but what I would recommend is you are going to have to play with the Presets and try all that are out there on the DV forums in combination with your white balance and if none work, then you may need to adjust them yourself.

March 16th, 2008, 02:02 AM	#2
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	If my fading memory serves, some live theatre lighting is a mix of three primary colour filtered lamps to produce white light. Rather than use the camera 3200K preset, I would manually white balance to reflectance from the main spotlighting. You may be otherwise killing off the reds.

March 16th, 2008, 11:09 AM	#4
David Morgan Major Player Join Date: Oct 2006 Location: Burbank CA Posts: 466	I used to have a couple of B + K filters for my Canon GL-2. U think this brand would be the best choice for the A1? I don't want to affect the sharpness of my images.

March 16th, 2008, 02:21 PM	#5
Bill Engeler Regular Crew Join Date: Aug 2006 Location: Brussels, Belgium Posts: 162	Hi David - You mentioned that the overall look was a little cold. How did you white balance? Could you possibly be balancing to an unusual configuration? Have you tried setting the WB by dialing in Kelvin numbers until it looks good in the monitor or viewfinder? I'm not sure that WB is the problem, but we shouldn't rule anything out. That said, the A1 does have a bias to magenta. You will notice that some of the custom presets try to compensate for that, by either boosting the green and red, or more complicated color matrix settings. You have to try these in realistic conditions, though. I have no idea if an infrared filter would help, but I have some doubts, since first the A1 doesn't have a CMOS sensor, and also because the problems reported in the previous link are that some people have too much red, not your problem. I have come to believe that there are some colors that the A1 will never reproduce faithfully, particularly burgundy red. There is a wall in my house of this color. I often shoot tests against it, and it very often comes out to the pinkish side. The VIVIDRGB preset seems to solve the problem to a great extent, but only in daylight. Under incandescent lights this preset is unusable. The faces of the actors are the main thing, and if they look good, that's what's important.

March 16th, 2008, 05:13 PM	#6
David Morgan Major Player Join Date: Oct 2006 Location: Burbank CA Posts: 466	thx to all for the reply's. bill, I know what u mean about faces but when the people in the show buy the DVD, they sure are gonna notice that the red shirts are now magenta. It's like, wow, that's not the shirt i wore in the show!! It's that much of a drastic difference. I've tried cropping in on the shirt in post and changing the hue. very little success. If I look at the shirt via a vectorscope, it's shifted toward magenta. Can't seem to change it to red either. This is starting to become an issue.

March 19th, 2008, 07:34 AM	#8
David Morgan Major Player Join Date: Oct 2006 Location: Burbank CA Posts: 466	Final cut suite 5.1

March 20th, 2008, 12:47 AM	#10
Jack Jenkins Regular Crew Join Date: Jun 2006 Location: Austin, TX Posts: 122	No, 3200k does not mean Halogen, it refers to the color temperature, 3200 degres kelvin. Therefore it doesnt have to be halogen. It can be flourescent, incandescent or tungsten filament or in fact anything that emits 3200k color temperature light. David are you positive that the 'white" lights being used are 3200 degrees? Are they fresh 3200k bulbs? My limited experience with theatre lighting did not involve photo-balanced lighting, ie: 3200k etc.. it was all perceptual lighting ie: whatever we could get our hands on. Remember, even 3400k lights start to look blue when using a 3200k setting. Another issue might be that one source is not 3200k and is throwing off the color. Also some minor color distortion can happen if the 3200k bulbs are old, this usually results in a yellower light though. The 3200k setting on the cam must be used specifically with 3200k lights to ensure correct colors. Just as the sunlight (5000k) setting makes the colors look right under bright sunlight (5000k). Check the bulbs, I have used the cam at the 3200k setting under 3200k bulbs and the colors look right.

March 21st, 2008, 01:40 PM	#12
Korey Kirschenmann New Boot Join Date: Jan 2008 Location: Fargo ND Posts: 15	Try True Color In case you haven't tried the True Color preset, you may want to give that a try and see. Make sure to white balance again afterwards if you decide to try other options beside the K options. The thread on True Color is here: http://dvinfo.net/conf/showthread.php?t=116993&page=1

March 28th, 2008, 08:31 AM	#13
David Morgan Major Player Join Date: Oct 2006 Location: Burbank CA Posts: 466	thx to all for the reply's. I manually balanced to a white reflector (the one's that have wire rims and fold up in a bag). So I didn't use the preset 3200k. I guess it's possible that the lights weren't all the same. I'm going to talk to the lighting guy about it.

March 28th, 2008, 08:42 AM	#14
David Morgan Major Player Join Date: Oct 2006 Location: Burbank CA Posts: 466	ps, thx for the link to True Color. Will try it.