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-   -   White Balance Issue with XL-1 (https://www.dvinfo.net/forum/canon-xl1s-xl1-watchdog/1356-white-balance-issue-xl-1-a.html)

Greg Matty March 20th, 2002 11:52 PM

White Balance Issue with XL-1
 
I really enjoy using my XL-1 with one exception, getting a good white balance. I know I can color correct the video in post but I just assume not have to render an entire project if I can avoid it. Having said that, here is the situation as I have been unable to resolve it.

1) Why not just use the auto setting? For any single frame of video, this works great. The problem is that I can see subtle changes in the white balance as the camera records. I think the term "auto" should be changed to "continuously variable." It is especially noticeable outdoors when the colors are washed out. Also, if I did decide to just color correct the video, it needs to have a single white balance locked in or I will have to keyframe the color correction. Not acceptable.

2) Why not use the outdoor setting when outdoors? I try this but the colors all have a blue tint to them. There is a chance I have this backwards and the colors are on the yellow side but I think blue is correct. I have used this but end up having to color correct.

3) Why not use the indoor setting when shooting indoors? I set up my tota's and omni's with 3200k lamps which I think is the same rating as the XL-1's indoor setting. Unfortunately the colors are also off. My moderately tanned mug appears very pink in color. If I use this setting indoors I am forced to color correct. Sigh.

4) Why not set the balance manually with a white card? I have tried everything white in my posession from brand new t-shirts to the white walls to white poster board. I even had a red haired friend take his shirt off so I could use his back. I still get a white balance where colors appear cool/blue but it is better than 3 or 4 above. Someone suggested setting the white balance with a sheet of notebook paper. The idea was that the blue lines would alter the setting just enough to warm up the colors. This idea was no improvement over ordinary white objects. I then decided to place blue gels in front of the lens when I set the white balance. I have tried 1/8 blue, 1/4 blue, 1/3 blue and 1/2 blue individually, and paired up with one another. This subtracting blue light method helps, but is still not ideal. Should I also subtract a little green or magenta? I don't know.

Are there any white balance guru's that can help me get this figured out. I am being very picky about this but it shouldn't be this hard to do.

Thanks for any ideas.

Greg Matty

Ken Tanaka March 21st, 2002 12:19 AM

Hello Greg,

You're correct in observing that manual white balance is generally the only way to go. But your problem puzzles me. At least one person has reported drifting wb lately but I don't recall anyone reporting that they couldn't set it accurately at all. I'm sure others with more experience will chime in, but a few follow-up questions come to mind that may help folks narrow down the problem with you.
- Are you using the XL-1 or the XL1s? I know you indicated the former but often people will leave off the 's' inadvertently.

- Are you confident of the accuracy of the reference monitor you're using?

- Do you make any AE adjustments in your shots? If so, have you noticed any influence on your wb?

Bill Ravens March 21st, 2002 08:22 AM

I had the same problem until I used an 18% gray card placed flat in direct sunlight. I also run +1 on the color correction setting. Warms things up slightly without looking artificial.

Greg Matty March 21st, 2002 09:22 AM

- Are you using the XL-1 or the XL1s? I know you indicated the former but often people will leave off the 's' inadvertently.

I am using the XL-1, not the S. I wouldn't mind the upgrade though.



- Are you confident of the accuracy of the reference monitor you're using?
I plug my XL-1 into my Sony monitor. It is only a $500 monitor but I trust it to be accurate. The color bars appear correct so I assume the image I am getting is about right.


- Do you make any AE adjustments in your shots? If so, have you noticed any influence on your wb?

I don't use AE, just Final Cut Pro and Commotion. When I do color correction, I just use one of the RGB tools and make an the adjustment. FCP 3.0 has much more sophisticated color correction tools, but I have gotten good results with my other method. Certainly the improvement is there over the uncorrected footage.

Ken,

What do you think about the other gentlemens idea of using the 18% gray card? I don't know where to pick one up but I will try to find one.

I am being real picky here and it would be nice to have a Seattle area XL-1 users group to compare white balances.

Thanks to both of you for responding.

Greg Matty

Bill Ravens March 21st, 2002 09:57 AM

All still camera light meters are calibrated against 18% graycards, and I assume vidcam meters are as well. They're available at ANY photographic supply house/consumer camera store....pretty common fare.

Bill Ravens March 21st, 2002 10:32 AM

One more noteable point.....18% ray equals 45-50 IRE on a video
cam.

Ken Tanaka March 21st, 2002 10:41 AM

Greg,

Bill has a good suggestion and it's certainly going to be cheap to try. You should be able to get a calibrated grey card from any good photo shop (or online from reputable dealers such as B&H Photo.)

Alternately, if you have a pretty good inkjet or laserjet printer and Photoshop you might actually be able to print your own for free by creating a page-sized graphic flooded with an 18% grey "color", then print it at 100% scale.

-Ken-

Nathan Gifford March 21st, 2002 11:28 AM

18% Grey Card Only Way to Go.
 
18% grey (or gray??...what is it called in the Kingdom???) is the only way to go. Besides that, they are very cheap: darn near cheaper than tape!

One other problem you should be aware of it the the color temp of the lights in the area have a tremendous impact on color. That K rating and the CRI (I think that is correct--Color Reproduction Index) have everthing to do with good color under artifical light.

If the lighting in the area has a different color temp you will likely have some kind of problem. White balancing helps a lot and with the S multiple white balance settings that's a real plus. I wish my XL-1 had these multiple settings.

Nathan Gifford

Greg Matty March 21st, 2002 12:04 PM

Nathan,

I agree 100% with the XL-1s having multiple white balance settings. When I get this sorted out, I could set one for "indoors." When I use my 3200k tota's and omni's and don't mix any other light sourse, and one for outdoor sunny days. I could get them set and leave them that way. That would be nice.

I will check the net for an 18% gray card right now. Heck, I might even buy two of them.

Thanks for all the tips. Now if can just make some money on my Costa Rica/Belize video to buy a new camera.

Greg Matty
www.rk-productions.net

Ken Tanaka March 21st, 2002 12:17 PM

Costa Rica and Belize videos, eh? Gee, sounds like the idea market would be recreational scuba divers!

Greg Matty March 21st, 2002 12:21 PM

Ken,

Only a small section of the video was shot underwater. There are some nice images though. My distributor said it would take ninety days "to get orders." I am not sure what she meant but that time frame expires in three weeks. I hope she has some good news for me.

BTW, I just ordered my 18% gray card from Camerworld.com. B&H said they did not have such an item. Strange. But at least I got them.

Greg Matty

Charles Papert March 21st, 2002 12:42 PM

I have used standard white paper for years to white balance without problems, although a gray card will work great if you have one. A useful thing to have is a gel swatchbook, particularly the "Jungle Book" made by Rosco which is about 3" square, a good size to hold in front of the lens to "cheat" the white balance, and has all strengths of CTO, CTB and plus/minus green. I had a two-camera XL1 shoot last weekend, and we were able to balance the cameras very closely using a 1/4 blue and 1/8 minusgreen on one camera, with the other clean. Just remember that the effect will go the opposite direction of the gel--using a blue gel will correct the image more orange, using a magenta gel will turn it more green, etc.

In day exteriors, I prefer to balance in the shade, which will warm up the scene overall.

And yes, I too was wishing we had XL1s's, when we had to move from indoors to outdoors multiple times and do the white balance thing all over again. Tiresome!

fargograf March 21st, 2002 04:56 PM

Are there "meters" that tell you what the color temperature is, as well as the light intensity?

Vic Owen March 21st, 2002 07:10 PM

"I am being real picky here and it would be nice to have a Seattle area XL-1 users group to compare white balances. "

Shouldn't be a problem in Seattle -- everything has been grey for some time!

Check Glazer's (downtown off Mercer) -- they should have the cards.

Greg Matty March 21st, 2002 08:08 PM

<<<-- Originally posted by steadichupap : I have used standard white paper for years to white balance without problems, although a gray card will work great if you have one. A useful thing to have is a gel swatchbook, particularly the &quot;Jungle Book&quot; made by Rosco which is about 3&quot; square, a good size to hold in front of the lens to &quot;cheat&quot; the white balance, and has all strengths of CTO, CTB and plus/minus green. I had a two-camera XL1 shoot last weekend, and we were able to balance the cameras very closely using a 1/4 blue and 1/8 minusgreen on one camera, with the other clean. Just remember that the effect will go the opposite direction of the gel--using a blue gel will correct the image more orange, using a magenta gel will turn it more green, etc.

I have a rosco gel pack but it is more like 1" x 3". It won't cover the entire lens. I would love a 3"x3" for the reasons you mentioned. I will check with Northwest Theater Supply and see if they have a 1/8 minus green. Adding that to the 1/4 blue I already have might also help with this. BTW, what d CTO and CTB stand for?

Thanks for all the suggestions.

Greg Matty


In day exteriors, I prefer to balance in the shade, which will warm up the scene overall.

And yes, I too was wishing we had XL1s's, when we had to move from indoors to outdoors multiple times and do the white balance thing all over again. Tiresome! -->>>


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