White balance setting in camera when using flash gels

<p>Hi, what white balance setting do you use in your camera when you're using gels with flash? Do you set the white balance to auto or a certain color temperature depending on the ambient lighting? I usually take a photo of a 18% gray card which I use later in ACR for white balance correction. When using gels, how should I take the photo of the gray card - with the gel on or off? Thanks for your inputs.</p>

<p>I use auto white balance since I capture 100% RAW that's one ingredient I can correct in Bridge.</p>

<p>If you capture in RAW this can be postponed. I primary do weddings which is pretty fast paced, a variety of locations and lighting.</p>

<p> </p>

<p>if you're shooting in some tacky nightclub that uses lots of different coloured flourscent lights, you can use a window green (or 3/4 window green, salt to taste) on the flash and set your camera white balance to florescent<br>

if you're shooting indoors, say a wedding reception with lots of tungsen, CTO your flash and set white balance to that.<br>

however, it really depends on the amount of ambient you're working with, since you could be shooting a scene where tungsen and floroscent are all over the place, in which case you'd first want to see which ambient light sourse is more dominant. if tungsen is more major, CTO your flash and balance for that. there will be some colours being off due to flouroscent and there're two major solutions i use, both with their own pros and cons<br>

1. lower the ratio of ambient vs. flash. if you key with flash, you could up the shutter speed (limited to your camera's sync speed) to let the flash become more dominant. it may be necessary to close down your aperture and up the flash power/distance, each having their own impact on the overall lighting<br>

2. on top of #1, i've tried to gel the flash at 3/4 CTO and put my white balance to that (using temperature values) to success in SOME cases. this is the sketchy way to make a mid-way between the ambient flouro and tungsen. these two methods are more likely to succeed if you fill with ambient and key with flash since you're colour corrected to the dominant light source.<br>

3. more slaves - add a slave flash to the tungsen light source with a full CTO, out of sight (so it 'becomes' tengsen). CTO your main flash, then balance for that. you might need to heavily soften out/gobbo the slave flash to mimic the original tungsen light source. you are now able to 'control' the ambient tungsen light source via aperture and shutter speed and the slaved 'tungsen' light via aperture and flash power. doing things this way means overpowering/ reducing the effects of the flouroscent, stopping it throwing off your colours instead of trying to find an incompetent middle ground.<br>

further more, shoot in RAW. auto white balance only really works when there's a single dominant, identifiable light source, but there're often too many curveballs to throw it off chart.</p>

<p>Mr. Marks: short answer - grey card picture under the circumstances you're going to photograph everything else. So with the flash gelled. </p>

<p>I just did a blog post on this about my process from a shoot I did a couple of weeks ago: <a href="http://blog.aperryproductions.com/2010/02/white-balance-and-gelled-flashes.html">http://blog.aperryproductions.com/2010/02/white-balance-and-gelled-flashes.html</a></p>

<p>Alex, that was a good article. Thanks!</p>

<p>Alex, do you leave your camera white balance setting to auto? I assume you're capturing in RAW.</p>

<p>Mr. Marks, no I usually set it to custom WB based on the target that I shoot. I like everything to be consistent all the way through. I do shoot in RAW, so all can be adjusted later if a few are off because of a more dominant light source. If things aren't looking quite right I'll use the master WB grid adjustment to fine tune it. Theoretically, I could just shoot AWB and have the extra information of the camera. It's all personal preference. I sometime shoot events where I don't have the luxury of working in RAW as some clients want the JPEGS immediately, so if I shoot like this, I'm always prepared. </p>

<p>When I use a gel, I set my white balance manually. I choose a K temp and use that. Normally, I just use auto white balance because I shoot RAW and fine tune white balance in post. If you are using a gray card to get a custom white balance, you should have the gels in place before taking the reading. If you shoot RAW, you could just use the camera's presets as they will get you close enough.</p>

<p>What is CTO/CTS?</p>

<p>I always thought CT stood for color temperature. The O is orange. The S is straw. These are names for gels, usually describing the color of the gel.</p>