Looking to gel a flash, but what color?

<p>I've got a 430EX II and a Rosco swatchbook, so I ought to be set. I can use a gray card to set the camera to the ambient light. But alas, there doesn't seem to be any way to beat the white point information out of the camera. This is unfortunate - it would be nice to be able to use the camera as a color meter.</p>

<p>Is there any way to make the camera tell me the temperature? I'm working with a 5D mk 1 and a 30D. If I can't find out for sure, is there any way other than trial and error to find a good gel?</p>

<p>Thanks for any tips!</p>

 

<p>You don't need to be exact when gelling a flash; you just need to get close. I mean, besides knowing that you need a full CTO or CTS to correct for tungsten and a full Plusgreen to correct for fluorescent, there's not much else you need to memorize.</p>

Also ask yourself if you want to match your gels completely to the ambient. With tungsten, it's sometimes nice to gel a half-CTO, and WB for that, giving your subject natural colours, while leaving the background slightly reddish, to give that `inside-cosy' look.

 

Don't forget to bring some blue for those shady/cloudy outdoor fill-flash shots...

<p>Here's some information you might find useful as to which gel to pick. All of these come in the standard Rosco gel swatchbook.<br>

http://www.rosco.com/us/filters/cinegel.asp</p>

 

<p>Or just set custom WB for the naked flash + ambient light combination if the ambient light is not overpowered by the flash: if the flash totally obliterates the ambient spectrum, use flash WB. If you want to be really anal about it, get a color checker card and run a series of tests with blue-ish and salmon-ish colored gels on the flash head viewing the results on a calibrated monitor (if this is your first time with a color checker card read the instructions which squares should be viewed in pairs and why...) One caveat though: unless your ambient light sources are stable (i.e. the spectrum doesn't fluctuate) forget about gels and just use custom WB.</p>

<p>I would agree with Michael. I think you can make all your adjustments using different white balance setting I.E. cloudy, sunny or custom. If I rember correctly the 430 is a fully automatic flash and is really dependent upon its ettl readings. By placing a gel on this flash without being able to set the flash manually I think you will create an exposure issue. Set correctly the Canon flashes while not as good as Nikons do ok but can be unpredictable. I wouldn't complicte this more with Gel. However, on studio strobes where you have a lot more power and control gels are a nice addition.</p>

<p>I eyeballed a color by (1) setting the camera to flash white balance, and (2) shooting a gray card without the flash. That gave me a color. I then (3) looked through the gels and found one that roughly matched. Taped it over the flash and it appears to be working as expected; mixed flash/ambient look much better than mixes without the gel. I tried 3/4 CTO and full CTS, both against a low-watt bulb - they worked similarly.</p>

<p>It's difficult to tune it to a specific situation, because I don't have a specific situation in mind at this point. I'm only wanting to get some experience with this before I need it on a real shoot.</p>

<p>The 430EX II is an E-TTL flash, but I'm not sure why that would mean it has trouble with gels. E-TTL does use focus distance information for setting the approximate flash power, but it's fine-tuned with the actual light coming through the lens. Or so I understand it, anyway.</p>

<p>Thanks for the tips!</p>