gotdesign01 Posted January 30, 2008 Share Posted January 30, 2008 In a couple weeks I will be taking some portraits of a family gathering that will take place in a hall with mercury vapor lighting. Does anyone know a good custom WB setting on a EOS 10D for use with MV lights? Please e-mail me at GotDesign01@gmail.com Thanks much. Link to comment Share on other sites More sharing options...
bobatkins Posted January 30, 2008 Share Posted January 30, 2008 Custom white balance taken off a white or grey card is always the most accurate method for shooting JPEGs Mercury lights don't have a continous spectrum and can't easily be assigned a color temperature. Modern designs have a phosphor coated envelope which can help, though they still tend to be biased towards the blue. I'd shoot RAW (or RAW+JPEG) and work on the correction in RAW post exposure processing. Link to comment Share on other sites More sharing options...
lester_wareham Posted January 30, 2008 Share Posted January 30, 2008 Like Bob said, I assume they will change WB with the mains frequency like other fluorescent lights, so a tripod and shutter speed of 1/50 or 1/60 (whatever your mains frequency is) might be advised. Link to comment Share on other sites More sharing options...
m_barbu1 Posted January 30, 2008 Share Posted January 30, 2008 Also, if you want E-mail notification, I believe there's a link you can click at the bottom of this thread. Link to comment Share on other sites More sharing options...
mark u Posted January 30, 2008 Share Posted January 30, 2008 The other tactic is to drown out the mercury lights with flash. That's probably reasonably easy to achieve for individuals and couples, but requires a lot of light once you get up to groups and tables. You will want to avoid mixed lighting. If at all possible try to get into the venue and run some tests ahead of time. If you have a good selection of flash gels you may be able to supplement the venue lighting with flash that has been gelled to give a reasonable match, but it could be tricky. These spectra give you an idea as to why: http://ioannis.virtualcomposer2000.com/spectroscope/amici.html#1p Link to comment Share on other sites More sharing options...
emmett_ward Posted January 30, 2008 Share Posted January 30, 2008 Either use a gray card to custom your white balance, or if possible get your hands on an Expo Disk. I do a lot of shooting in school gyms, and it is a lifesaver. Link to comment Share on other sites More sharing options...
alan_myers Posted January 30, 2008 Share Posted January 30, 2008 Hi Aaron, Definitely set a custom white balance. Don't try using straight flash as a FILL along with the mercury vapor ambient lighting. The flash will not match the custom white balance you've set, and you'll get strangely mixed light as a result. It's impossible to set a custom white balance for ambient + fill flash, since the ratio of one to the other will change with every different shot. Instead, if you need to bounce extra light onto your subjects or to open up shadows, try one or two silver (neutral) reflectors. That way any fill light you use is the same color as the main lighting from above. Or use FULL flash, as suggested by Mark. Alternative would be to gel your flash. Gels can be used this way to adjust your flash's fill output to closely match ambient light. But it's tricky to do with mercury vapor because they vary in color bulb to bulb and there are a couple different approaches to color correction. In the past I've used 60 to 80 Magenta gel combined with a 15 to 20 Cyan gel or just used a 50 to 60 Red gel. Again, the exact gel needed varies under differing mercury vapor light, so you'd have to experiment a little in advance, take some test shots to see what actually works best in the particular situation where you are shooting. Also make a few reference shots early on, with a white or gray prominent card in them. Later you can use that target in Photoshop (or whatever), to get finer color correction. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now