Help with taking Santa pictures

I'm going to be taking Santa pictures for free at our local library. I'm a hobbist, so any professional advice would be great. The location is in the children's library located in a basement like area with low ceilings (poor fluorescent lighting). I have a Canon 6D, 35mm F2 IS and 85mm F1.8. Which lens should I use in this situation? What would be the best lighting setup. I have 3 speedlites, one umbrella and one 24x24 softbox.

are you planning on using your own backdrop or relying on the ambient?

if you are using your own backdrop, the fluorescent wont be an issue and the whole things gets easy. if not you should gel the speedlights green, shoot raw and fix the w/b in post by shoot a grey card while on location, make sure to set a shutter speed at a multiple of 60, to match the phase cycle of the lights and get consistent lighting

as for a light setup, i'd use the softbox as my key light, the umbrella at half power of the key for fill and use the third light behind at 1/8 or 1/4 and up high and out of the frame for some rim lighting if you want.

as far as lens type, the 85 would be my choice but it might be tight if you want to grab a entire scene, use the 35 if space is an issue but watch distortion with objects at the end of the frame.

I'd stop down to f8 or so and then raise your ISO as required to help out the speedlights if they arent providing enough power..

another lighting option dealing with the ambient if is to use the two lights to evenly light the background (you will need another umbrella) and use the softbox and get a white or silver reflector for the fill of the subjects.

As mentioned above so much depends on your background and the ambient light. For the key light its often best in these photos booth situations to use a single flash above the camera in your largest modifier, in this case an umbrella. The goal here isn't custom portrait lighting but rather the ability to accommodate a lot of variation as Santa and kids move and wiggle around.

Lighting the background is important. If you are shooting in a dark room with a distant background kids with dark hair will lose the top of their hair in the shadows. So you may need to use one or two of your speedlite to either serve as a background or rim light. Background lights are aimed at the background to brighten it up. Rim lights are aimed at the back of the subject, usually off to the side or above to break up the subjects edge from the shadows.

The children librarians are making a backdrop. Not sure what will be on it, but I thing it is going to be mainly white.

Making white look white means lighting it.

brian4646 wrote in post #17807014
I'm going to be taking Santa pictures for free at our local library . . .

You are either a hero or willing to play one for Christmas. I suspect your most important setup will be personal supplies of patience, tolerance and joy.

In particular I think it would be useful to ignore the long line that may appear and take your time with each family.

I was on the receiving end of this for a decade or so as a department store Santa. My photographer was a professional fashion photographer who did this as a favor to the store's fashion department. He used a single strobe in a relatively small reflective umbrella. We had a sleigh with a decorated flat behind. He balanced with the ambient and his shots always looked nice and "poppy" -- and since it was an old school film camera with a Polaroid back, he had to get it right consistently!