My wife Aoife sings in a choir based in Drumcondra called Dolce, and last night was their annual christmas concert. It took place in the church in St. Patrick’s College and they were looking to have a few photos taken during the concert, with a group shot at the end of their rehearsal before the doors opened to the general public. For the shots during the concert it wouldn’t be possible to use flash, but for the group shot I was going to have about 20 minutes to prepare and decided to attempt in that time to set up strobes to illuminate the group for a nice evenly-lit shot.
I could have attempted an ambient-light group shot, but I would have been at an ISO of close to 2000, at f/2.8, and still pushing the limits of shutter speed. Essentially, I was not confident that I would have come away with a sharp, or even usable, group photo. And it wouldn’t have been as much fun!
My hope was to use the 20 minutes I had (it ended up more like 15 minutes) to set up three lights – two to cross light the group from front and back, and the third to fill in the shadows. I was more inclined to pursue this option having recently read a fantastic primer on how to shoot a large group in a big dark space courtesy of David Hobby at Strobist, where he detailed exactly what I needed to do. In that case he was talking about a gym, with elevated bleachers from which to light – here I was going to be in a church, but I had 8 foot light stands which would hopefully be close enough.
What follows here is exactly what he describes, and he explains it better than I probably can, so I suggest you look at his post for a deeper understanding of the setup after you’ve read this one.
Having decided to light the shot artificially the first step is to figure out a shutter speed/aperture/ISO combination that works. Shutter speed is easy – I want to kill most or all of the ambient, so I put it to 1/250s, which is the fastest my Nikon can shoot at when using flash. I need to light a large group evenly, so the lights need to be put quite a distance back. Accordingly I need to be kind to them when choosing an aperture and ISO. If I close down the aperture and stick at ISO 200, I’ll need more power from the flashes than they can provide. A wider aperture allows more of the flash light to hit the sensor; a larger ISO amplifies the light that does hit the sensor even more; use both and you’re into what David calls “flash-friendly” exposure territory, where less power has more impact.
I first went to ISO 800 (as I’m ok with ISOs up to that on the D300) and f/5.6 (wide enough to be flash friendly, but still hopefully giving me some depth of field to keep the group in focus). Once I got my lights set up later I opened it slightly to f/5, but it was close enough to start with. That set, it’s time for an ambient-only shot to see that I’ve killed off most of that light. As you can see from the top right shot, that was successful.
Now I add in my main light. This is going to be at camera left, high and bare, and ideally at 45 degrees or so to the group. In fact it’s more like 30 degrees due to pillars in the church that would otherwise cast shadows on the group. The main thing to watch here is that it evenly lights across the group. If I point it at the centre of the group it will light the people nearer the flash more than those further away, so I point it towards the right hand side, and the light spills more evenly. Similarly I aim it slightly above the group so that the front row doesn’t get more light than the back row. A few tests later, adjusting the light position, and I have the look you see on the right. I’m at half power on the flash, with it zoomed to 70 degrees, and it’s giving me something that looks good on the back of the camera.
Notice how the wall at the right has light falling on it, but not at the left – that is due to the light being feathered across the group as I described. Notice also how all the people in the group are reasonably evenly lit. There’s still lots to improve here, but if Deirdre, the choir’s conductor, turned around now and asked me for a shot then I could use this one-light setup and probably get something that (with some post-processing) would be usable.
But I still have time, so lets set up my second light. This is going to do two things – it is going to add some separation between the group and the dark background, and it is going to illuminate the wall at the left hand side of the frame. I position it behind the choir, just barely out of frame at camera right. It’s firing across the backs of the back row of the choir and is also zoomed to 70 degrees and at half power. Keeping this light out of the frame causes me some difficulties and I spend more time adjusting the position of the stand to try to achieve that than I do adjusting it’s power or zoom.
The shot on the right isn’t a test shot, but one of the four shots I took when the group were in position and posing for the camera, but here my third light didn’t fire as I was blocking the infra-red receiver on it, and so you can see how my main and back lights are working together. This is an improvement over the single light option, and the back wall is nicely lit on both sides now. Also many of the choir members have a nice highlight from the back light – if I could have raised it higher possibly all of them could have this (which is I guess where bleachers in a gym come in useful).
So all that remains is for me to use my third flash to provide some fill light, and lift the darkness in the shadows cast by the other two lights. It will also illuminate the central part of the wall behind the choir, and has the added bonus of being something I can get the choir to make sure they can see. I have it in my left hand, which crosses under my right hand in which I hold the camera, so that the light is just barely at camera right. This tweak (I’d naturally have held it at camera left) is straight from David Hobby’s “how-to” post, and helps to avoid double shadows as it is at the other side to my main light, the source of most shadow.
Incidentally I triggered all the lights using Nikon’s wireless CLS system with the pop-up flash as commander, and the fill light ended up at 1/4 power
So fifteen minutes preparation, four final frames, three of which have all three lights firing, some nice posing by the choir, with little direction from me except to bunch together slightly, and what I think is quite a nice shot of 69 people in a dark church on a December’s evening. I like the shot that keeps the environment in the frame, but an alternative crop is below.
If I had five more minutes, I would have thrown a fourth light on the floor behind the choir pointing straight up to illuminate the top of the frame, and I would have investigated if it was possible to move the piano. In fact the piano is the only thing that bothers me about the shot, but it was needed for the concert that was about to start, and it’s not something that is very easily moved, so it had to stay put.