How to light spontaneous portraits?

Question

I currently am in Singapore for an exchange year. The architecture here is impressive, the lights at night are wonderful, but what I find to be the most interesting are the people. You can find people from all races, sizes and ages here.

I would love to just ask some of them on the street, in the bus, in the MRT stations or in the malls if I could take a photo of them. However, I guess, a little preparation can't hurt as I'm not too experienced with portrait photography - especially with the lighting.

Can you give me some tips on how to light spontaneous portraits? This means I can't put up a studio environment and don't have much time to adjust the lights. Furthermore, I'll have to deal with an array of different lighting situations (outside, sunny, cloudy, at night, in a mall, etc). Last but not least, I don't want to scare people away with huge amounts of equipment!
Should I buy a flash, and if yes, which one?

Of course other tips on both interaction with people and the technical side are welcome, too.

PS: My equipment is a Canon EOS 450D + EF-s 60mm / f2.8

PPS: Thanks to everyone for your tips! Here is one of my first shots:

Answer 1

You light spontaneous portraits with available light. Sure, flashes, strobes, kinoflos, etc are great tools and really expand your visual vocabulary, but at the end of the day, nothing is as authentic and versatile as available light.

Start observing light. Find a cool light source - be it a back lit outdoor ad, a store display, etc. Look at how it lights people. Go with a friend, ask them to move around the light as you watch them. See how the light breaks, how it changes their features. Have a couple go-to moves - a direct ceiling light from above, a shot incorporating street lights, maybe a shot in the shade with a blue sky in the background, the specifics don't matter. Just don't stop experimenting, there's so much awesome mixed light in most city environments, it's a shame to overpower it with strobes just because that's the easy out.

If you absolutely must buy gear, get a Speedlite - a 580, 430, doesn't matter - and a cable. Being able to remove the light from the camera and movie it around your model is absolutely crucial. Learn to control ambient via shutter speed and flash exposure via aperture, there's a lot of great info on doing that on strobist.

And remember, there really are no correct answers, photography - especially non commercial photography - is all about expressing your vision. Have fun with it!

Answer 2

I'm not a street photographer, but I imagine that for this kind of photography you are pretty limited to an on-camera external flash, if at all. So I'd more rely on a lens with a big aperture. The EF 50mm f/1.8 II of EF 50mm f/1.4 USM for example.

Personally, I'd prefer one of the good zooms (you did not mention your brand, I assume Canon), EF24-70mm f/2.8L USM seems like a good (pricy) choice, but keep in mind that it is relatively big, and may be intimidating in some situations. A lighter alternative for crop-sensor would be the EF-S 17-55 f/2.8 IS USM

As for choice of a flash - the Canon Speedlite 580EX II is a great unit with lots of power on customizability, and can serve as a master or a slave (if you have a EOS 7D, that's all you need). But, it is BIG. I guess though, that for street snapshots the lower priced and smaller footprint Speedlite 430EX II is just fine.

Since you are not looking for shooting in a controlled (studio) environment, one of the aftermarket, TTL compatible flashes will do just fine for less $$.

Answer 3

I happened to just do a session like this... except that it was at night and in constant motion (as was I). Much of it was outside (in a downtown setting) or in dark rooms. As such, using only natural light wasn't really an option; everything would have been too dark/blurry.

I ended up going with an on-camera flash (SB-600) in TTL mode with a Sto-Fen OnniBounce. At an angle, it gave me a relatively diffuse lighting, and it bounced a bit when indoors. (Most of the ceilings were high so this effect was limited).

I still attempted to use as much natural light as possible: * I boosted ISO * I opened up my aperture fairly wide (f/2.8) in aperture priority mode * For the outdoor shots, I tried to wait until I had good lighting from street lights etc.

Overall, the light wasn't bad. It was pretty much all on-axis (which was less than ideal) but it served its purpose. TTL and aperture priority mode ensured that I got a correct exposure without fiddling with my controls too much.

I also had a somewhat wide lens (35mm/52mm EFL), which meant I was relatively close to my subjects. In turn, I was then further away from the background, which kept it from being lit by the flash. The resulting backgrounds were nice and dark, providing good separation for my subject.

The real boost came in post-production editing though. I had to tweak each photo to even out the lighting. (Lightroom's Graduated Filter and Adjustment Brush came in very handy.)