Dealing with bad light

Toni Lamprecht in one of his current projects
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We had a fantastic day of climbing in Kochel last friday. Toni worked on a new project and I had the chance to jumar along to take pictures. Unfortunately, the weather wasn't great and light was absolutely terrible. Still, I wanted to get a couple of nice shots, so I kept playing with my camera's settings trying to get a grip on the situation.



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Note: I'm not a wizard at this. In this post I try to explain the things I figured out while shooting/jumaring and looking at the results afterwards, so everything you read here should be taken with a little caution. I'd love to hear your suggestions, so please feel free to write me via email or in the comments, especially if you've got ideas how I could have improved things!

Hanging from a fixed rope I didn't have a free hand to work an off-camera flash, so I was stuck with either blasting away with on-camera flash or with shooting high ISOs around 3,200. While the D90 is pretty good at working high ISOs (even 3,200 is still usable) the images still suffer much because colours and contrasts become so crappy in bad light such as this. (Have a look at the image on the left; Note: I accidentally poured too much noise reduction into it during post-processing, the D90 actually handles noise better than this, I was just too lazy to reprocess the shot)

The other option, on-camera flash, isn't great either. Letting the camera take control, you get a subject blasted in white, harsh light with everything else turning into total blackness. Nice if you're doing a portrait session at the Draculas', but not that great for making vibrant images of climbing on God's green earth...

The shot to the right is what you get if you leave dealing with bad light to the camera...

But if you have to use on-camera flash, there are a still few things you can do do make it look better than what your camera's auto settings will deliver.

Set your camera-flash sync to rear curtain sync

This way your camera first gathers some of the ambient light (how much it gathers depends on the shutter speed you choose) before freezing your subject with your flash as it fires at the end of the exposure. I prefer to shoot in Shutter priority mode for this, meaning I set the shutter speed as fast or slow as I want and let the camera choose a fitting aperture. (I don't often go into full manual mode because when I'm hanging from a rope and things are moving fast I like to leave as much work to the camera as possible) You can also shoot in program automatic mode, but in dark conditions the camera often chooses crazy long exposures up to a couple of seconds. This is because the camera tries to fully expose the image with the ambient light instead of just gathering a little bit.
Choosing the correct shutterspeed is always a trade off. The slower the shutter speed, the more (good) ambient light will be gathered and your flash will have to blast less (bad) artificial light into the image. The downside is that with longer shutterspeeds anything that moves will be increasingly blurry and it often comes down to luck whether the image is still usable or not. (It looks good when a moving hand is blurred but the climber's face usually should be sharp) I like to use 1/30th as a starting point and go from there. At 1/30th your chances of getting sharp images with a little but not too much blur are pretty good and it is long enough to allow some ambient light to seep in. (The images above were shot at 1/20th in order to collect more ambient light)

More on rear-curtain sync can be found here

One way to gather more light at the same shutterspeed is to boost your ISO. If you're working with auto ISO (which I do quite often) while using flash, the camera prefers to increase flash power instead of boosting ISO. (That's the case with the Nikon D90, your camera or brand might be different) If your camera does that, you might want to set your ISO to manual and choose a higher value, something between 400 and 800 might be fine. I have to admit I forgot to do that with these shots. I guess I should have boosted the ISO (auto ISO chose 320) instead of lowering the shutterspeed down to 1/20th. Lucked out, though, so no harm done...

In the end, it is all about balancing the different light sources. Especially when using "ugly" flashed light (meaning on-camera) you'll probably want to balance it with the ambient light in such a way that you don't really notice the flash. It's like adding make-up. Improve the look but make it look as if you hadn't.

Again, I'm not a wizard at this. As I said before, I'm still fairly inexperienced and almost every day I learn something new about taking better images. Look at this as an attempt to make my own learning progress as transparent as possible by laying open my own "source code". I hope you find something worth your while here!

Cheers
Bruno