Low Light: Know your limits

Low Light: Know your limits

Shooting low light is not about squeezing every last 1/3 ev out of every exposure parameter. It is about knowing the usable limit of each parameter and using that.

  • ISO: The XT-1 has a great detail at ISO 1600, so I fix at that in low light.
  • Exposure Length: Minimum for each lens, for example XF10-24 can produce a sharp shot at 1/2s, given a static subject. XF56 requires 1/180th, XF23 is fine at 1/125 as is 50-140. See also [Mildly Explicit] Damien Lovegrove’s article on the XF50-140 vs XF90, it contains a useful table of minimum shutter speeds for fuji lenses.
  • Aperture: Also varies with each lens, and wide open is not always the answer. Some low light situations are very contrasty (events, gigs etc) and also back lit, this situation will bring out the flaws in most lenses, and this will be most pronounced wide open. If the artefacts are too much, close it down a stop or two.

The result of limiting, your ISO, exposure length and aperture will probably be an underexposed shot, but that’s fine, push it back up in LR or your raw processor of choice.

RAW files give enough latitude and shadow detail, that it really can be worth stopping down even though the available light suggests shooting wide open. The important thing is to know ahead of time how far you can push each parameter. A sharp shot thats 2 or 3 stops under will be much more useable than a soft/blurred/overly noisy shot.

There is also a feature request here… The XT-1 allows you to configure a maximum exposure time and maximum ISO for auto ISO mode, great, it won’t bump up the ISO until the maximum exposure time is too short. However once the maximum ISO is reached, exposure time will be increased beyond the configured maximum if metering demands it. I would like the option to not go longer than the configured max exposure time and if the frame is under exposed, so be it.