Friday, July 4, 2014

Dealing with noise in night photos without a tripod

Taking photographs at night is not usually a problem when you can use a tripod and simply extend the exposure time to lower the ISO. On this occasion I was on a moving ship where using a tripod was not an option. I had to try to balance a shutter speed sufficient to stop the action with an ISO that was not going to over-dramatize the noise level.

The first thing to do is to switch to a fast aperture lens.  Moving from an f/2.8 lens to an f/1.4 lens is the equivalent of dropping from ISO 6400 to ISO 1600 --  a very significant jump.

The second thing I do is do is put the camera in continuous shooting mode.  When you hit the shutter the first time the motion moves the camera and adds to the blur. With a burst of several shots at least you have a period when the camera will be steady enough not to cause undo blur. Of course a lens with vibration reduction is also quite helpful.

The photos below were all taken at night. The best circumstances gave me an ISO of 1600 on the Fuji X-T1,  while for the worst situation I had to use an ISO of 3200 on a Leica M. Night shots like these result in very large dark areas where noise builds up the most. Fortunately, these areas are in the clouds where there is little detail. This enables me to treat those large areas differently than sections of the photo where this is considerable detail.  All the images are processed as RAW and brought in as 16-bit to make things easier in post-processing.

I apply noise reduction in Adobe Camera Raw, bringing in each image twice. On one version I apply moderate noise reduction so as not to destroy the areas of detail. This works well because noise is not as apparent in areas with considerable detail  On the other version I apply much more noise reduction to deal with the large areas, such as clouds, where there is considerable darkness and not detail. Later in Photoshop I place one layer over the other and paint out the details where I want them, leaving the large areas noise-free.  

This photo and the one below of cargo vessels passing at night I kept detail in the ships and sea while reducing the noise considerably in the sky. The camera was a Fuji X-T1 with 14mm f/2.8 Fuji lens. This gave me an ISO of 1600 and shutter speed of 1/20th of a second in the top image and 1/12th second for the bottom one. I also had to open up the right side of the second photo, which resulted in even more noise.  Lightening a dark area later in post-processing has the effect of adding noise equivalent to increasing the ISO.

This photo was taken late at night while passing the Rock of Gibraltar. It was taken with a Leica M (240) and 35mm f/1.4 lens at ISO 3200 and shutter speed of 1/15th of a second. Leica lenses do not have vibration control making it necessary to steady the camera as much  as possible. The only place with detail was in the rock itself so I kept the noise reduction low for that area only. 

1 comment :

  1. Nice, thanks… the fuji 14 2.8 does not have vibration control either. (you mention leica not having it.) Looking forward to your conclusions after the trip.