Friday, 11 May 2018

Canon EOS M100 evaluation of low light performance

One area of particular technical superiority of large sensor cameras (DSLRs and MILCs) is that they have a large lens which lets more light in, the result is much better low light performance than compact cameras. With this in mind I set about evaluating the low-light performance of the EOS M100 using trains as subjects. All the photos were taken at Main South Line Bridge 7 at Opawa.

There are a few tricks to be aware of when taking photos in low light conditions. Such as:
  • Do you need a tripod to hold the camera steady?
  • Ensure you select manual exposure to balance the shutter speed and aperture and to reduce the amount of processing the camera has to do.
  • Ensure you select manual focus and prefocus the lens on the target. This is particularly important since many cameras will have difficulty autofocusing in low light.
  • You need to consider what you expect from a photo taken under low light. If the target is moving it is likely to be blurred in low light conditions.
The EOS M100 can go to ISO 25,600 which is two stops better than the EOS 600D that I also have which has a maximum ISO setting of 6400. In this case I set the maximum ISO for the camera to use on auto ISO to 6400 for the first tests and 12,800 for the rest. When shooting video the EOS M100 can only shoot at up to ISO 6400 maximum.

The camera is normally set on AF+MF setting, where if the autofocus fails to work you can just turn the focus ring to set it manually and it automatically magnifies the centre of the picture. The problem with this is the focus will only hold as long as you keep the shutter button half depressed. I had two occasions where the manually set focus was lost and the camera refused to release the shutter. When I set the camera to MF I was able to set and leave the focus without having to hold the shutter halfway.

The one video I shot came out jerky and I will need to do more work to discover the reasons for this, such as camera settings or issues specific to low light.

A selection of still shots is below: