Canon T4i High ISO NR
Canon T4i Noise Reduction
The Canon Rebel T4i's four High ISO Noise Reduction settings provide good flexibility in choosing how you want to make the trade-off between subject detail and noise levels. Crops from the new Multi-Shot Noise Reduction feature which blends four images captured in a burst together to average out noise are also included.
The Canon Rebel T4i applies noise reduction to its JPEGs at all ISOs, so we've included crops at all ISOs in the table below.
To our eyes, the default "Standard" level of noise reduction strikes a good balance between noise and subtle subject detail, although the red fabric swatch presents a real challenge at higher ISOs, as it does for many cameras we test. Cranking the noise reduction setting up to "Strong" produces very smooth-looking images, while still maintaining good detail in areas of high local contrast (as seen in the circular scale), but a lot of detail is lost in areas of subtle contrast (the red fabric swatch is a particularly challenging subject, and the detail loss there is worse than you'd find in most real-world examples). At the other end of the scale, the "Disable" noise reduction setting (which obviously doesn't disable all noise reduction) leaves more noise in the image, but also leaves a lot more subject detail: Use this setting if you have good third-party noise reduction software; with appropriate processing, the result could be quite good. You should be able to do even better working from the raw files. The new Multi-Shot Noise Reduction feature does result in lower noise with better detail retention than conventional noise reduction, but it still smears detail in the red fabric swatch a little more than we'd like.