ISO Sensitivity / Noise levels

ISO equivalence on a digital camera is the ability to increase the sensitivity of the sensor. This works by turning up the "volume" (gain) on the sensor's signal amplifiers (remember the sensor is an analogue device). By amplifying the signal you also amplify the noise which becomes more visible at higher ISO's. Many modern cameras also employ noise reduction and / or sharpness reduction at higher sensitivities.


To measure noise levels we take a sequence of images of a GretagMacBeth ColorChecker chart (controlled artificial daylight lighting). The exposure is matched to the ISO (ie. ISO 200, 1/200 sec for consistency of exposure between cameras). The image sequence is run through our own proprietary noise measurement tool (version 1.5 in this review). Click here for more information. (Note that noise values indicated on the graphs here can not be compared to those in other reviews.)

Panasonic DMC-LX3 vs Canon Powershot G10 vs Nikon Coolpix P6000
(ISO 64-3200)

Panasonic DMC-LX3
ISO 80		 Canon Powershot G10
ISO 80 		Nikon Coolpix P6000
ISO 64

Panasonic DMC-LX3
ISO 100 		Canon Powershot G10
ISO 100 		Nikon Coolpix P6000
ISO 100

Panasonic DMC-LX3
ISO 200 		Canon Powershot G10
ISO 200 		Nikon Coolpix P6000
ISO 200

Panasonic DMC-LX3
ISO 400 		Canon Powershot G10
ISO 400 		Nikon Coolpix P6000
ISO 400

Panasonic DMC-LX3
ISO 800 		Canon Powershot G10
ISO 800 		Nikon Coolpix P6000
ISO 800

Panasonic DMC-LX3
ISO 1600 		Canon Powershot G10
ISO 1600 		Nikon Coolpix P6000
ISO 1600

Panasonic DMC-LX3
ISO 3200 		Canon Powershot G10
n/a		 Nikon Coolpix P6000
ISO 2000

This is quite an improvement over the LX2, with the LX3 generally doing a good job of balancing noise and noise reduction. Noise is not particularly prominent until ISO 800 from which point it becomes increasingly apparent. Unlike its rivals, it is still able to reproduce fine detail roughly as well at ISO 400 as it can at ISO 80, while the others are starting to blur it away with increasing noise reduction. The LX3 is still pretty good at ISO 800, despite noise becoming more obvious and again, good levels of detail are retained. ISO 1600 is not so impressive and ISO 3200 is as poor as you might expect.

The graphs below suggest that the LX3 is producing least noise of the three cameras, despite the above crops suggesting it's applying the least drastic noise reduction.

(The ISO 2000 images for the P6000 are included as this is the highest sensitivity setting at which it creates full-resolution output)

Luminance noise graph

Cameras compared:
Panasonic DMC-LX3, Canon PowerShot G10, Nikon Coolpix P6000

Indicated ISO sensitivity is on the horizontal axis of this graph, standard deviation of each of the red, green and blue channels is on the vertical axis.

Chroma noise graph

Indicated ISO sensitivity is on the horizontal axis of this graph, standard deviation of each of the red, green and blue channels is on the vertical axis.