Talking about the sensors of Nikon D5100 and Canon Rebel T3i, the second has a higher sensor resolution with 18 Mega Pixel compared to 16.2 Mega Pixel. The most common belief is that the higher the resolution is the better the device is. Therefore, with this comparison, canon Rebel T3i got the advantage.
Because Canon Rebel T3i got a higher sensor resolution, to be able to fit the 22.3×14.9 millimeter 18 Mega Pixels sensor to Canon Rebel T3i, which is not as big as the 23.6×15.6 millimeter DX format sensor which is found in Nikon D1100, the pixels of Canon Rebel T3i were packed together closer and is made smaller. The size of the pixel of Canon Rebel T3i is smaller compared to Nikon D5100. Nikon D5100’s pixel pitch is 4.78 µm and Canon Rebel T3i’s pixel pitch is 4.3 µm.
The sensor’s number of pixels and the sensor’s imaging area are divided to be able to get the pixel density or how close the location of the pixels. Nikon D5100 has a lower density compared to Canon Rebel T3i. The latter has 5.4 Mega Pixels / cm² of pixel density and Nikon D5100 has 4.4 Mega Pixels / cm² of pixel density. Having a higher pixel density doesn’t mean that it has all the advantage. It also has lots of disadvantages. The disadvantage of having a higher pixel density includes the reduction of ISO performance, a higher possibility of having camera shake, the lowering of the dynamic range, and some issues on diffraction.
A sensor test was conducted where it compares the result of having a higher pixel density and lower pixel density. DxOmark Laboratory, an independent Laboratory have supported the argument that having a higher pixel density has many disadvantages. It informs that lower pixel density has better output of RAW sensors therefore, Nikon D5100 has better output of RAW sensors compared to Canon Rebel T3i. Output includes a high capability of ISO, a good dynamic range and a better colour depth.
A Camera having a higher resolution sensor must go with a lens where it provides essential resolving power needed in capturing the minute scene details. To be able to get the best result of the high resolution sensors, it is needed to have high end and more expensive lenses.
Below are the findings on how appropriate to its respective cameras are the 18-55 millimeter zoom kit lenses of Nikon and Canon.
When compared to which offers the best ISO performance and boost, Nikon D5100 have the highest votes. Nikon D5100 has up to 25,600 ISO and it also offers a better and higher ISO performance. The ISO boost settings of Nikon D5100 is from 6400 ISO up to 1/3 stop increments while Canon Rebel T3i is from 6400 ISO up to 12,800 ISO.
The two cameras have Auto ISO. This verifies the best fit ISO setting.
Auto Sensitivity ISO Control feature is also offered by Nikon D5100. This feature will be activated in the shooting menu of the camera. ISO sensitivity can be adjusted by turning it ON and OFF. When turned ON, it automatically adjust the ISO sensitivity if the ISO setting did not achieve the optimal exposure set. There is also an option for adjusting the shutter speed. It can be turned to minimum or maximum speed. Turning the shutter speed into the minimum speed may increase the ISO sensitivity only if the minimum speed is not attained by the ISO setting.




