Canon T7i has a
24.0MP APS-C (22.3 x 14.9 mm ) sized CMOS sensor and features DIGIC 7 processor. On the other hand, Canon 500D has a
15.0MP APS-C (22.3 x 14.9 mm ) sized CMOS sensor and features Digic 4 processor.
Canon T7i's sensor provides 9MP more than Canon 500D's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the T7i and 500D sensor size comparison.
Sensor Size and Resolution Comparison image of Canon T7i and Canon 500D Cameras
Canon T7i and Canon 500D have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Canon 500D has 59% larger pixel area (22.08µm 2 vs 13.84µm 2 ) compared to Canon T7i, it has larger pixel area to collect light hence potential to have less noise in low light / High ISO images.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Canon T7i
or the
Canon 500D ,
including hyperfocal distance.
