Pentax 645D vs Sony A7R III

Here is a complete analysis of the Pentax 645D vs Sony A7R III, former being a Pro DSLR while the latter is a Pro Mirrorless by competitors Pentax and Sony. The sensor resolution of the 645D (40MP) and the A7R III (42MP) is pretty close but the 645D (Medium format) and A7R III (Full frame) use different sensor size.

Photography Glossary

The 645D was launched 8 years earlier than the A7R III and that is a fairly sizable difference as far as camera technology is concerned. Both the cameras come with different body type with the Pentax 645D being a Large SLR camera and the Sony A7R III being a SLR-style mirrorless camera.

Before getting in to a more detailed comparison, below is a simple introduction of how the 645D grades vs the A7R III for portability, imaging, features and an overall rating.

Following is a preview of the gallery images for Pentax 645D & Sony Alpha A7R III. The complete galleries are viewable at Pentax 645D Gallery & Sony A7R III Gallery.

For anyone who is aiming to carry your camera, you will need to take into account its weight and size. The Pentax 645D comes with physical dimensions of 156mm x 117mm x 119mm (6.1" x 4.6" x 4.7") and a weight of 1480 grams (3.26 lbs) while the Sony A7R III has specifications of 127mm x 96mm x 74mm (5.0" x 3.8" x 2.9") having a weight of 657 grams (1.45 lbs).

See the Pentax 645D vs Sony A7R III in our completely new Camera plus Lens Size Comparison Tool.

Always remember, the weight of an ILC will vary depending on the lens you are utilising at that moment. Following is the front view sizing comparison of the 645D against the A7R III.

Taking into account dimensions and weight, the portability score of the 645D and A7R III is 50 and 63 respectively.

Typically, it is difficult to picture the gap in sensor sizing simply by looking through specs. The visual underneath will help offer you a greater sense of the sensor dimensions in the 645D and A7R III.

As you can plainly see, both of these cameras posses different megapixel count and different sensor sizing. The 645D due to its bigger sensor is going to make shooting shallower DOF less difficult and the Sony A7R III will provide you with greater detail utilizing its extra 2MP. Higher resolution will also make it easier to crop photographs somewhat more aggressively. The older 645D will be disadvantaged with regard to sensor innovation.