Olympus E-P3 vs Pentax K-S1

Its time to look a bit more in depth at the Olympus E-P3 and Pentax K-S1, former is a Entry-Level Mirrorless while the latter is a Advanced DSLR by companies Olympus and Pentax. There is a noticeable difference among the resolutions of the E-P3 (12MP) and K-S1 (20MP) and the E-P3 (Four Thirds) and K-S1 (APS-C) possess totally different sensor sizes.

Photography Glossary

The E-P3 was released 4 years prior to the K-S1 which is a fairly sizable difference as far as camera tech is concerned. Each of the cameras come with different body type with the Olympus E-P3 being a Rangefinder-style mirrorless camera and the Pentax K-S1 being a Mid-size SLR camera.

Before we go through a more detailed comparison, below is a simple synopsis of how the E-P3 scores vs the K-S1 when it comes to portability, imaging, features and an overall mark.

Following is a preview of the gallery images for Olympus PEN E-P3 & Pentax K-S1. The complete galleries are available at Olympus E-P3 Gallery & Pentax K-S1 Gallery.

If you're going to travel with your camera frequently, you should take into account its weight and proportions. The Olympus E-P3 enjoys outside measurements of 122mm x 69mm x 34mm (4.8" x 2.7" x 1.3") accompanied by a weight of 369 grams (0.81 lbs) whilst the Pentax K-S1 has measurements of 121mm x 93mm x 70mm (4.8" x 3.7" x 2.8") and a weight of 558 grams (1.23 lbs).

Contrast the Olympus E-P3 and Pentax K-S1 in our completely new Camera & Lens Size Comparison Tool.

Remember, the weight of an ILC will change depending on the lens you use at that moment. Here is the front view measurement comparison of the E-P3 compared to the K-S1.

Considering size and weight, the portability score of the E-P3 and K-S1 is 86 and 69 respectively.

Generally, it is very tough to see the difference in sensor dimensions purely by looking through a spec sheet. The picture underneath will offer you a more clear sense of the sensor sizing in the E-P3 and K-S1.

Clearly, both of the cameras posses different megapixel count and different sensor dimensions. The E-P3 featuring a smaller sensor will make getting shallow DOF tougher and the Pentax K-S1 will render greater detail as a result of its extra 8MP. Higher resolution will also help you crop pictures somewhat more aggressively. The more aged E-P3 will be disadvantaged in sensor innovation.