Size and weight is a big decision factor when you are trying to find the ideal camera for your needs.
In this section, We are going to illustrate Sony A7S and Pentax K20D side-by-side from the front, back and top in their relative dimensions. Sony A7S has external dimensions of 127 x 94 x 48 mm (5 x 3.7 x 1.89″) and weighs 489 g (1.08 lb / 17.25 oz) (including batteries). Pentax K20D has external dimensions of 142 x 101 x 70 mm (5.59 x 3.98 x 2.76″) and weighs 800 g (1.76 lb / 28.22 oz) (including batteries).
Below you can see the front view size comparison of Sony A7S and Pentax K20D. Sony A7S is clearly the smaller of the two cameras. Its body is 15mm narrower, 7mm shorter and 22mm thinner than Pentax K20D.
![Sony A7S vs Pentax K20D Camera Size Comparison - Front View]()
Comparison image of Sony A7S and Pentax K20D Size, Weight and External Dimensions - Front View
Here is the back view size comparison of Sony A7S and Pentax K20D.
![Sony A7S vs Pentax K20D Camera Size Comparison - Back View]()
Comparison image of Sony A7S and Pentax K20D Size and Weight - Back View
Now lets look at the top view comparison of Sony A7S and Pentax K20D.
![Sony A7S vs Pentax K20D Camera Size Comparison - Top View]()
Top View Comparison image of Sony A7S and Pentax K20D Size
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Sony A7S is significantly lighter (311g ) than the Pentax K20D which may become a big advantage especially on long walking trips.
Also keep in mind that body weight is not the only deciding factor when comparing two interchangeable camera bodies, you have to also take into account the lenses that you will be using with these bodies. Since Sony A7S has a Full frame sensor and Pentax K20D has a smaller APS-C sensor, Pentax K20D's lenses for a similar focal length and aperture will generally be lighter and smaller than the Sony A7S lenses.
Weight Comparison
DSLR Cameras
Thickness Comparison
DSLR Cameras
Weather Sealing
Both A7S and K20D have weather sealings in their body, making them resistant to water and dust.
LCD Screen Size and Features
Sony A7S's 3 LCD screen is slightly larger than Pentax K20D's 2.7" screen.
In addition to the size advantage, Sony A7S LCD screen also has a
Tilting feature where you can change the angle of the screen to make it easier to shoot from waist or over the head levels. On the other hand, Pentax K20D has a fixed type screen which provides less flexibility in shooting positions compared to A7S.
Sony A7S has a 12.0MP Full frame (35.8 x 23.9 mm ) sized CMOS sensor and features Bionz X processor. On the other hand, Pentax K20D has a 15.0MP APS-C (23.4 x 15.6 mm ) sized CMOS sensor .
Below you can see the A7S and K20D sensor size comparison.
![Sony A7S vs Pentax K20D Sensor Size Comparison]()
Sensor Size and Resolution Comparison image of Sony A7S and Pentax K20D Cameras
As seen above, Sony A7S has a 2.3x Larger sensor area than Pentax K20D. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.
DxOMark Sensor Scores
Both Sony A7S and Pentax K20D sensors have been tested by DxoMark. DxoMark scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Of the two cameras that we are comparing, A7S has scored 87, 22 points higher than K20D.
| Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
|
Sony A7S |
87 |
23.9 bits |
13.2 Evs |
3702 ISO |
|
Pentax K20D |
65 |
22.9 bits |
11.1 Evs |
639 ISO |
Number of available lenses is a big decision factor while choosing your interchangeable lens camera. When we look at the available lenses for these two cameras, we see that Pentax K20D has an advantage over Sony A7S There are 151 lenses for Pentax K20D's Pentax KAF2 mount, on the other hand there are only 122 lenses for Sony A7S's Sony E lens mount.
Another important factor is the availability of image stabilization. Pentax K20D has a big advantage in this regard because it has a sensor based image stabilization which means that all the lenses mounted to this body will be stabilized. On the other hand, Sony A7S doesn't have this feature so you have to buy a lens with optical stabilization feature. Currently there are 30 lenses for Sony E mount with Optical Image Stabilization features.
| Lens Type |
# of Sony A7S Lenses |
# of Pentax K20D Lenses |
| Standard Zoom |
11 (8 Full Frame) |
22 |
| Standard Prime |
18 (9 Full Frame) |
20 |
| Wideangle Zoom |
7 (6 Full Frame) |
12 |
| Wideangle Prime |
39 (23 Full Frame) |
24 |
| Telephoto Zoom |
9 (7 Full Frame) |
21 |
| Telephoto Prime |
18 (14 Full Frame) |
12 |
| SuperZoom |
8 (1 Full Frame) |
15 |
| Wideangle Fisheye Prime |
2 (0 Full Frame) |
3 |
| Macro Prime |
8 (7 Full Frame) |
14 |
| Perspective Control Prime |
2 (2 Full Frame) |
8 |
| Telephoto Mirror Prime |
n/a |
n/a |
| TOTAL |
122 (77 Full Frame) |
151 |
Now let's compare some sample lenses from each mount with typical Focal ranges for Sony A7S and Pentax K20D to see how these lenses compares:
Fast Standard Zoom Lenses
Fast Tele Zoom Equivalent Lenses
Fast Normal Prime Equivalent Lenses
Fast Wideangle Zoom Equivalent Lenses
24-105mm f4 Equivalent Lenses
Super-Tele Zoom Equivalent Lenses
In this section, we rank and compare Sony A7S and Pentax K20D for five different photography types in order to make your decision process easier in case you are specifically interested in one or more of these areas.
Sony A7S for Portrait Photography
Pentax K20D for Portrait Photography
Large Full frame (35.8 x 23.9 mm) sensor
Electronic Built-in Viewfinder
Good Ergonomics&Handling
Average Resolution Sensor: 12.0MP
No Image Stabilization
Read the details
Large APS-C (23.4 x 15.6 mm) sensor
Image Stabilization
Optical Built-in Viewfinder
Good Ergonomics&Handling
Average Resolution Sensor: 15.0MP
Read the details
Sony A7S for Street Photography
Pentax K20D for Street Photography
Large Full frame (35.8 x 23.9 mm) sensor
Electronic Built-in Viewfinder
Live-view
Face-Detection Focusing
Tilting LCD Screen
Medium sized Body
No Image Stabilization
Read the details
Large APS-C (23.4 x 15.6 mm) sensor
Image Stabilization
Optical Built-in Viewfinder
Live-view
Large Body
Read the details
Sony A7S for Sports Photography
Pentax K20D for Sports Photography
Electronic Built-in Viewfinder
Good Ergonomics&Handling
Environmental Sealings
Fast Max shutter speed: 1/8000s
25 Focus Points
Good Low Light ISO
Wireless Connection
Average Continuous Shooting: 5.0fps
No Image Stabilization
Read the details
Image Stabilization
Optical Built-in Viewfinder
Good Ergonomics&Handling
Environmental Sealings
Fast Max shutter speed: 1/4000s
11 Focus Points
Slow Continuous Shooting: 3.0fps
Read the details
Sony A7S for Daily Photography
Pentax K20D for Daily Photography
Large Full frame (35.8 x 23.9 mm) sensor
Environmental Sealings
Medium size Body
489g
Body Thickness 48mm
Read the details
Large APS-C (23.4 x 15.6 mm) sensor
Environmental Sealings
Large Body
800g
Body Thickness 70mm
Read the details
Sony A7S for Landscape Photography
Pentax K20D for Landscape Photography
Large Full frame (35.8 x 23.9 mm) sensor
Environmental Sealings
Live-view
Average Resolution Sensor: 12.0MP
Read the details
Large APS-C (23.4 x 15.6 mm) sensor
Environmental Sealings
Live-view
Average Resolution Sensor: 15.0MP
Read the details
You may have already made your decision about which camera suits better for your needs and your budget so far but in case you wonder how we rated Sony A7S and Pentax K20D, below you can find their scores in five different aspects.
Our Decision Algorithm dynamically scores cameras using 63 different specs, current price and DxO Mark scores (where possible) in order to make a more objective and consistent comparison.
Here is a summary of how Sony A7S and Pentax K20D scores compare:
Sony A7S
Ranked
#38 out of 85 in SLR-style mirrorless cameras
Ranked
#70 out of 1218 in all Cameras
Pentax K20D
Ranked
#58 out of 94 in Mid-size SLR cameras
Ranked
#393 out of 1218 in all Cameras
Sony A7S is the clear winner of this comparison. It has a higher Overall Score and beats Pentax K20D in all criteria. It has better general image quality, more features, more compact body and offers more value for the money
| General |
Sony Alpha A7S |
Pentax K20D |
| Brand |
Sony |
Pentax |
| Announced |
2014-04-06 |
2008-06-25 |
| Body Type |
SLR-style mirrorless |
Mid-size SLR |
Sensor |
|
|
| Type |
CMOS |
CMOS |
| Size |
Full frame |
APS-C |
| Dimensions |
35.8 x 23.9 mm |
23.4 x 15.6 mm |
| Area |
855.62mm2 |
365.04mm2 |
| Megapixels |
12 megapixels |
15 megapixels |
| Max Resolution |
4240 x 2832 |
4672 x 3104 |
| Max Native Light sensitivity |
409,600 ISO |
3,200 ISO |
| Max Boosted Light Sensitivity |
- |
6400 ISO |
| Min Native Light sensitivity |
100 ISO |
100 ISO |
| RAW Support |
|
|
Autofocus |
|
|
| AF Touch |
|
|
| AF Continuous |
|
|
| AF Single |
|
|
| AF Tracking |
|
|
| AF Selective |
|
|
| AF Center |
|
|
| AF Multi Area |
|
|
| AF Live View |
|
|
| AF Face Detection |
|
|
| AF Contrast Detection |
|
|
| AF Phase Detection |
|
|
| Number of Focus Points |
25 |
11 |
Lens |
|
|
| Manual Focus |
|
|
| Lens Mount |
Sony E |
Pentax KAF2 |
| Number of Available Lenses |
122 |
151 |
Screen |
|
|
| Type |
Tilting |
Fixed type |
| Size |
3 |
2.7" |
| Resolution |
1,230k dots |
230k dots |
| Touch Screen |
|
|
Viewfinder |
|
|
| Viewfinder |
Electronic |
Optical (pentaprism) |
| Viewfinder Resolution |
2,359k dots |
no electronic viewfinder |
| Viewfinder Coverage |
100% |
95% |
| Viewfinder Magnification |
0.71x |
0.64x |
Photography Features |
|
|
| Max Mechanical Shutter |
1/8000s |
1/4000s |
| Shutter Priority |
|
|
| Aperture Priority |
|
|
| Manual Exposure Mode |
|
|
| Custom White Balance |
|
|
| Image Stabilization |
No |
Sensor-shift |
| Built-in Flash |
|
|
| Flash Range |
no built-in flash |
13.00 m (at ISO 100) |
| Max Flash Sync |
no built-in flash |
1/180s |
| External Flash |
|
|
| Continuous Shooting |
5.0 fps |
3.0 fps |
| Multi-Segment |
|
|
| Average |
|
|
| Spot |
|
|
| Partial |
|
|
| AF-Area |
|
|
| Center Weighted |
|
|
| AE Bracketing |
|
|
| WB Bracketing |
|
|
Video Features |
|
|
| Max Video Resolution |
3840 x 2160 |
None |
| Video Formats |
MPEG-4, AVCHD, XAVC |
n/a |
| Microphone Port |
|
|
| Headphone Port |
|
|
Connectivity |
|
|
| Wireless Connectivity |
Built-In |
None |
| HDMI |
|
|
Physical |
|
|
| Environmental Sealing |
|
|
| Weight |
489g |
800g |
| Dimensions |
127 x 94 x 48mm |
142 x 101 x 70mm |
| Battery Life |
360 shots |
n/a |
Other Features |
|
|
| Timelapse Recording |
With Downloadable App |
|
| GPS |
None |
None |
DxO Sensor Scores |
|
|
| DxO Overall Score |
87 |
65 |
| DxO Color Depth |
23.9 |
22.9 |
| DxO Dynamic Range |
13.2 |
11.1 |
| DxO Low Light ISO |
3702 |
639 |
|
Report a correction |
Report a correction |