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 Nikon D3100 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). Nikon D3100 has external dimensions of 124 x 96 x 75 mm (4.88 x 3.78 x 2.95″) and weighs 505 g (1.11 lb / 17.81 oz) (including batteries).
Below you can see the front view size comparison of Sony A7S and Nikon D3100. Sony A7S is 2mm shorter and 27mm thinner than Nikon D3100 but it is also 3mm wider.
![Sony A7S vs Nikon D3100 Camera Size Comparison - Front View]()
Comparison image of Sony A7S and Nikon D3100 Size, Weight and External Dimensions - Front View
Here is the back view size comparison of Sony A7S and Nikon D3100.
![Sony A7S vs Nikon D3100 Camera Size Comparison - Back View]()
Comparison image of Sony A7S and Nikon D3100 Size and Weight - Back View
Now lets look at the top view comparison of Sony A7S and Nikon D3100.
![Sony A7S vs Nikon D3100 Camera Size Comparison - Top View]()
Top View Comparison image of Sony A7S and Nikon D3100 Size
Weight is another important factor especially when deciding on a camera that you want to carry with you all day.
Sony A7S is 16g lighter than the Nikon D3100 but we don't think this will make a significant difference.
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 Nikon D3100 has a smaller APS-C sensor, Nikon D3100'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
With its weather sealed body, we believe that A7S has a big advantage over D3100 which doesn't provide any kind of environmental sealing.
LCD Screen Size and Features
Sony A7S and Nikon D3100's LCD screens has the same diagonal size of 3.
On the other hand, Sony A7S features a
Tilting screen where you can change the angle of the screen to make it easier to shoot from waist or over the head levels whereas the Nikon D3100 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, Nikon D3100 has a 14.0MP APS-C (23.1 x 15.4 mm ) sized CMOS sensor and features Expeed 2 processor.
Below you can see the A7S and D3100 sensor size comparison.
![Sony A7S vs Nikon D3100 Sensor Size Comparison]()
Sensor Size and Resolution Comparison image of Sony A7S and Nikon D3100 Cameras
As seen above, Sony A7S has a 2.4x Larger sensor area than Nikon D3100. 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 Nikon D3100 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, 20 points higher than D3100.
| Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
|
Sony A7S |
87 |
23.9 bits |
13.2 Evs |
3702 ISO |
|
Nikon D3100 |
67 |
22.5 bits |
11.3 Evs |
919 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 Nikon D3100 has an advantage over Sony A7S There are 309 lenses for Nikon D3100's Nikon F mount, on the other hand there are only 128 lenses for Sony A7S's Sony E lens mount.
Another important factor is the availability of image stabilization. None of these bodies have sensor based image stabilization so you have to buy lenses with Optical stabilization feature. Currently there are 31 lenses for Sony E mount and 106 lenses for Nikon F mount with IS.
| Lens Type |
# of Sony A7S Lenses |
# of Nikon D3100 Lenses |
| Standard Zoom |
12 (9 Full Frame) |
33 |
| Standard Prime |
18 (9 Full Frame) |
21 |
| Wideangle Zoom |
7 (6 Full Frame) |
33 |
| Wideangle Prime |
42 (26 Full Frame) |
48 |
| Telephoto Zoom |
9 (7 Full Frame) |
53 |
| Telephoto Prime |
18 (14 Full Frame) |
45 |
| SuperZoom |
8 (1 Full Frame) |
30 |
| Wideangle Fisheye Prime |
2 (0 Full Frame) |
8 |
| Macro Prime |
8 (7 Full Frame) |
26 |
| Perspective Control Prime |
2 (2 Full Frame) |
11 |
| Telephoto Mirror Prime |
n/a |
1 |
| TOTAL |
128 (81 Full Frame) |
309 |
Now let's compare some sample lenses from each mount with typical Focal ranges for Sony A7S and Nikon D3100 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 Nikon D3100 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
Nikon D3100 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 (23.1 x 15.4 mm) sensor
Optical Built-in Viewfinder
Good Ergonomics&Handling
Average Resolution Sensor: 14.0MP
No Image Stabilization
Read the details
Sony A7S for Street Photography
Nikon D3100 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 (23.1 x 15.4 mm) sensor
Optical Built-in Viewfinder
Live-view
Face-Detection Focusing
No Image Stabilization
Large Body
Read the details
Sony A7S for Sports Photography
Nikon D3100 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
Optical Built-in Viewfinder
Good Ergonomics&Handling
Fast Max shutter speed: 1/4000s
1 Cross Type Focus sensors
11 Focus Points
Good Battery Life: 550 shots
No Image Stabilization
Slow Continuous Shooting: 3.0fps
Environmental Sealings
Read the details
Sony A7S for Daily Photography
Nikon D3100 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 (23.1 x 15.4 mm) sensor
Large Body
505g
Body Thickness 75mm
Read the details
Sony A7S for Landscape Photography
Nikon D3100 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 (23.1 x 15.4 mm) sensor
Live-view
Average Resolution Sensor: 14.0MP
No Environmental Sealings
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 Nikon D3100, 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 Nikon D3100 scores compare:
Sony A7S
Ranked
#39 out of 86 in SLR-style mirrorless cameras
Ranked
#71 out of 1220 in all Cameras
Nikon D3100
Ranked
#50 out of 78 in Compact SLR cameras
Ranked
#360 out of 1220 in all Cameras
Sony A7S is the clear winner of this comparison. It has a higher Overall Score and beats Nikon D3100 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 |
Nikon D3100 |
| Brand |
Sony |
Nikon |
| Announced |
2014-04-06 |
2010-12-21 |
| Body Type |
SLR-style mirrorless |
Compact SLR |
Sensor |
|
|
| Type |
CMOS |
CMOS |
| Size |
Full frame |
APS-C |
| Dimensions |
35.8 x 23.9 mm |
23.1 x 15.4 mm |
| Area |
855.62mm2 |
355.74mm2 |
| Megapixels |
12 megapixels |
14 megapixels |
| Max Resolution |
4240 x 2832 |
4608 x 3072 |
| Max Native Light sensitivity |
409,600 ISO |
3,200 ISO |
| Max Boosted Light Sensitivity |
- |
12800 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 |
Nikon F |
| Number of Available Lenses |
128 |
309 |
Screen |
|
|
| Type |
Tilting |
Fixed type |
| Size |
3 |
3" |
| Resolution |
1,230k dots |
230k dots |
| Touch Screen |
|
|
Viewfinder |
|
|
| Viewfinder |
Electronic |
Optical (pentamirror) |
| Viewfinder Resolution |
2,359k dots |
no electronic viewfinder |
| Viewfinder Coverage |
100% |
95% |
| Viewfinder Magnification |
0.71x |
0.53x |
Photography Features |
|
|
| Max Mechanical Shutter |
1/8000s |
1/4000s |
| Shutter Priority |
|
|
| Aperture Priority |
|
|
| Manual Exposure Mode |
|
|
| Custom White Balance |
|
|
| Image Stabilization |
No |
No |
| Built-in Flash |
|
|
| Flash Range |
no built-in flash |
12.00 m (at ISO 100) |
| Max Flash Sync |
n/a |
1/200s |
| 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 |
1920 x 1080 |
| Video Formats |
MPEG-4, AVCHD, XAVC |
MPEG-4 |
| Microphone Port |
|
|
| Headphone Port |
|
|
Connectivity |
|
|
| Wireless Connectivity |
Built-In |
Eye-Fi Connected |
| HDMI |
|
|
Physical |
|
|
| Environmental Sealing |
|
|
| Weight |
489g |
505g |
| Dimensions |
127 x 94 x 48mm |
124 x 96 x 75mm |
| Battery Life |
360 shots |
550 shots |
Other Features |
|
|
| Timelapse Recording |
With Downloadable App |
|
| GPS |
None |
Optional |
DxO Sensor Scores |
|
|
| DxO Overall Score |
87 |
67 |
| DxO Color Depth |
23.9 |
22.5 |
| DxO Dynamic Range |
13.2 |
11.3 |
| DxO Low Light ISO |
3702 |
919 |
|
Report a correction |
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