Sony a7R IV vs. Sony Alpha A99 II

Comparison

change cameras »
a7R IV image
vs
Alpha A99 II image
Sony a7R IV Sony Alpha A99 II
check price » check price »
Megapixels
61.00
42.40
Max. image resolution
9504 x 6336
7952 x 5304

Sensor

Sensor type
CMOS
CMOS
Sensor size
35.7 x 23.8 mm
35.9 x 24 mm
Sensor resolution
9566 x 6377
7976 x 5317
Diagonal
42.91 mm
43.18 mm
Sensor size comparison
Sensor size is generally a good indicator of the quality of the camera. Sensors can vary greatly in size. As a general rule, the bigger the sensor, the better the image quality.

Bigger sensors are more effective because they have more surface area to capture light. An important factor when comparing digital cameras is also camera generation. Generally, newer sensors will outperform the older.

Learn more about sensor sizes »

Actual sensor size

Note: Actual size is set to screen → change »
vs
1 : 1.01
(ratio)
Sony a7R IV Sony Alpha A99 II
Surface area:
849.66 mm² vs 861.60 mm²
Difference: 11.94 mm² (1%)
Alpha A99 II sensor is slightly bigger than a7R IV sensor (only 1% difference).
Note: You are comparing cameras of different generations. There is a 3 year gap between Sony a7R IV (2019) and Sony Alpha A99 II (2016). All things being equal, newer sensor generations generally outperform the older.
Pixel pitch
3.73 µm
4.5 µm
Pixel pitch tells you the distance from the center of one pixel (photosite) to the center of the next. It tells you how close the pixels are to each other.

The bigger the pixel pitch, the further apart they are and the bigger each pixel is. Bigger pixels tend to have better signal to noise ratio and greater dynamic range.
Difference: 0.77 µm (21%)
Pixel pitch of Alpha A99 II is approx. 21% higher than pixel pitch of a7R IV.
Pixel area
13.91 µm²
20.25 µm²
Pixel or photosite area affects how much light per pixel can be gathered. The larger it is the more light can be collected by a single pixel.

Larger pixels have the potential to collect more photons, resulting in greater dynamic range, while smaller pixels provide higher resolutions (more detail) for a given sensor size.
Relative pixel sizes:
vs
Pixel area difference: 6.34 µm² (46%)
A pixel on Sony Alpha A99 II sensor is approx. 46% bigger than a pixel on Sony a7R IV.
Pixel density
7.18 MP/cm²
4.94 MP/cm²
Pixel density tells you how many million pixels fit or would fit in one square cm of the sensor.

Higher pixel density means smaller pixels and lower pixel density means larger pixels.
Difference: 2.24 µm (45%)
Sony a7R IV has approx. 45% higher pixel density than Sony Alpha A99 II.
To learn about the accuracy of these numbers, click here.



Specs

Sony a7R IV
Sony Alpha A99 II
Crop factor
1.01
1
Total megapixels
62.50
43.60
Effective megapixels
61.00
42.40
Optical zoom
 
 
Digital zoom
Yes
Yes
ISO sensitivity
Auto, 100-32000 (expandable to 50-102400)
Auto, 100-25600 (expandable to 50-102400)
RAW
Manual focus
Normal focus range
Macro focus range
Focal length (35mm equiv.)
Aperture priority
Yes
Yes
Max. aperture
Max. aperture (35mm equiv.)
n/a
n/a
Metering
Multi, Center-weighted, Highlight-weighted, Average, Spot
Multi, Center-weighted, Spot
Exposure compensation
±5 EV (in 1/3 EV, 1/2 EV steps)
±5 EV (in 1/3 EV, 1/2 EV steps)
Shutter priority
Yes
Yes
Min. shutter speed
30 sec
30 sec
Max. shutter speed
1/8000 sec
1/8000 sec
Built-in flash
External flash
Viewfinder
Electronic
Electronic
White balance presets
9
10
Screen size
3"
3"
Screen resolution
1,440,000 dots
1,228,800 dots
Video capture
Max. video resolution
3840x2160 (30p/​25p/​24p)
3840x2160 (30p/25p/24p)
Storage types
SD/SDHC/SDXC
SD/SDHC/SDXC/MS PRO Duo
USB
USB 3.0 (5 GBit/sec)
USB 2.0 (480 Mbit/sec)
HDMI
Wireless
GPS
Battery
NP-FZ100 lithium-ion battery
NP-FM500H lithium-ion battery
Weight
665 g
849 g
Dimensions
128.9 x 96.4 x 77.5 mm
142.6 x 104.2 x 76.1 mm
Year
2019
2016




Choose cameras to compare

vs

Diagonal

Diagonal is calculated by the use of Pythagorean theorem:
Diagonal =  w² + h²
where w = sensor width and h = sensor height

Sony a7R IV diagonal

w = 35.70 mm
h = 23.80 mm
Diagonal =  35.70² + 23.80²   = 42.91 mm

Sony Alpha A99 II diagonal

w = 35.90 mm
h = 24.00 mm
Diagonal =  35.90² + 24.00²   = 43.18 mm


Surface area

Surface area is calculated by multiplying the width and the height of a sensor.

a7R IV sensor area

Width = 35.70 mm
Height = 23.80 mm

Surface area = 35.70 × 23.80 = 849.66 mm²

Alpha A99 II sensor area

Width = 35.90 mm
Height = 24.00 mm

Surface area = 35.90 × 24.00 = 861.60 mm²


Pixel pitch

Pixel pitch is the distance from the center of one pixel to the center of the next measured in micrometers (µm). It can be calculated with the following formula:
Pixel pitch =   sensor width in mm  × 1000
sensor resolution width in pixels

a7R IV pixel pitch

Sensor width = 35.70 mm
Sensor resolution width = 9566 pixels
Pixel pitch =   35.70  × 1000  = 3.73 µm
9566

Alpha A99 II pixel pitch

Sensor width = 35.90 mm
Sensor resolution width = 7976 pixels
Pixel pitch =   35.90  × 1000  = 4.5 µm
7976


Pixel area

The area of one pixel can be calculated by simply squaring the pixel pitch:
Pixel area = pixel pitch²

You could also divide sensor surface area with effective megapixels:
Pixel area =   sensor surface area in mm²
effective megapixels

a7R IV pixel area

Pixel pitch = 3.73 µm

Pixel area = 3.73² = 13.91 µm²

Alpha A99 II pixel area

Pixel pitch = 4.5 µm

Pixel area = 4.5² = 20.25 µm²


Pixel density

Pixel density can be calculated with the following formula:
Pixel density =  ( sensor resolution width in pixels )² / 1000000
sensor width in cm

One could also use this formula:
Pixel density =   effective megapixels × 1000000  / 10000
sensor surface area in mm²

a7R IV pixel density

Sensor resolution width = 9566 pixels
Sensor width = 3.57 cm

Pixel density = (9566 / 3.57)² / 1000000 = 7.18 MP/cm²

Alpha A99 II pixel density

Sensor resolution width = 7976 pixels
Sensor width = 3.59 cm

Pixel density = (7976 / 3.59)² / 1000000 = 4.94 MP/cm²


Sensor resolution

Sensor resolution is calculated from sensor size and effective megapixels. It's slightly higher than maximum (not interpolated) image resolution which is usually stated on camera specifications. Sensor resolution is used in pixel pitch, pixel area, and pixel density formula. For sake of simplicity, we're going to calculate it in 3 stages.

1. First we need to find the ratio between horizontal and vertical length by dividing the former with the latter (aspect ratio). It's usually 1.33 (4:3) or 1.5 (3:2), but not always.

2. With the ratio (r) known we can calculate the X from the formula below, where X is a vertical number of pixels:
(X × r) × X = effective megapixels × 1000000    →   
X =  effective megapixels × 1000000
r
3. To get sensor resolution we then multiply X with the corresponding ratio:

Resolution horizontal: X × r
Resolution vertical: X

a7R IV sensor resolution

Sensor width = 35.70 mm
Sensor height = 23.80 mm
Effective megapixels = 61.00
r = 35.70/23.80 = 1.5
X =  61.00 × 1000000  = 6377
1.5
Resolution horizontal: X × r = 6377 × 1.5 = 9566
Resolution vertical: X = 6377

Sensor resolution = 9566 x 6377

Alpha A99 II sensor resolution

Sensor width = 35.90 mm
Sensor height = 24.00 mm
Effective megapixels = 42.40
r = 35.90/24.00 = 1.5
X =  42.40 × 1000000  = 5317
1.5
Resolution horizontal: X × r = 5317 × 1.5 = 7976
Resolution vertical: X = 5317

Sensor resolution = 7976 x 5317


Crop factor

Crop factor or focal length multiplier is calculated by dividing the diagonal of 35 mm film (43.27 mm) with the diagonal of the sensor.
Crop factor =   43.27 mm
sensor diagonal in mm


a7R IV crop factor

Sensor diagonal in mm = 42.91 mm
Crop factor =   43.27  = 1.01
42.91

Alpha A99 II crop factor

Sensor diagonal in mm = 43.18 mm
Crop factor =   43.27  = 1
43.18

35 mm equivalent aperture

Equivalent aperture (in 135 film terms) is calculated by multiplying lens aperture with crop factor (a.k.a. focal length multiplier).

a7R IV equivalent aperture

Aperture is a lens characteristic, so it's calculated only for fixed lens cameras. If you want to know the equivalent aperture for Sony a7R IV, take the aperture of the lens you're using and multiply it with crop factor.

Crop factor for Sony a7R IV is 1.01

Alpha A99 II equivalent aperture

Aperture is a lens characteristic, so it's calculated only for fixed lens cameras. If you want to know the equivalent aperture for Sony Alpha A99 II, take the aperture of the lens you're using and multiply it with crop factor.

Since crop factor for Sony Alpha A99 II is 1, the equivalent aperture is aperture.

Enter your screen size (diagonal)

My screen size is  inches



Actual size is currently adjusted to screen.

If your screen (phone, tablet, or monitor) is not in diagonal, then the actual size of a sensor won't be shown correctly.