Pentax K20D vs Sony Alpha 550 — Which Is Better?
Side by side47 specifications |
Pentax · DSLR · 14.6 MP · APS-C
Pentax K20D
47
WINNER
|
Sony · DSLR · 14.2 MP · APS-C
Sony Alpha 550
44
SCORE
|
|---|---|---|
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| General | ||
Read the General ComparisonGeneralThe Pentax K20D and the Sony Alpha 550 are both APS-C CMOS DSLRs, announced in January 2008 and August 2009 respectively. They use different native lens systems, Pentax KAF and Sony Alpha DT, so any lenses you already own usually decide the practical starting point. The Sony is the lighter body at 632 g against 800 g for the Pentax, a difference of 168 g. The Pentax measures 142 x 101 x 70 mm, while the Sony takes a slightly deeper 137 x 104 x 84 mm shape. | ||
Released ⓘRefers to the year this camera was officially made available for sale. |
2008 | 2009 |
Announcement date ⓘRefers to the date the manufacturer publicly announced the upcoming release and general specs of this camera. |
January 23, 2008 | August 27, 2009 |
| Camera type |  DSLR | DSLR |
| Camera size | 142 x 101 x 70 mm | 137 x 104 x 84 mm |
| Camera weight | 800 g | 632 g |
| Optics | 49/100 | 48/100 |
Read the Optics ComparisonOpticsThe Sony Alpha 550 is the better pick for moving subjects, shooting at 7 fps against 3 fps on the K20D. Its sensitivity ceiling also reaches 12800 ISO, against 3200 on the Pentax, leaving more room to raise the setting when light falls. The Pentax counters with a base ISO of 100 versus 200 for wide apertures in daylight, and 11 autofocus points against 9. Resolution is a practical tie for cropping, at 14.6 versus 14.2 megapixels, giving almost identical room to crop a distant bird. Both combine APS-C CMOS sensors with in-body stabilisation, so any lens in each native mount gains stabilisation. Both also top out at a 1/4000 second shutter speed, and the K20D uses a pentaprism viewfinder where the A550 uses a pentamirror. | ||
Megapixels ⓘThe higher the number of megapixels, the more detail the cameras sensor can capture. |
14.6 MP050 | 14.2 MP050 |
Image resolution ⓘImage resolution is measured in pixels and megapixels, width by height. The higher the number, the higher its resolution. |
4672 x 3104 | 4592 x 3056 |
Sensor type ⓘThe camera sensor captures light and records the image. Sensors vary in physical size, the number of pixels, and quality. |
CMOS | CMOS |
Sensor size ⓘThe sensor size contributes to the overall quality as well as the dynamic and tonal range a camera can capture. As a rule of thumb, the more surface there is to read the light, the more information it will capture. |
16 x 23 | 15.6 x 23.5 |
Sensor format ⓘRefers to the most commonly used sensor sizes. |
 APS-C | APS-C |
Continuous shooting ⓘThe number of sequential frames per second the camera can write to the memory card when shooting in burst or continuous mode. |
3 fps045 | 7 fps045 |
Lens mount ⓘThe lens mount will tell you what type of lens range you can fit onto the camera body. Often the same camera company will have different lens ranges for different cameras. |
Pentax KAF | Sony Alpha DT |
Image processor ⓘThe image processor in the camera converts the information collected on the sensor for digital storage on the memory card. |
Prime | Bionz |
Aspect ratio ⓘThe aspect ratio refers to the proportional difference between width and height. The most popular aspect ratios are 3:2 and 4:3. |
 3:2 | 3:2 |
Min ISO ⓘRefers to the lowest native (or 'base') ISO setting. Lower ISO are less sensitive to light but make a cleaner image. |
10030200 | 20030200 |
Max ISO ⓘRefers to the highest native (or 'base') ISO setting. Higher ISO is necessary for low-light situations or night photography, but higher ISOs often introduce grain or noise. |
32003003280000 | 128003003280000 |
Min ISO (expanded) ⓘExpanded (or extended) ISO is a digitally enhanced feature available on some cameras. It allows you to push beyond the native ISO range if necessary. |
10030200 | 20030200 |
Max ISO (expanded) ⓘExpanded (or extended) ISO is a digitally enhanced feature available on some cameras. It allows you to push beyond the native ISO range if necessary. |
64003003280000 | 128003003280000 |
Minimum shutter speed ⓘThe minimum shutter speed will tell you the longest exposure your camera can take without using an external accessory. |
3044080 | 3044080 |
Max shutter speed ⓘThe maximum shutter speed tells you the length inside 1 second the camera will capture. These can sometimes be extended with accessories such as extra external batteries. |
400080032000 | 400080032000 |
Autofocus points ⓘAutofocus points show where the camera is focusing graphically as squares or brackets in Live View or on an electronic viewfinder. These points are also used for light meter readings. |
110300 | 90300 |
In-body stabilisation ⓘIn-body Stabilization means the camera has a certain technology embedded that counteracts camera shake. |
 Yes | Yes |
Viewfinder type ⓘThe viewfinder type is either electronic or optical. Electronic viewfinders will have a small screen in the viewfinder. Optical viewfinders will use prisms and mirrors to look through the lens. |
Optical (pentaprism) | Optical (pentamirror) |
| Viewfinder dots | N/A | N/A |
| Video | ||
Read the Video ComparisonVideoNeither camera records video, so motion clips are off the table with either body. The split for time-lapse shooters favours the K20D. It offers built-in interval shooting to capture a sunset or a building project frame by frame, while the A550 has no in-camera time-lapse function. | ||
Video ⓘIndicates if this camera is capable of recording video. |
✗ | ✗ |
Max video resolution ⓘThe best resolution this camera can capture video in. Modern cameras can capture up to 8K video. |
N/A | N/A |
Max video format ⓘVideo resolution measured by the greatest number of pixels possible in each frame, width by height. A higher resolution means more detail or clarity in your video. |
N/A | N/A |
Max video frame rate ⓘHow many frames per second your video will capture. Most cameras have options for multiple frame rates, depending on the resolution you shoot in. For a general video, 24p or 30p is the standard, but more serious filmmakers may need a higher frame rate for creative effect. |
N/A | N/A |
Timelapse built in ⓘA built in time-lapse mode will allow continuous shooting throughout a prolonged period of time to be compressed into a sped up video. |
 Yes | No |
Video file format ⓘDifferent cameras can record in various video file formats. The File format you record in can impact how you edit and use the files. |
N/A | N/A |
| Features | 47/100 | 41/100 |
Read the Features ComparisonFeaturesThe K20D's weather sealing makes it the better body for rain-soaked landscapes and dusty trails; the A550 offers none. The Sony's advantage sits at the screen, since its 3-inch LCD tilts for waist-level or overhead shooting and shows roughly four times the dots, at 921,600 against 230,000, on a larger panel than the Pentax's fixed 2.7-inch display. Both provide live view plus built-in and external flash support. Neither offers GPS, Wi-Fi, Bluetooth or touch control, so neither transfers images wirelessly and neither records location data automatically. | ||
Builtin flash ⓘA built-in flash will often be positioned right above the lens. This will automatically pop up when you activate it. |
 Yes | Yes |
External flash ⓘExternal flashes are often connected through a hot shoe at the top of a camera, or a cable at the side of the camera. |
 Yes | Yes |
GPS ⓘGPS features in a camera will include location metadata to each of your photographs. |
✗ | ✗ |
Weather sealing ⓘWeather sealing capabilities will give you more confidence when shooting in unfavourable conditions. |
 Yes | No |
| Screen type | LCD | LCD |
Touch screen ⓘTouchscreen allows you to change camera settings and access menus with a swipe of your finger, instead of using buttons. |
✗ | ✗ |
| Screen size | 2.7" | 3" |
Screen dots ⓘScreen dots indicate the resolution of the LCD screen by including each sub pixel. |
2300001150001500000 | 9216001150001500000 |
Flip screen ⓘA flip screen (or articulating screen) is a second screen which can flip out from the side or top of the camera. This rotating screen allows you more freedom to take photos at different angles. |
No |  Yes |
Live view ⓘLive View feature allows you to see a continuous live video of what is being seen through your lens. |
 Yes | Yes |
Wi-Fi ⓘBuilt-in Wi-Fi allows you to connect your camera and share images wirelessly. |
✗ | ✗ |
Bluetooth ⓘBluetooth capabilities allow you wireless control of your camera with other external devices. |
✗ | ✗ |
| Storage & battery | 27/100 | 27/100 |
Read the Storage & battery ComparisonStorage and BatteryBoth use a single card slot with no USB charging, so spare batteries stay part of the routine on either body. Rated battery life is close, at 500 shots for the Pentax against 480 for the Sony. The Sony accepts SD and SDHC cards plus Memory Stick Pro Duo and Pro-HG Duo, while the Pentax takes SD, SDHC and MMC. | ||
| Memory card | SD / SDHC / MMC | SD / SDHC, Memory Stick Pro Duo / Pro-HG Duo |
| Dual memory card slots | ✗ | ✗ |
| Battery type | D-LI50 | NP-FM500H |
Battery life ⓘApproximately how long this cameras battery will last measured by how many photographs you will be able to take. |
500 shots1505000 | 480 shots1505000 |
| USB charging | ✗ | ✗ |
Read: Verdict
Verdict
Pick the Sony Alpha 550 if you photograph action, from children's football to birds in flight, because its 7 fps rate captures the moments the 3 fps K20D can miss. Its higher ISO ceiling gives more room when light drops, and its tilting high-detail screen helps with low and high angle framing.
Pick the Pentax K20D for outdoor work in poor weather, for time-lapse projects, or when you prefer a pentaprism finder and a slightly higher 14.6 megapixel count. Both stabilise any mounted lens and neither records video, so the real choice is speed and screen on one side against sealing, finder and interval shooting on the other.