Pentax 645D versus Sony A99 II
The Pentax 645D and the Sony Alpha ALT-A99 II are two professional cameras that were announced, respectively, in March 2010 and September 2016. Both are DSLR (Digital Single Lens Reflex) cameras that are based on a medium format (645D) and a full frame sensor. The Pentax has a resolution of 39.5 megapixel, whereas the Sony provides 42.2 MP.
An illustration of the physical size and weight of the Pentax 645D and the Sony A99 II is provided in the side-by-side display below. Three successive views from the front, the top, and the rear are shown. All width, height and depth dimensions are rounded to the nearest millimeter. If you prefer, you can also use the toggle button to switch to a comparison in percentage terms (in this case, the camera on the left – the 645D – represents the basis or 100 percent across all the size and weight measures).
If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A99 II is notably smaller (19 percent) than the Pentax 645D. Moreover, the A99 II is substantially lighter (43 percent) than the 645D. In this context, it is worth noting that both cameras are splash and dust-proof and can, hence, be used in inclement weather conditions or harsh environments.
The above size and weight comparisons are to some extent incomplete since they do not consider the interchangeable lenses that both of these cameras require. Hence, you might want to study the specifications of available lenses in order to get the full picture of the size and weight of the two camera systems.
The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. If you want to switch the focus of the display and review another camera pair, just select a new right or left comparator from among the camera models in the table. Alternatively, you can also move across to the CAM-parator tool and choose from the broad selection of possible comparisons there.
|Camera Body Specifications
|Pentax 645D (⇒ rgt)||156 mm||117 mm||119 mm||1480 g||800||YES||2010||9,995||discont.||check|
|Sony A99 II (⇒ lft)||143 mm||104 mm||76 mm||849 g||490||YES||2016||3,199||latest||check|
|Canon 1D X (⇒ lft | rgt)||158 mm||168 mm||83 mm||1551 g||1120||YES||2011||6,799||discont.||check|
|Canon 1D Mark IV (⇒ lft | rgt)||156 mm||157 mm||80 mm||1230 g||1500||YES||2009||4,999||discont.||check|
|Leica S Typ 006 (⇒ lft | rgt)||160 mm||120 mm||80 mm||1260 g||..||YES||2012||21,950||discont.||check|
|Nikon D850 (⇒ lft | rgt)||146 mm||124 mm||79 mm||1005 g||1840||YES||2017||3,299||latest||check|
|Nikon D810 (⇒ lft | rgt)||146 mm||123 mm||82 mm||980 g||1200||YES||2014||3,299||discont.||check|
|Nikon D800 (⇒ lft | rgt)||146 mm||123 mm||82 mm||1000 g||900||YES||2012||2,999||discont.||check|
|Nikon D3S (⇒ lft | rgt)||160 mm||157 mm||88 mm||1240 g||4200||YES||2009||5,199||discont.||check|
|Pentax K-1 (⇒ lft | rgt)||137 mm||110 mm||86 mm||1010 g||760||YES||2016||1,799||latest||check|
|Pentax 645Z (⇒ lft | rgt)||156 mm||117 mm||123 mm||1550 g||650||YES||2014||8,499||latest||check|
|Sony A7R III (⇒ lft | rgt)||127 mm||96 mm||74 mm||650 g||650||YES||2017||3,199||latest||check|
|Sony A7R II (⇒ lft | rgt)||127 mm||96 mm||60 mm||625 g||290||YES||2015||3,199||discont.||check|
|Sony A7S II (⇒ lft | rgt)||127 mm||96 mm||60 mm||627 g||370||YES||2015||2,999||latest||check|
|Sony A7R (⇒ lft | rgt)||127 mm||94 mm||48 mm||465 g||340||YES||2013||2,299||discont.||check|
|Sony A99 (⇒ lft | rgt)||147 mm||111 mm||78 mm||812 g||500||YES||2012||2,799||discont.||check|
The listed prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The A99 II was launched at a markedly lower price (by 68 percent) than the 645D, which puts it into a different market segment. Usually, retail prices stay at first close to the launch price, but after several months, discounts become available. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.
The imaging sensor is at the core of digital cameras and its size is one of the main determining factors of image quality. A large sensor will generally have larger individual pixels that offer better low-light sensitivity, provide wider dynamic range, and have richer color depth than smaller pixels in a sensor of the same technological generation. Moreover, a large sensor camera will give the photographer more control over depth-of-field in the image and, thus, the ability to better isolate a subject from the background. On the downside, larger sensors tend to be more expensive and lead to bigger and heavier cameras and lenses.
Of the two cameras under consideration, the Pentax 645D features a medium format sensor and the Sony A99 II a full frame sensor. The sensor area in the A99 II is 41 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 0.79 and 1.0. The sensor in the 645D has a native 4:3 aspect ratio, while the one in the A99 II offers a 3:2 aspect.
Despite having a smaller sensor, the A99 II offers a slightly higher resolution of 42.2 megapixel, compared with 39.5 MP of the 645D. This megapixel advantage comes at the cost of a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 4.52μm versus 6.06μm for the 645D). However, it should be noted that the A99 II is much more recent (by 6 years and 6 months) than the 645D, and its sensor will have benefitted from technological advances during this time that make it possible to gather light more efficiently. Coming back to sensor resolution, it should be mentioned that neither of the two cameras has an anti-alias filter installed, so they are able to capture all the detail the sensor resolves.
Consistent information on actual sensor performance is available from DXO Mark for most cameras. This service assesses and scores the color depth ("DXO Portrait"), dynamic range ("DXO Landscape"), and low-light sensitivity ("DXO Sports") of camera sensors, and also publishes an overall camera score. Of the two cameras under consideration, the A99 II has a markedly higher DXO score than the 645D (overall score 10 points higher), which will translate into better image quality. The advantage is based on 0.8 bits higher color depth, 0.8 EV in additional dynamic range, and 0.9 stops in additional low light sensitivity. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.
|Pentax 645D (⇒ rgt)||Medium Format||39.5||7264||5440||no||24.6||12.6||1262||82|
|Sony A99 II (⇒ lft)||Full Frame||42.2||7952||5304||4K/30p||25.4||13.4||2317||92|
|Canon 1D X (⇒ lft | rgt)||Full Frame||17.9||5184||3456||1080/30p||23.8||11.8||2786||82|
|Canon 1D Mark IV (⇒ lft | rgt)||APS-H||16.0||4896||3264||1080/30p||22.8||12.0||1320||74|
|Leica S Typ 006 (⇒ lft | rgt)||Medium Format||37.5||7500||5000||no||23.9||12.2||824||76|
|Nikon D850 (⇒ lft | rgt)||Full Frame||45.4||8256||5504||4K/30p||26.4||14.8||2660||100|
|Nikon D810 (⇒ lft | rgt)||Full Frame||36.2||7360||4912||1080/60p||25.7||14.8||2853||97|
|Nikon D800 (⇒ lft | rgt)||Full Frame||36.2||7360||4912||1080/30p||25.3||14.4||2853||95|
|Nikon D3S (⇒ lft | rgt)||Full Frame||12.1||4256||2832||720/24p||23.5||12.0||3253||82|
|Pentax K-1 (⇒ lft | rgt)||Full Frame||36.2||7360||4912||1080/60i||25.4||14.6||3280||96|
|Pentax 645Z (⇒ lft | rgt)||Medium Format||51.1||8256||6192||1080/60i||26.0||14.7||4505||101|
|Sony A7R III (⇒ lft | rgt)||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100|
|Sony A7R II (⇒ lft | rgt)||Full Frame||42.2||7952||5304||4K/30p||26.0||13.9||3434||98|
|Sony A7S II (⇒ lft | rgt)||Full Frame||12.0||4240||2832||4K/30p||23.6||13.3||2993||85|
|Sony A7R (⇒ lft | rgt)||Full Frame||36.2||7360||4912||1080/60p||25.6||14.1||2746||95|
|Sony A99 (⇒ lft | rgt)||Full Frame||24.0||6000||4000||1080/60p||25.0||14.0||1555||89|
Many modern cameras cannot only take still pictures, but also record videos. The A99 II indeed provides for movie recording, while the 645D does not. The highest resolution format that the A99 II can use is 4K/30p.
Apart from body and sensor, cameras can and do differ across a range of features. For example, the A99 II has an electronic viewfinder (2400k dots), while the 645D has an optical one. Both systems have their advantages, with the electronic viewfinder making it possible to project supplementary shooting information into the framing view, whereas the optical viewfinder offers lag-free viewing and a very clear framing image. The following table reports on some other key feature differences and similarities of the Pentax 645D, the Sony A99 II, and comparable cameras. If needed, the dpreview camera hub, for example, contains further detail on the cameras' specs.
|Pentax 645D (⇒ rgt)||optical||YES||3.0||921||fixed||no||4000||1.1||no||no|
|Sony A99 II (⇒ lft)||2400||YES||3.0||1229||full-flex||no||8000||12.0||no||YES|
|Canon 1D X (⇒ lft | rgt)||optical||YES||3.2||1040||fixed||no||8000||14.0||no||no|
|Canon 1D Mark IV (⇒ lft | rgt)||optical||YES||3.0||920||fixed||no||8000||10.0||no||no|
|Leica S Typ 006 (⇒ lft | rgt)||optical||YES||3.0||922||fixed||no||4000||1.5||no||no|
|Nikon D850 (⇒ lft | rgt)||optical||YES||3.2||2359||tilting||YES||8000||9.0||no||no|
|Nikon D810 (⇒ lft | rgt)||optical||YES||3.2||1229||fixed||no||4000||5.0||12||no|
|Nikon D800 (⇒ lft | rgt)||optical||YES||3.2||921||fixed||no||8000||4.0||12||no|
|Nikon D3S (⇒ lft | rgt)||optical||YES||3.0||921||fixed||no||8000||11.0||no||no|
|Pentax K-1 (⇒ lft | rgt)||optical||YES||3.2||1037||full-flex||no||8000||4.4||no||YES|
|Pentax 645Z (⇒ lft | rgt)||optical||YES||3.2||1037||tilting||no||4000||3.0||no||no|
|Sony A7R III (⇒ lft | rgt)||3686||no||3.0||1440||tilting||YES||8000||10.0||no||YES|
|Sony A7R II (⇒ lft | rgt)||2400||no||3.0||1229||tilting||no||8000||5.0||no||YES|
|Sony A7S II (⇒ lft | rgt)||2400||no||3.0||1229||tilting||no||8000||5.0||no||YES|
|Sony A7R (⇒ lft | rgt)||2400||no||3.0||1230||tilting||no||8000||4.0||no||no|
|Sony A99 (⇒ lft | rgt)||2359||YES||3.0||1229||full-flex||no||8000||6.0||no||YES|
The A99 II is a current model that online retailers, such as amazon, will have in stock. In contrast, the 645D has been discontinued (but it can be found pre-owned on ebay). As a replacement in the same line of cameras, the 645D was succeeded by the Pentax 645Z.
So how do things add up? Is the Pentax 645D better than the Sony A99 II or vice versa? A synthesis of the relative strong points of each of the models is listed below.
Reasons to prefer the Pentax 645D:
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Longer lasting: Can take more shots (800 versus 490) on a single battery charge.
- More heavily discounted: Has been available for much longer (launched in March 2010).
Arguments in favor of the Sony Alpha ALT-A99 II:
- More detail: Has more megapixels (42.2 vs 39.5MP), which boosts linear resolution by 5%.
- Better image quality: Scores markedly higher (10 points) in the DXO overall evaluation.
- More dynamic range: Captures a broader range of light and dark details (0.8 EV of extra DR).
- Better low-light sensitivity: Can shoot in dim conditions (0.9 stops ISO advantage).
- Broader imaging potential: Can capture not only stills but also 4K/30p video.
- More framing info: Has an electronic viewfinder that displays shooting data.
- More detailed LCD: Has a higher resolution rear screen (1229k vs 921k dots).
- More flexible LCD: Has full-flex screen for odd-angle shots in portrait or landscape orientation.
- Faster shutter: Has higher mechanical shutter speed (8000/sec vs 4000/sec) to freeze action.
- Faster burst: Shoots at higher frequency (12 vs 1.1 flaps/sec) to capture the decisive moment.
- More compact: Is smaller (143x104mm vs 156x117mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 631g or 43 percent) and is thus easier to take along.
- Sharper images: Has stabilization technology build-in to reduce the impact of hand-shake.
- More affordable: Was introduced into a lower priced category (68 percent cheaper at launch).
- More modern: Reflects 6 years and 6 months of technical progress since the 645D launch.
If the number of relative strengths (bullet points above) is taken as a guide, the A99 II is the clear winner of the contest (15 : 3 points). However, the pertinence of the various camera strengths will differ across photographers, so that you might want to weigh individual camera traits according to their importance for your own imaging needs.
In any case, while the comparison of the spec-sheets of cameras can offer a general idea of their imaging potential, it says nothing about, for example, the handling, responsiveness, and overall imaging quality of the 645D and the A99 II in practical situations. User reviews that are available, for instance, at amazon can sometimes shed light on these issues, but such feedback is all too often partial, inconsistent, and inaccurate. This is why hands-on reviews by experts are important. The adjacent table relays the overall verdicts of several of the most popular camera review sites. The detailed reviews can be accessed, respectively, on the websites of cameralabs.com, dpreview.com, ephotozine.com, imaging-resource.com, and photographyblog.com.
|Pentax 645D (⇒ rgt)||-||-||-||4.5/5||-||2010||9,995||discont.||check|
|Sony A99 II (⇒ lft)||-||85/100 Silver||4.5/5||4.5/5||4.5/5||2016||3,199||latest||check|
|Canon 1D X (⇒ lft | rgt)||-||-||4.5/5||4.5/5||4.5/5||2011||6,799||discont.||check|
|Canon 1D Mark IV (⇒ lft | rgt)||-||89/100 Gold||-||5/5||-||2009||4,999||discont.||check|
|Leica S Typ 006 (⇒ lft | rgt)||-||-||-||-||-||2012||21,950||discont.||check|
|Nikon D850 (⇒ lft | rgt)||HiRec||89/100 Gold||4.5/5||5/5||5/5||2017||3,299||latest||check|
|Nikon D810 (⇒ lft | rgt)||-||86/100 Gold||5/5||4.5/5||4.5/5||2014||3,299||discont.||check|
|Nikon D800 (⇒ lft | rgt)||HiRec||82/100 Gold||5/5||5/5||5/5||2012||2,999||discont.||check|
|Nikon D3S (⇒ lft | rgt)||-||89/100 Gold||4.5/5||5/5||5/5||2009||5,199||discont.||check|
|Pentax K-1 (⇒ lft | rgt)||-||84/100 Silver||5/5||4.5/5||5/5||2016||1,799||latest||check|
|Pentax 645Z (⇒ lft | rgt)||-||-||4.5/5||5/5||5/5||2014||8,499||latest||check|
|Sony A7R III (⇒ lft | rgt)||HiRec||90/100 Gold||4.5/5||5/5||5/5||2017||3,199||latest||check|
|Sony A7R II (⇒ lft | rgt)||HiRec||90/100 Gold||5/5||4.5/5||5/5||2015||3,199||discont.||check|
|Sony A7S II (⇒ lft | rgt)||Rec||-||4.5/5||5/5||5/5||2015||2,999||latest||check|
|Sony A7R (⇒ lft | rgt)||HiRec||82/100 Gold||4.5/5||5/5||5/5||2013||2,299||discont.||check|
|Sony A99 (⇒ lft | rgt)||-||84/100 Gold||4.5/5||reviewed||4.5/5||2012||2,799||discont.||check|
The above review scores should be interpreted with care, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, and comparing ratings of very distinct cameras or ones that are far apart in terms of their release date have little meaning. It should also be noted that some of the review sites have over time altered the way they render their verdicts.
In case you are interested in seeing how other cameras pair up, just make a corresponding selection in the search boxes below. There is also a set of direct links to comparison reviews that other users of the CAM-parator app explored. If you cannot find the camera you are interested in, please send me an email, and I will try to add information on that model to the database.
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