Nikon D810 vs Pentax 645D

The Nikon D810 and the Pentax 645D are two professional cameras that were announced, respectively, in June 2014 and March 2010. Both are DSLR (Digital Single Lens Reflex) cameras that are based on a full frame (D810) and a medium format (645D) sensor. The Nikon has a resolution of 36.2 megapixels, whereas the Pentax provides 39.5 MP.

Below is an overview of the main specs of the two cameras as a starting point for the comparison.

Headline Specifications

Nikon D810		Pentax 645D
Digital single lens reflex		Digital single lens reflex
Nikon F mount lenses		Pentax 645 mount lenses
36.2 MP – Full Frame sensor		39.5 MP – Medium Format sensor
1080/60p Video		no Video
ISO 64-12,800 (32 - 51,200)		ISO 100-1,600
Optical viewfinder		Optical viewfinder
3.2" LCD – 1229k dots		3.0" LCD – 921k dots
Fixed screen (not touch-sensitive)		Fixed screen (not touch-sensitive)
5 shutter flaps per second		1.1 shutter flaps per second
Weathersealed body		Weathersealed body
1200 shots per battery charge		800 shots per battery charge
146 x 123 x 82 mm, 980 g		156 x 117 x 119 mm, 1480 g

Check D810 offers at
ebay.com
Check 645D offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon D810 and the Pentax 645D? Which one should you buy? Read on to find out how these two cameras compare with respect to their body size, their imaging sensors, their shooting features, their input-output connections, and their reception by expert reviewers.

Body comparison

The physical size and weight of the Nikon D810 and the Pentax 645D are illustrated in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive perspectives from the front, the top, and the back are available. All width, height and depth dimensions are rounded to the nearest millimeter.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Pentax 645D is somewhat larger (2 percent) than the Nikon D810. Moreover, the 645D is substantially heavier (51 percent) than the D810. 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 and compare the specifications of available lenses in order to get the full picture of the size and weight of the two camera systems.

Concerning battery life, the D810 gets 1200 shots out of its Nikon EN-EL15 battery, while the 645D can take 800 images on a single charge of its Pentax D-LI90 power pack.

The following table provides a synthesis of the main physical specifications of the two cameras and other similar ones. In case you want to display and compare another camera duo, you can use the CAM-parator app to select your camera combination among a large number of options.

Body Specifications

		Camera Model	Camera Width	Camera Height	Camera Depth	Camera Weight	Battery Life	Weather Sealing	Camera Launch	Launch Price	Street Price
1.		Nikon D810	146 mm	123 mm	82 mm	980 g	1200	Y	Jun 2014	US$ 3 299	ebay.com
2.		Pentax 645D	156 mm	117 mm	119 mm	1480 g	800	Y	Mar 2010	US$ 9 995	ebay.com
3.		Canon 1D Mark IV	156 mm	157 mm	80 mm	1230 g	1500	Y	Oct 2009	US$ 4 999	ebay.com
4.		Canon 1D X	158 mm	168 mm	83 mm	1551 g	1120	Y	Oct 2011	US$ 6 799	ebay.com
5.		Canon 5DS	152 mm	116 mm	76 mm	930 g	700	Y	Feb 2015	US$ 3 699	ebay.com
6.		Leica S Typ 006	160 mm	120 mm	80 mm	1260 g	..	Y	Sep 2012	US$ 21 949	ebay.com
7.		Nikon D3S	160 mm	157 mm	88 mm	1240 g	4200	Y	Oct 2009	US$ 5 199	ebay.com
8.		Nikon D4S	160 mm	157 mm	91 mm	1350 g	3020	Y	Feb 2014	US$ 6 499	ebay.com
9.		Nikon D600	141 mm	113 mm	82 mm	850 g	900	Y	Sep 2012	US$ 2 099	ebay.com
10.		Nikon D610	141 mm	113 mm	82 mm	850 g	900	Y	Oct 2013	US$ 1 999	ebay.com
11.		Nikon D700	147 mm	123 mm	77 mm	1074 g	1000	Y	Jul 2008	US$ 2 999	ebay.com
12.		Nikon D750	141 mm	113 mm	78 mm	750 g	1230	Y	Sep 2014	US$ 2 299	ebay.com
13.		Nikon D800	146 mm	123 mm	82 mm	1000 g	900	Y	Feb 2012	US$ 2 999	ebay.com
14.		Nikon D800E	146 mm	123 mm	82 mm	1000 g	900	Y	Feb 2012	US$ 3 299	ebay.com
15.		Nikon D850	146 mm	124 mm	79 mm	1005 g	1840	Y	Jul 2017	US$ 3 299	amazon.com
16.		Nikon Df	144 mm	110 mm	67 mm	760 g	1400	Y	Nov 2013	US$ 2 749	ebay.com
17.		Pentax 645Z	156 mm	117 mm	123 mm	1550 g	650	Y	Apr 2014	US$ 8 499	ebay.com
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
Convert to Imperial

The price is, of course, an important factor in any camera decision. The manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The D810 was launched at a markedly lower price (by 67 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.

Sensor comparison

The imaging sensor is at the core of digital cameras and its size is one of the main determining factors of image quality. All other things equal, a large sensor will have larger individual pixel-units that offer better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixels in a sensor of the same technological generation. Further, a large sensor camera will give the photographer additional creative options when using shallow depth-of-field to isolate a subject from its 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 Nikon D810 features a full frame sensor and the Pentax 645D a medium format sensor. The sensor area in the 645D is 68 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.0 and 0.79. The sensor in the D810 has a native 3:2 aspect ratio, while the one in the 645D offers a 4:3 aspect.

With 39.5MP, the 645D offers a higher resolution than the D810 (36.2MP), but the 645D nevertheless has larger individual pixels (pixel pitch of 6.06μm versus 4.88μm for the D810) due to its larger sensor. However, the D810 is a much more recent model (by 4 years and 3 months) than the 645D, and its sensor will have benefitted from technological advances during this time that enhance the light gathering capacity of its pixel-units. 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.

The Nikon D810 has a native sensitivity range from ISO 64 to ISO 12800, which can be extended to ISO 32-51200. The corresponding ISO settings for the Pentax 645D are ISO 100 to ISO 1600 (no boost).

In terms of underlying technology, the D810 is build around a CMOS sensor, while the 645D uses a CCD imager. Both cameras use a Bayer filter for capturing RGB colors on a square grid of photosensors. This arrangement is found in most digital cameras.

Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. This service determines an overall sensor rating, as well as sub-scores for low-light sensitivity ("DXO Sports"), dynamic range ("DXO Landscape"), and color depth ("DXO Portrait"). Of the two cameras under review, the D810 provides substantially higher image quality than the 645D, with an overall score that is 15 points higher. This advantage is based on 1.1 bits higher color depth, 2.2 EV in additional dynamic range, and 1.2 stops in additional low light sensitivity. The adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Nikon D810	Full Frame	36.2	7360	4912	1080/60p	25.7	14.8	2853	97
2.		Pentax 645D	Medium Format	39.5	7264	5440	none	24.6	12.6	1262	82
3.		Canon 1D Mark IV	APS-H	16.0	4896	3264	1080/30p	22.8	12.0	1320	74
4.		Canon 1D X	Full Frame	17.9	5184	3456	1080/30p	23.8	11.8	2786	82
5.		Canon 5DS	Full Frame	50.3	8688	5792	1080/30p	24.7	12.4	2381	87
6.		Leica S Typ 006	Medium Format	37.5	7500	5000	none	23.9	12.2	824	76
7.		Nikon D3S	Full Frame	12.1	4256	2832	720/24p	23.5	12.0	3253	82
8.		Nikon D4S	Full Frame	16.2	4928	3280	1080/60p	24.4	13.3	3074	89
9.		Nikon D600	Full Frame	24.2	6016	4016	1080/30p	25.1	14.2	2980	94
10.		Nikon D610	Full Frame	24.2	6016	4016	1080/30p	25.1	14.4	2925	94
11.		Nikon D700	Full Frame	12.1	4256	2832	none	23.5	12.2	2303	80
12.		Nikon D750	Full Frame	24.2	6016	4016	1080/60p	24.8	14.5	2956	93
13.		Nikon D800	Full Frame	36.2	7360	4912	1080/30p	25.3	14.4	2853	95
14.		Nikon D800E	Full Frame	36.2	7360	4912	1080/30p	25.6	14.3	2979	96
15.		Nikon D850	Full Frame	45.4	8256	5504	4K/30p	26.4	14.8	2660	100
16.		Nikon Df	Full Frame	16.2	4928	3280	none	24.6	13.1	3279	89
17.		Pentax 645Z	Medium Format	51.1	8256	6192	1080/60i	26.0	14.7	4505	101

Many modern cameras are not only capable of taking still images, but also of capturing video footage. The D810 indeed provides movie recording capabilities, while the 645D does not. The highest resolution format that the D810 can use is 1080/60p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. The D810 and the 645D are similar in the sense that both have an optical viewfinder. The latter is useful for getting a clear image for framing even in brightly lit environments. The viewfinder in the D810 offers a wider field of view (100%) than the one in the 645D (98%), so that a larger proportion of the captured image is visible in the finder. On the other hand, the viewfinder of the 645D has a higher magnification (0.78x vs 0.70x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The following table reports on some other key feature differences and similarities of the Nikon D810, the Pentax 645D, and comparable cameras.

Core Features

		Camera Model	Viewfinder (Type or 000 dots)	Control Panel (yes/no)	LCD Specifications (inch/000 dots)	LCD Attach- ment	Touch Screen (yes/no)	Max Shutter Speed *	Max Shutter Flaps *	Built-in Flash (yes/no)	Built-in Image Stab
1.		Nikon D810	optical	Y	3.2 / 1229	fixed	n	1/8000s	5.0/s	Y	n
2.		Pentax 645D	optical	Y	3.0 / 921	fixed	n	1/4000s	1.1/s	n	n
3.		Canon 1D Mark IV	optical	Y	3.0 / 920	fixed	n	1/8000s	10.0/s	n	n
4.		Canon 1D X	optical	Y	3.2 / 1040	fixed	n	1/8000s	14.0/s	n	n
5.		Canon 5DS	optical	Y	3.2 / 1040	fixed	n	1/8000s	5.0/s	n	n
6.		Leica S Typ 006	optical	Y	3.0 / 922	fixed	n	1/4000s	1.5/s	n	n
7.		Nikon D3S	optical	Y	3.0 / 921	fixed	n	1/8000s	11.0/s	n	n
8.		Nikon D4S	optical	Y	3.2 / 921	fixed	n	1/8000s	11.0/s	n	n
9.		Nikon D600	optical	Y	3.0 / 921	fixed	n	1/4000s	5.5/s	Y	n
10.		Nikon D610	optical	Y	3.2 / 921	fixed	n	1/4000s	6.0/s	Y	n
11.		Nikon D700	optical	Y	3.0 / 922	fixed	n	1/8000s	8.0/s	Y	n
12.		Nikon D750	optical	Y	3.2 / 1229	tilting	n	1/4000s	6.0/s	Y	n
13.		Nikon D800	optical	Y	3.2 / 921	fixed	n	1/8000s	4.0/s	Y	n
14.		Nikon D800E	optical	Y	3.2 / 921	fixed	n	1/8000s	4.0/s	Y	n
15.		Nikon D850	optical	Y	3.2 / 2359	tilting	Y	1/8000s	9.0/s	n	n
16.		Nikon Df	optical	Y	3.2 / 921	fixed	n	1/4000s	5.5/s	n	n
17.		Pentax 645Z	optical	Y	3.2 / 1037	tilting	n	1/4000s	3.0/s	n	n
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One difference between the cameras concerns the presence of an on-board flash. The D810 has one, while the 645D does not. While the built-in flash of the D810 is not very powerful, it can at times be useful as a fill-in light.

The Nikon D810 and the Pentax 645D both have an intervalometer built-in. This enables the photographer to capture time lapse sequences, such as flower blooming, a sunset or moon rise, without purchasing an external camera trigger and related software.

The D810 writes its imaging data to Compact Flash or SDXC cards, while the 645D uses SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. The D810 supports UHS-I cards (Ultra High Speed data transfer of up to 104 MB/s), while the 645D cannot take advantage of Ultra High Speed SD cards.

Connectivity comparison

For some imaging applications, the extent to which a camera can communicate with its environment can be an important aspect in the camera decision process. The table below provides an overview of the connectivity of the Nikon D810 and Pentax 645D and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

Input-Output Connections

		Camera Model	Hotshoe Port	Internal Mic / Speaker	Microphone Port	Headphone Port	HDMI Port	USB Port	WiFi Support	NFC Support	Bluetooth Support
1.		Nikon D810	Y	stereo / mono	Y	Y	mini	3.0	Y	-	-
2.		Pentax 645D	Y	stereo / -	-	-	-	2.0	-	-	-
3.		Canon 1D Mark IV	Y	stereo / -	Y	-	mini	2.0	-	-	-
4.		Canon 1D X	Y	mono / -	Y	-	mini	2.0	-	-	-
5.		Canon 5DS	Y	mono / mono	Y	-	mini	3.0	-	-	-
6.		Leica S Typ 006	Y	- / -	-	-	mini	2.0	-	-	-
7.		Nikon D3S	Y	stereo / -	-	-	mini	2.0	-	-	-
8.		Nikon D4S	Y	mono / mono	Y	Y	mini	2.0	-	-	-
9.		Nikon D600	Y	mono / mono	Y	Y	mini	2.0	-	-	-
10.		Nikon D610	Y	mono / mono	Y	Y	mini	2.0	-	-	-
11.		Nikon D700	Y	- / -	-	-	mini	2.0	-	-	-
12.		Nikon D750	Y	stereo / mono	Y	Y	mini	2.0	Y	-	-
13.		Nikon D800	Y	mono / mono	Y	Y	mini	3.0	-	-	-
14.		Nikon D800E	Y	mono / mono	Y	Y	mini	3.0	-	-	-
15.		Nikon D850	Y	stereo / mono	Y	Y	mini	3.0	Y	Y	Y
16.		Nikon Df	Y	- / -	-	-	mini	2.0	-	-	-
17.		Pentax 645Z	Y	stereo / mono	Y	-	mini	3.0	-	-	-

It is notable that the D810 offers wifi support, while the 645D does not. Wifi can be a very convenient means to transfer image data to an off-camera location.

Both cameras feature a PC Sync terminal to control professional strobe lights, which will be appreciated by studio photographers.

Both the D810 and the 645D have been discontinued, but can regularly be found used on ebay. The 645D was replaced by the Pentax 645Z, while the D810 was followed by the Nikon D850. Further information on the features and operation of the D810 and 645D can be found, respectively, in the Nikon D810 Manual (free pdf) or the online Pentax 645D Manual.

Review summary

So what conclusions can be drawn? Is there a clear favorite between the Nikon D810 and the Pentax 645D? Which camera is better? Below is a summary of the relative strengths of each of the two contestants.

Reasons to prefer the Nikon D810:

• Better image quality: Scores substantially higher (15 points) in the DXO overall assessment.
• Richer colors: Generates images with noticeably better colors (1.1 bits more color depth).
• More dynamic range: Captures a larger spectrum of light and dark details (2.2 EV of extra DR).
• Better low-light sensitivity: Requires less light for good images (1.2 stops ISO advantage).
• Broader imaging potential: Can record not only still images but also 1080/60p movies.
• More complete view: Has a viewfinder with a larger field of view (100% vs 98%).
• Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
• More detailed LCD: Has a higher resolution rear screen (1229k vs 921k dots).
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (5 vs 1.1 flaps/sec) to capture the decisive moment.
• Less heavy: Is lighter (by 500g or 34 percent) and hence easier to carry around.
• Longer lasting: Can take more shots (1200 versus 800) on a single battery charge.
• Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
• Faster data transfer: Supports a more advanced USB protocol (3.0 vs 2.0).
• Easier file upload: Has wifi built in for automatic backup or image transfer to the web.
• Faster buffer clearing: Has an SD card interface that supports the UHS-I standard.
• More affordable: Was introduced into a lower priced category (67 percent cheaper at launch).
• More modern: Reflects 4 years and 3 months of technical progress since the 645D launch.

Arguments in favor of the Pentax 645D:

• Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x vs 0.70x).
• More heavily discounted: Has been around for much longer (launched in March 2010).

If the count of relative strengths (bullet points above) is taken as a measure, the D810 is the clear winner of the match-up (18 : 2 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 before making a camera decision. A professional wildlife photographer will view the differences between cameras in a way that diverges from the perspective of a family photog, and a person interested in architecture has distinct needs from a sports shooter. Hence, the decision which camera is best and worth buying is often a very personal one.

How about other alternatives? Do the specifications of the Nikon D810 and the Pentax 645D place the cameras among the top in their class? Find out in the latest Best DSLR Camera listing whether the two cameras rank among the cream of the crop.

In any case, while the comparison of technical specifications can provide a useful overview of the capabilities of different cameras, it remains incomplete and does no justice, for example, to the way the D810 or the 645D perform in practice. User reviews, such as those found at amazon, can sometimes inform about these issues, but such feedback is often incomplete, inconsistent, and biased.

Expert reviews

This is why hands-on reviews by experts are important. The following table reports the overall ratings of the cameras as published by some of the major camera review sites (amateurphotographer [AP], cameralabs [CL], digitalcameraworld [DCW], dpreview [DPR], ephotozine [EPZ], photographyblog [PB]). As can be seen, the professional reviewers agree in many cases on the quality of different cameras, but sometimes their assessments diverge, reinforcing the earlier point that a camera decision is often a very personal choice.

Expert Camera Reviews

		Camera   Model	AP   score	CL   score	DCW   score	DPR   score	EPZ   score	PB   score	Camera Launch	Launch Price	Street Price
1.		Nikon D810	5/5	..	5/5	86/100	5/5	4.5/5	Jun 2014	US$ 3 299	ebay.com
2.		Pentax 645D	5/5	..	..	..	..	..	Mar 2010	US$ 9 995	ebay.com
3.		Canon 1D Mark IV	5/5	..	..	89/100	..	..	Oct 2009	US$ 4 999	ebay.com
4.		Canon 1D X	5/5	..	..	..	4.5/5	4.5/5	Oct 2011	US$ 6 799	ebay.com
5.		Canon 5DS	..	+	..	83/100	4.5/5	4.5/5	Feb 2015	US$ 3 699	ebay.com
6.		Leica S Typ 006	..	..	..	..	..	..	Sep 2012	US$ 21 949	ebay.com
7.		Nikon D3S	5/5	..	..	89/100	4.5/5	5/5	Oct 2009	US$ 5 199	ebay.com
8.		Nikon D4S	5/5	..	..	..	4.5/5	4.5/5	Feb 2014	US$ 6 499	ebay.com
9.		Nikon D600	4/5	+ +	..	87/100	5/5	4.5/5	Sep 2012	US$ 2 099	ebay.com
10.		Nikon D610	4/5	+ +	..	87/100	4.5/5	4.5/5	Oct 2013	US$ 1 999	ebay.com
11.		Nikon D700	..	89/100	..	+ +	4.5/5	4.5/5	Jul 2008	US$ 2 999	ebay.com
12.		Nikon D750	5/5	+ +	4/5	90/100	4.5/5	4.5/5	Sep 2014	US$ 2 299	ebay.com
13.		Nikon D800	5/5	+ +	..	82/100	5/5	5/5	Feb 2012	US$ 2 999	ebay.com
14.		Nikon D800E	..	..	..	84/100	5/5	5/5	Feb 2012	US$ 3 299	ebay.com
15.		Nikon D850	4.5/5	+ +	5/5	89/100	4.5/5	5/5	Jul 2017	US$ 3 299	amazon.com
16.		Nikon Df	4/5	..	..	81/100	4/5	4/5	Nov 2013	US$ 2 749	ebay.com
17.		Pentax 645Z	5/5	..	3.5/5	..	4.5/5	5/5	Apr 2014	US$ 8 499	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The review scores listed above should be treated with care, though. The assessments were made in relation to similar cameras of the same technological generation. A score, therefore, has to be seen in close connection to the price and market introduction time of the camera, and comparisons of ratings among very different cameras or across long time periods have little meaning. It should also be noted that some of the review sites have over time altered the way they render their verdicts.

Check D810 offers at
ebay.com
Check 645D offers at
ebay.com

Other camera comparisons

Did this review help to inform your camera decision process? In case you are interested in seeing how other cameras pair up, just make your choice using the following search menu. As an alternative, you can also directly jump to any one of the listed comparisons that were previously generated by the CAM-parator tool.

~

Check D810 offers at
ebay.com
Check 645D offers at
ebay.com

Did you notice an error on this page? If so, please get in touch, so that we can correct the information.