Canon SX620 vs Pentax 645D

The Canon PowerShot SX620 HS and the Pentax 645D are two digital cameras that were announced, respectively, in May 2016 and March 2010. The SX620 is a fixed lens compact, while the 645D is a DSLR. The cameras are based on a 1/2.3-inch (SX620) and a medium format (645D) sensor. The Canon has a resolution of 20.2 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

Canon SX620		Pentax 645D
Fixed lens compact camera		Digital single lens reflex
25-625mm f/3.2-6.6		Pentax 645 mount lenses
20.2 MP – 1/2.3" sensor		39.5 MP – Medium Format sensor
1080/30p Video		no Video
ISO 80-3,200		ISO 100-1,600
No viewfinder, LCD framing		Optical viewfinder
3.0" LCD – 922k dots		3.0" LCD – 921k dots
Fixed screen (not touch-sensitive)		Fixed screen (not touch-sensitive)
2.5 shutter flaps per second		1.1 shutter flaps per second
not weather sealed		Weathersealed body
295 shots per battery charge		800 shots per battery charge
97 x 57 x 28 mm, 182 g		156 x 117 x 119 mm, 1480 g

Check SX620 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 Canon PowerShot SX620 HS 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

An illustration of the physical size and weight of the Canon SX620 and the Pentax 645D is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive views from the front, the top, and the rear side are shown. All width, height and depth measures are rounded to the nearest millimeter.

The SX620 can be obtained in three different colors (black, silver, red), while the 645D is only available in black.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Pentax 645D is considerably larger (230 percent) than the Canon SX620. It is noteworthy in this context that the 645D is splash and dust-proof, while the SX620 does not feature any corresponding weather-sealing.

The above size and weight comparisons are to some extent incomplete and possibly misleading, as the SX620 has a lens built in, whereas the 645D is an interchangeable lens camera that requires a separate lens. Attaching the latter will add extra weight and bulk to the setup.

Concerning battery life, the SX620 gets 295 shots out of its Canon NB-13L 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 (USD)	Street Price
1.		Canon SX620	97 mm	57 mm	28 mm	182 g	295	n	May 2016	279	ebay.com
2.		Pentax 645D	156 mm	117 mm	119 mm	1480 g	800	Y	Mar 2010	9,995	ebay.com
3.		Canon SX430	104 mm	69 mm	85 mm	323 g	195	n	Jan 2017	299	ebay.com
4.		Canon G9 X Mark II	98 mm	58 mm	31 mm	206 g	235	n	Jan 2017	529	ebay.com
5.		Canon SX730	110 mm	64 mm	40 mm	300 g	250	n	Apr 2017	399	ebay.com
6.		Canon SX420	104 mm	69 mm	85 mm	325 g	195	n	Jan 2016	299	ebay.com
7.		Canon SX540	120 mm	82 mm	92 mm	442 g	205	n	Jan 2016	399	ebay.com
8.		Canon SX720	110 mm	64 mm	36 mm	270 g	250	n	Feb 2016	379	ebay.com
9.		Canon G9 X	98 mm	58 mm	31 mm	209 g	220	n	Oct 2015	529	ebay.com
10.		Canon SX410	104 mm	69 mm	85 mm	325 g	185	n	Feb 2015	279	ebay.com
11.		Canon SX610	105 mm	61 mm	27 mm	191 g	270	n	Jan 2015	249	ebay.com
12.		Canon SX710	113 mm	66 mm	35 mm	269 g	230	n	Jan 2015	349	ebay.com
13.		Canon 1D X	158 mm	168 mm	83 mm	1551 g	1120	Y	Oct 2011	6,799	ebay.com
14.		Canon 1D Mark IV	156 mm	157 mm	80 mm	1230 g	1500	Y	Oct 2009	4,999	ebay.com
15.		Leica S Typ 006	160 mm	120 mm	80 mm	1260 g	..	Y	Sep 2012	21,950	ebay.com
16.		Nikon D3S	160 mm	157 mm	88 mm	1240 g	4200	Y	Oct 2009	5,199	ebay.com
17.		Pentax 645Z	156 mm	117 mm	123 mm	1550 g	650	Y	Apr 2014	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 listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The SX620 was launched at a lower price than the 645D, despite having a lens built in. Normally, street prices remain initially close to the MSRP, but after a couple of months, the first discounts appear. 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. Furthermore, a large sensor camera will give the photographer more possibilities to use shallow depth-of-field in order to isolate a subject from the background. On the downside, larger sensors tend to be associated with larger, more expensive camera bodies and lenses.

Of the two cameras under consideration, the Canon SX620 features a 1/2.3-inch sensor and the Pentax 645D a medium format sensor. The sensor area in the 645D is 5086 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 5.6 and 0.79. Both cameras feature a native aspect ratio (sensor width to sensor height) of 4:3.

With 39.5MP, the 645D offers a higher resolution than the SX620 (20.2MP), but the 645D nevertheless has larger individual pixels (pixel pitch of 6.06μm versus 1.18μm for the SX620) due to its larger sensor. However, the SX620 is a much more recent model (by 6 years and 2 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 resolution advantage of the Pentax 645D implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the 645D for good quality output (200 dots per inch) amounts to 36.3 x 27.2 inches or 92.3 x 69.1 cm, for very good quality (250 dpi) 29.1 x 21.8 inches or 73.8 x 55.3 cm, and for excellent quality (300 dpi) 24.2 x 18.1 inches or 61.5 x 46.1 cm. The corresponding values for the Canon SX620 are 25.9 x 19.4 inches or 65.8 x 49.4 cm for good quality, 20.7 x 15.6 inches or 52.7 x 39.5 cm for very good quality, and 17.3 x 13 inches or 43.9 x 32.9 cm for excellent quality prints.

The Canon PowerShot SX620 HS has a native sensitivity range from ISO 80 to ISO 3200. The corresponding ISO settings for the Pentax 645D are ISO 100 to ISO 1600 (no boost).

In terms of underlying technology, the SX620 is build around a BSI-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.

Consistent information on actual sensor performance is available from DXO Mark for many cameras. 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"). 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.		Canon SX620	1/2.3	20.2	5184	3888	1080/30p	20.4	11.8	838	49
2.		Pentax 645D	Medium Format	39.5	7264	5440	none	24.6	12.6	1262	82
3.		Canon SX430	1/2.3	19.9	5152	3864	720/25p	20.5	11.9	900	49
4.		Canon G9 X Mark II	1-inch	20.0	5472	3648	1080/60p	21.9	12.5	522	65
5.		Canon SX730	1/2.3	20.2	5184	3888	1080/60p	20.5	11.9	924	50
6.		Canon SX420	1/2.3	19.9	5152	3864	720/25p	20.3	11.7	806	48
7.		Canon SX540	1/2.3	20.2	5184	3888	1080/60p	20.3	11.7	806	48
8.		Canon SX720	1/2.3	20.2	5184	3888	1080/60p	20.3	11.8	817	48
9.		Canon G9 X	1-inch	20.0	5472	3648	1080/60p	21.5	12.3	495	63
10.		Canon SX410	1/2.3	19.9	5152	3864	720/30p	20.2	11.6	720	47
11.		Canon SX610	1/2.3	20.2	5184	3888	1080/30p	20.2	11.6	712	47
12.		Canon SX710	1/2.3	20.2	5184	3888	1080/60p	20.2	11.6	712	47
13.		Canon 1D X	Full Frame	17.9	5184	3456	1080/30p	23.8	11.8	2786	82
14.		Canon 1D Mark IV	APS-H	16.0	4896	3264	1080/30p	22.8	12.0	1320	74
15.		Leica S Typ 006	Medium Format	37.5	7500	5000	none	23.9	12.2	824	76
16.		Nikon D3S	Full Frame	12.1	4256	2832	720/24p	23.5	12.0	3253	82
17.		Pentax 645Z	Medium Format	51.1	8256	6192	1080/60i	26.0	14.7	4505	101
Note: DXO values in italics represent estimates based on sensor size and age.

Many modern cameras are not only capable of taking still images, but also of capturing video footage. The SX620 indeed provides movie recording capabilities, while the 645D does not. The highest resolution format that the SX620 can use is 1080/30p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the 645D has an optical viewfinder, which can be very useful when shooting in bright sunlight. In contrast, the SX620 relies on live view and the rear LCD for framing. The following table reports on some other key feature differences and similarities of the Canon SX620, 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.		Canon SX620	none	n	3.0 / 922	fixed	n	1/2000s	2.5/s	Y	Y
2.		Pentax 645D	optical	Y	3.0 / 921	fixed	n	1/4000s	1.1/s	n	n
3.		Canon SX430	none	n	3.0 / 230	fixed	n	1/4000s	0.5/s	Y	Y
4.		Canon G9 X Mark II	none	n	3.0 / 1040	fixed	Y	1/2000s	8.2/s	Y	Y
5.		Canon SX730	none	n	3.0 / 922	tilting	n	1/3200s	5.9/s	Y	Y
6.		Canon SX420	none	n	3.0 / 230	fixed	n	1/4000s	0.5/s	Y	Y
7.		Canon SX540	none	n	3.0 / 461	fixed	n	1/2000s	5.9/s	Y	Y
8.		Canon SX720	none	n	3.0 / 922	fixed	n	1/3200s	5.9/s	Y	Y
9.		Canon G9 X	none	n	3.0 / 1040	fixed	Y	1/2000s	6.0/s	Y	Y
10.		Canon SX410	none	n	3.0 / 230	fixed	n	1/4000s	0.5/s	Y	Y
11.		Canon SX610	none	n	3.0 / 922	fixed	n	1/2000s	2.5/s	Y	Y
12.		Canon SX710	none	n	3.0 / 922	fixed	n	1/3200s	6.0/s	Y	Y
13.		Canon 1D X	optical	Y	3.2 / 1040	fixed	n	1/8000s	14.0/s	n	n
14.		Canon 1D Mark IV	optical	Y	3.0 / 920	fixed	n	1/8000s	10.0/s	n	n
15.		Leica S Typ 006	optical	Y	3.0 / 922	fixed	n	1/4000s	1.5/s	n	n
16.		Nikon D3S	optical	Y	3.0 / 921	fixed	n	1/8000s	11.0/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 SX620 has one, while the 645D does not. While the built-in flash of the SX620 is not very powerful, it can at times be useful as a fill-in light.

The Pentax 645D has 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.

Concerning the storage of imaging data, both the SX620 and the 645D write their files to SDXC cards. The 645D features dual card slots, which can be very useful in case a memory card fails. In contrast, the SX620 only has one slot.

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 Canon PowerShot SX620 HS 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.		Canon SX620	-	mono / mono	-	-	micro	2.0	Y	Y	-
2.		Pentax 645D	Y	stereo / -	-	-	-	2.0	-	-	-
3.		Canon SX430	-	mono / mono	-	-	-	2.0	Y	Y	-
4.		Canon G9 X Mark II	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
5.		Canon SX730	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
6.		Canon SX420	-	mono / mono	-	-	-	2.0	Y	Y	-
7.		Canon SX540	-	stereo / mono	-	-	mini	2.0	Y	Y	-
8.		Canon SX720	-	stereo / mono	-	-	micro	2.0	Y	Y	-
9.		Canon G9 X	-	stereo / mono	-	-	micro	2.0	Y	Y	-
10.		Canon SX410	-	stereo / mono	-	-	-	2.0	-	-	-
11.		Canon SX610	-	- / -	-	-	micro	2.0	Y	Y	-
12.		Canon SX710	-	stereo / mono	-	-	micro	2.0	Y	Y	-
13.		Canon 1D X	Y	mono / -	Y	-	mini	2.0	-	-	-
14.		Canon 1D Mark IV	Y	stereo / -	Y	-	mini	2.0	-	-	-
15.		Leica S Typ 006	Y	- / -	-	-	mini	2.0	-	-	-
16.		Nikon D3S	Y	stereo / -	-	-	mini	2.0	-	-	-
17.		Pentax 645Z	Y	stereo / mono	Y	-	mini	3.0	-	-	-

It is notable that the SX620 offers wifi support, while the 645D does not. Wifi can be a very convenient means to transfer image data to an off-camera location.

Studio photographers will appreciate that the Pentax 645D (unlike the SX620) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Both the SX620 and the 645D have been discontinued, but can regularly be found used on ebay. The 645D was replaced by the Pentax 645Z, while the SX620 does not have a direct successor. Further information on the features and operation of the SX620 and 645D can be found, respectively, in the Canon SX620 Manual (free pdf) or the online Pentax 645D Manual.

Review summary

So what conclusions can be drawn? Is there a clear favorite between the Canon SX620 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 Canon PowerShot SX620 HS:

• Broader imaging potential: Can record not only still images but also 1080/30p movies.
• Faster burst: Shoots at higher frequency (2.5 vs 1.1 flaps/sec) to capture the decisive moment.
• Ready to shoot: Comes with a built-in lens, while the 645D requires a separate lens.
• More compact: Is smaller (97x57mm vs 156x117mm) and thus needs less room in the bag.
• Less heavy: Is lighter even though it comes with a built-in lens (unlike the 645D).
• Sharper images: Has hand-shake reducing image stabilization built-in.
• Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
• Easier file upload: Has wifi built in for automatic backup or image transfer to the web.
• Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
• More affordable: Was introduced at a lower price, despite coming with a built-in lens.
• More modern: Reflects 6 years and 2 months of technical progress since the 645D launch.

Arguments in favor of the Pentax 645D:

• More detail: Has more megapixels (39.5 vs 20.2MP), which boosts linear resolution by 40%.
• Better image quality: Features bigger pixels on a larger sensor for higher quality imaging.
• Richer colors: The pixel size advantage translates into images with better, more accurate colors.
• More dynamic range: Larger pixels capture a wider spectrum of light and dark details.
• Better low-light sensitivity: Larger pixels means good image quality even under poor lighting.
• Easier framing: Has an optical viewfinder for image composition and settings control.
• Easier setting verification: Features a control panel on top to check shooting parameters.
• Faster shutter: Has higher mechanical shutter speed (1/4000s vs 1/2000s) to freeze action.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• More flexible: Makes it possible to change lenses and thus to use specialty optics.
• Longer lasting: Gets more shots (800 versus 295) out of a single battery charge.
• Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
• Better lighting: Features a hotshoe and can thus hold and trigger an external flash gun.
• Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
• Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
• More heavily discounted: Has been around for much longer (launched in March 2010).

If the number of relative strengths (bullet points above) is taken as a guide, the 645D is the clear winner of the contest (16 : 11 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 Canon SX620 and the Pentax 645D place the cameras among the top in their class? Find out in the latest Best Superzoom Camera and Best DSLR Camera listings 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 SX620 or the 645D perform in practice. At times, user reviews, such as those published at amazon, address these issues in a useful manner, but such feedback is on many occasions incomplete, inconsistent, and unreliable.

Expert reviews

This is why hands-on reviews by experts are important. The adjacent summary-table relays the overall verdicts of several of the most popular 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 (USD)	Street Price
1.		Canon SX620	..	..	..	..	..	4/5	May 2016	279	ebay.com
2.		Pentax 645D	5/5	..	..	..	..	..	Mar 2010	9,995	ebay.com
3.		Canon SX430	..	..	..	..	3.5/5	3.5/5	Jan 2017	299	ebay.com
4.		Canon G9 X Mark II	4/5	..	4/5	75/100	4.5/5	4.5/5	Jan 2017	529	ebay.com
5.		Canon SX730	..	+	..	..	4/5	4/5	Apr 2017	399	ebay.com
6.		Canon SX420	..	..	..	..	..	3/5	Jan 2016	299	ebay.com
7.		Canon SX540	..	..	..	..	..	..	Jan 2016	399	ebay.com
8.		Canon SX720	..	+	..	..	4/5	4.5/5	Feb 2016	379	ebay.com
9.		Canon G9 X	3.5/5	+ +	..	..	4.5/5	4.5/5	Oct 2015	529	ebay.com
10.		Canon SX410	..	o	..	..	..	..	Feb 2015	279	ebay.com
11.		Canon SX610	..	..	..	..	4/5	4/5	Jan 2015	249	ebay.com
12.		Canon SX710	..	+	..	..	4/5	3.5/5	Jan 2015	349	ebay.com
13.		Canon 1D X	5/5	..	..	..	4.5/5	4.5/5	Oct 2011	6,799	ebay.com
14.		Canon 1D Mark IV	5/5	..	..	89/100	..	..	Oct 2009	4,999	ebay.com
15.		Leica S Typ 006	..	..	..	..	..	..	Sep 2012	21,950	ebay.com
16.		Nikon D3S	5/5	..	..	89/100	4.5/5	5/5	Oct 2009	5,199	ebay.com
17.		Pentax 645Z	5/5	..	3.5/5	..	4.5/5	5/5	Apr 2014	8,499	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The review scores listed above should be treated with care, though. The ratings are only valid when referring to cameras in the same category and of the same age. 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 SX620 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 SX620 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.