Sony A58 vs Pentax K-70

The Sony Alpha SLT-A58 and the Pentax K-70 are two digital cameras that were revealed to the public, respectively, in February 2013 and June 2016. Both are DSLR (Digital Single Lens Reflex) cameras that are equipped with an APS-C sensor. The Sony has a resolution of 19.8 megapixels, whereas the Pentax provides 24 MP.

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

Headline Specifications

Sony A58		Pentax K-70
Digital single lens reflex		Digital single lens reflex
Sony A mount lenses		Pentax K mount lenses
19.8 MP – APS-C sensor		24 MP – APS-C sensor
1080/60i Video		1080/60i Video
ISO 100-16,000 (100 - 25,600)		ISO 100-102,400
Electronic viewfinder (1440k dots)		Optical viewfinder
2.7" LCD – 460k dots		3.0" LCD – 921k dots
Tilting screen (no touchscreen)		Swivel screen (not touch-sensitive)
5 shutter flaps per second		6 shutter flaps per second
In-body stabilization		In-body stabilization
not weather sealed		Weathersealed body
690 shots per battery charge		410 shots per battery charge
129 x 95 x 78 mm, 492 g		126 x 93 x 74 mm, 688 g

Check A58 offers at
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Check K-70 offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Sony Alpha SLT-A58 and the Pentax K-70? 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 Sony A58 and the Pentax K-70 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.

The K-70 can be obtained in two different colors (black, silver), while the A58 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 K-70 is somewhat smaller (4 percent) than the Sony A58. However, the K-70 is substantially heavier (40 percent) than the A58. It is noteworthy in this context that the K-70 is splash and dust-proof, while the A58 does not feature any corresponding weather-sealing.

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 A58 gets 690 shots out of its Sony NP-FM500H battery, while the K-70 can take 410 images on a single charge of its Pentax D-LI109 power pack.

The adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. If you want to switch the focus of the display and review another camera pair, you can move across to the CAM-parator tool and choose from the broad selection of possible camera comparisons there.

Body Specifications

		Camera Model	Camera Width	Camera Height	Camera Depth	Camera Weight	Battery Life	Weather Sealing	Camera Launch	Launch Price (USD)	Street Price
1.		Sony A58	129 mm	95 mm	78 mm	492 g	690	n	Feb 2013	599	ebay.com
2.		Pentax K-70	126 mm	93 mm	74 mm	688 g	410	Y	Jun 2016	649	ebay.com
3.		Canon SL1	117 mm	91 mm	69 mm	407 g	380	n	Mar 2013	549	ebay.com
4.		Canon T5i	133 mm	100 mm	79 mm	580 g	440	n	Mar 2013	649	ebay.com
5.		Nikon D3200	125 mm	96 mm	77 mm	505 g	540	n	Apr 2012	599	ebay.com
6.		Nikon D3300	124 mm	98 mm	76 mm	430 g	700	n	Jan 2014	499	ebay.com
7.		Pentax K-3 II	131 mm	100 mm	77 mm	800 g	720	Y	Apr 2015	1,099	ebay.com
8.		Pentax K-3 III	135 mm	104 mm	74 mm	820 g	800	Y	Mar 2021	1,999	amazon.com
9.		Pentax K-50	130 mm	97 mm	71 mm	650 g	410	Y	Jun 2013	599	ebay.com
10.		Pentax KP	132 mm	101 mm	76 mm	703 g	390	Y	Jan 2017	1,099	ebay.com
11.		Pentax K-S1	121 mm	93 mm	70 mm	558 g	410	n	Aug 2014	749	ebay.com
12.		Pentax K-S2	123 mm	91 mm	73 mm	678 g	410	Y	Feb 2015	749	ebay.com
13.		Sony A68	143 mm	104 mm	81 mm	610 g	540	n	Nov 2015	699	ebay.com
14.		Sony A77 II	143 mm	104 mm	81 mm	647 g	480	Y	May 2014	1,199	ebay.com
15.		Sony A3000	128 mm	91 mm	85 mm	411 g	470	n	Aug 2013	329	ebay.com
16.		Sony A5100	110 mm	63 mm	36 mm	283 g	400	n	Aug 2014	549	ebay.com
17.		Sony A6000	120 mm	67 mm	45 mm	344 g	360	n	Feb 2014	599	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 A58 was somewhat cheaper (by 8 percent) than the K-70 at launch, but both cameras fall into the same price category. 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. 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.

Both cameras under consideration feature an APS-C sensor and have a format factor (sometimes also referred to as "crop factor") of 1.5. Within the spectrum of camera sensors, this places the review cameras among the medium-sized sensor cameras that aim to strike a balance between image quality and portability. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

While the two cameras under review share the same sensor size, the K-70 offers a higher resolution of 24 megapixels, compared with 19.8 MP of the A58. This megapixels advantage translates into a 10 percent gain in linear resolution. On the other hand, these sensor specs imply that the K-70 has a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 3.91μm versus 4.31μm for the A58). However, it should be noted that the K-70 is much more recent (by 3 years and 3 months) than the A58, and its sensor will have benefitted from technological advances during this time that compensate for the smaller pixel size. Coming back to sensor resolution, it should be mentioned that the K-70 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The resolution advantage of the Pentax K-70 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-70 for good quality output (200 dots per inch) amounts to 30 x 20 inches or 76.2 x 50.8 cm, for very good quality (250 dpi) 24 x 16 inches or 61 x 40.6 cm, and for excellent quality (300 dpi) 20 x 13.3 inches or 50.8 x 33.9 cm. The corresponding values for the Sony A58 are 27.3 x 18.2 inches or 69.3 x 46.1 cm for good quality, 21.8 x 14.5 inches or 55.4 x 36.9 cm for very good quality, and 18.2 x 12.1 inches or 46.2 x 30.8 cm for excellent quality prints.

The K-70 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

Unlike the A58, the K-70 has the capacity to capture high quality composite images by combining multiple shots after shifting its sensor by miniscule distances. This multi-shot, pixel-shift mode is most suitable for photography of stationary objects (landscapes, studio scenes).

The Sony Alpha SLT-A58 has a native sensitivity range from ISO 100 to ISO 16000, which can be extended to ISO 100-25600. The corresponding ISO settings for the Pentax K-70 are ISO 100 to ISO 102400 (no boost).

Technology-wise, both cameras are equipped with CMOS (Complementary Metal–Oxide–Semiconductor) sensors. Both cameras use a Bayer filter for capturing RGB colors on a square grid of photosensors. This arrangement is found in most digital cameras.

For many cameras, data on sensor performance has been reported by DXO Mark. 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. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Sony A58	APS-C	19.8	5456	3632	1080/60i	23.3	12.5	753	74
2.		Pentax K-70	APS-C	24.0	6000	4000	1080/60i	23.8	13.1	1639	80
3.		Canon SL1	APS-C	17.9	5184	3456	1080/30p	21.8	11.3	843	63
4.		Canon T5i	APS-C	17.9	5184	3456	1080/30p	21.7	11.2	681	61
5.		Nikon D3200	APS-C	24.1	6016	4000	1080/30p	24.1	13.2	1131	81
6.		Nikon D3300	APS-C	24.0	6000	4000	1080/60p	24.3	12.8	1385	82
7.		Pentax K-3 II	APS-C	24.1	6016	4000	1080/60i	23.6	13.6	1106	80
8.		Pentax K-3 III	APS-C	25.6	6192	4128	4K/30p	24.2	13.7	2083	85
9.		Pentax K-50	APS-C	16.1	4928	3264	1080/30p	23.7	13.0	1120	79
10.		Pentax KP	APS-C	24.1	6016	4000	1080/60i	23.9	13.2	1699	81
11.		Pentax K-S1	APS-C	20.0	5472	3648	1080/30p	23.5	13.0	1061	78
12.		Pentax K-S2	APS-C	20.0	5472	3648	1080/30p	23.6	12.9	1514	79
13.		Sony A68	APS-C	24.0	6000	4000	1080/60i	24.1	13.5	701	79
14.		Sony A77 II	APS-C	24.0	6000	4000	1080/60p	24.4	13.4	1013	82
15.		Sony A3000	APS-C	19.8	5456	3632	1080/60i	23.7	12.8	1068	78
16.		Sony A5100	APS-C	24.0	6000	4000	1080/60p	23.8	12.7	1347	80
17.		Sony A6000	APS-C	24.0	6000	4000	1080/60p	24.1	13.1	1347	82
Note: DXO values in italics represent estimates based on sensor size and age.

Many modern cameras cannot only take still pictures, but also record videos. The two cameras under consideration both have sensors whose read-out speed is fast enough to capture moving pictures, and both provide the same movie specifications (1080/60i).

Feature comparison

Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A58 has an electronic viewfinder (1440k dots), while the K-70 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 viewfinders of both cameras offer the same field of view (100%), but the viewfinder of the K-70 has a higher magnification than the one of the A58 (0.63x vs 0.57x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The adjacent table lists some of the other core features of the Sony A58 and Pentax K-70 along with similar information for a selection of comparators.

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.		Sony A58	1440	n	2.7 / 460	tilting	n	1/4000s	5.0/s	Y	Y
2.		Pentax K-70	optical	n	3.0 / 921	swivel	n	1/6000s	6.0/s	Y	Y
3.		Canon SL1	optical	n	3.0 / 1040	fixed	Y	1/4000s	4.9/s	Y	n
4.		Canon T5i	optical	n	3.0 / 1040	swivel	Y	1/4000s	5.0/s	Y	n
5.		Nikon D3200	optical	n	3.0 / 921	fixed	n	1/4000s	4.0/s	Y	n
6.		Nikon D3300	optical	n	3.0 / 921	fixed	n	1/4000s	5.0/s	Y	n
7.		Pentax K-3 II	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	n	Y
8.		Pentax K-3 III	optical	Y	3.2 / 1620	fixed	Y	1/8000s	12.0/s	n	Y
9.		Pentax K-50	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
10.		Pentax KP	optical	n	3.0 / 921	tilting	n	1/6000s	7.0/s	Y	Y
11.		Pentax K-S1	optical	n	3.0 / 921	fixed	n	1/6000s	5.4/s	Y	Y
12.		Pentax K-S2	optical	n	3.0 / 921	swivel	n	1/6000s	5.4/s	Y	Y
13.		Sony A68	1440	Y	2.7 / 460	tilting	n	1/4000s	8.0/s	Y	Y
14.		Sony A77 II	2359	Y	3.0 / 1229	full-flex	n	1/8000s	12.0/s	Y	Y
15.		Sony A3000	202	n	3.0 / 230	fixed	n	1/4000s	2.5/s	Y	n
16.		Sony A5100	none	n	3.0 / 922	tilting	Y	1/4000s	6.0/s	Y	n
17.		Sony A6000	1440	n	3.0 / 922	tilting	n	1/4000s	11.0/s	Y	n
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

The Pentax K-70 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.

The A58 writes its imaging data to SDXC or Memory Stick PRO Duo cards, while the K-70 uses SDXC cards. The K-70 supports UHS-I cards (Ultra High Speed data transfer of up to 104 MB/s), while the A58 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 Sony Alpha SLT-A58 and Pentax K-70 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.		Sony A58	Y	stereo / mono	Y	-	mini	2.0	-	-	-
2.		Pentax K-70	Y	stereo / mono	Y	-	mini	2.0	Y	-	-
3.		Canon SL1	Y	mono / mono	Y	-	mini	2.0	-	-	-
4.		Canon T5i	Y	stereo / mono	Y	-	mini	2.0	-	-	-
5.		Nikon D3200	Y	mono / mono	Y	-	mini	2.0	-	-	-
6.		Nikon D3300	Y	mono / mono	Y	-	mini	2.0	-	-	-
7.		Pentax K-3 II	Y	mono / mono	Y	Y	mini	3.0	-	-	-
8.		Pentax K-3 III	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
9.		Pentax K-50	Y	mono / mono	-	-	micro	2.0	-	-	-
10.		Pentax KP	Y	stereo / mono	Y	-	-	2.0	Y	-	-
11.		Pentax K-S1	Y	stereo / mono	-	-	micro	2.0	-	-	-
12.		Pentax K-S2	Y	mono / mono	Y	-	micro	2.0	Y	Y	-
13.		Sony A68	Y	stereo / mono	Y	-	micro	2.0	-	-	-
14.		Sony A77 II	Y	stereo / mono	Y	-	mini	2.0	Y	Y	-
15.		Sony A3000	Y	stereo / mono	-	-	mini	2.0	-	-	-
16.		Sony A5100	-	stereo / mono	-	-	micro	2.0	Y	Y	-
17.		Sony A6000	Y	stereo / mono	-	-	micro	2.0	Y	Y	-

It is notable that the K-70 offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the A58 does not provide wifi capability.

Both the A58 and the K-70 have been discontinued, but can regularly be found used on ebay. The A58 was replaced by the Sony A68, while the K-70 does not have a direct successor. Further information on the features and operation of the A58 and K-70 can be found, respectively, in the Sony A58 Manual (free pdf) or the online Pentax K-70 Manual.

Review summary

So how do things add up? Is there a clear favorite between the Sony A58 and the Pentax K-70? Which camera is better? The listing below highlights the relative strengths of the two models.

Advantages of the Sony Alpha SLT-A58:

• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• More framing info: Has an electronic viewfinder that displays shooting data.
• Less heavy: Is lighter (by 196g or 28 percent) and hence easier to carry around.
• Longer lasting: Can take more shots (690 versus 410) on a single battery charge.
• More heavily discounted: Has been available for much longer (launched in February 2013).

Arguments in favor of the Pentax K-70:

• More detail: Has more megapixels (24 vs 19.8MP), which boosts linear resolution by 10%.
• Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
• High quality composites: Can combine several shots after pixel-shifting its sensor.
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• Brighter framing: Features an optical viewfinder for clear, lag-free composition.
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.63x vs 0.57x).
• Larger screen: Has a bigger rear LCD (3.0" vs 2.7") for image review and settings control.
• More detailed LCD: Has a higher resolution rear screen (921k vs 460k dots).
• More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster shutter: Has higher mechanical shutter speed (1/6000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (6 vs 5 flaps/sec) to capture the decisive moment.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
• 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 modern: Reflects 3 years and 3 months of technical progress since the A58 launch.

If the number of relative strengths (bullet points above) is taken as a guide, the K-70 is the clear winner of the contest (17 : 5 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 Sony A58 and the Pentax K-70 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 specs-based evaluation of cameras can be instructive in revealing their potential as photographic tools, it remains partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the A58 or the K-70. 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 where reviews by experts come in. The table below provides a synthesis of the camera assessments of some of the best known photo-gear 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.		Sony A58	3/5	..	..	..	4.5/5	4.5/5	Feb 2013	599	ebay.com
2.		Pentax K-70	4.5/5	..	4/5	79/100	4.5/5	4.5/5	Jun 2016	649	ebay.com
3.		Canon SL1	4/5	+	..	78/100	4/5	4/5	Mar 2013	549	ebay.com
4.		Canon T5i	..	..	..	76/100	4.5/5	4.5/5	Mar 2013	649	ebay.com
5.		Nikon D3200	5/5	+ +	..	73/100	4.5/5	4.5/5	Apr 2012	599	ebay.com
6.		Nikon D3300	3/5	+	..	77/100	4.5/5	4.5/5	Jan 2014	499	ebay.com
7.		Pentax K-3 II	4.5/5	..	..	..	5/5	5/5	Apr 2015	1,099	ebay.com
8.		Pentax K-3 III	4/5	..	3/5	..	4.5/5	..	Mar 2021	1,999	amazon.com
9.		Pentax K-50	5/5	..	..	..	5/5	4.5/5	Jun 2013	599	ebay.com
10.		Pentax KP	4/5	..	3/5	82/100	5/5	4.5/5	Jan 2017	1,099	ebay.com
11.		Pentax K-S1	4/5	..	..	..	4.5/5	4/5	Aug 2014	749	ebay.com
12.		Pentax K-S2	4.5/5	..	..	..	5/5	4.5/5	Feb 2015	749	ebay.com
13.		Sony A68	3/5	..	..	..	4/5	4/5	Nov 2015	699	ebay.com
14.		Sony A77 II	4/5	..	..	80/100	4.5/5	5/5	May 2014	1,199	ebay.com
15.		Sony A3000	3/5	+	..	..	4/5	4/5	Aug 2013	329	ebay.com
16.		Sony A5100	4.5/5	+	..	..	4.5/5	5/5	Aug 2014	549	ebay.com
17.		Sony A6000	5/5	+	4.5/5	80/100	4.5/5	5/5	Feb 2014	599	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Care should be taken when interpreting the review scores above, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. Hence, a score should always be seen in the context of the camera's market launch date and its price, and comparing ratings of very distinct cameras or ones that are far apart in terms of their release date have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

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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.

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