Pentax K-70 vs Sony A99

The Pentax K-70 and the Sony Alpha SLT-A99 are two digital cameras that were announced, respectively, in June 2016 and September 2012. Both are DSLR (Digital Single Lens Reflex) cameras that are based on an APS-C (K-70) and a full frame (A99) sensor. Both cameras offer a resolution of 24 megapixels.

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

Headline Specifications

Pentax K-70		Sony A99
Digital single lens reflex		Digital single lens reflex
Pentax K mount lenses		Sony A mount lenses
24 MP – APS-C sensor		24 MP – Full Frame sensor
1080/60i Video		1080/60p Video
ISO 100-102,400		ISO 100-25,600
Optical viewfinder		Electronic viewfinder (2359k dots)
3.0" LCD – 921k dots		3.0" LCD – 1229k dots
Swivel screen (not touch-sensitive)		Fully flexible screen (no touchscreen)
6 shutter flaps per second		6 shutter flaps per second
In-body stabilization		In-body stabilization
Weathersealed body		Weathersealed body
410 shots per battery charge		500 shots per battery charge
126 x 93 x 74 mm, 688 g		147 x 111 x 78 mm, 812 g

Check K-70 offers at
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Check A99 offers at
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Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-70 and the Sony Alpha SLT-A99? 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 Pentax K-70 and the Sony A99 is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All width, height and depth measures are rounded to the nearest millimeter.

The K-70 can be obtained in two different colors (black, silver), while the A99 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 Sony A99 is notably larger (39 percent) than the Pentax K-70. Moreover, the A99 is markedly heavier (18 percent) than the K-70. 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 K-70 gets 410 shots out of its Pentax D-LI109 battery, while the A99 can take 500 images on a single charge of its Sony NP-FM500H power pack.

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, 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.		Pentax K-70	126 mm	93 mm	74 mm	688 g	410	Y	Jun 2016	649	ebay.com
2.		Sony A99	147 mm	111 mm	78 mm	812 g	500	Y	Sep 2012	2,799	ebay.com
3.		Pentax K-3 III	135 mm	104 mm	74 mm	820 g	800	Y	Mar 2021	1,999	amazon.com
4.		Pentax KP	132 mm	101 mm	76 mm	703 g	390	Y	Jan 2017	1,099	ebay.com
5.		Pentax K-S2	123 mm	91 mm	73 mm	678 g	410	Y	Feb 2015	749	ebay.com
6.		Pentax K-3 II	131 mm	100 mm	77 mm	800 g	720	Y	Apr 2015	1,099	ebay.com
7.		Pentax K-S1	121 mm	93 mm	70 mm	558 g	410	n	Aug 2014	749	ebay.com
8.		Pentax K-50	130 mm	97 mm	71 mm	650 g	410	Y	Jun 2013	599	ebay.com
9.		Pentax K-500	130 mm	97 mm	71 mm	646 g	710	n	Jun 2013	549	ebay.com
10.		Pentax K-3	131 mm	100 mm	77 mm	800 g	560	Y	Oct 2013	1,299	ebay.com
11.		Pentax K-5	131 mm	97 mm	73 mm	760 g	740	Y	Sep 2010	1,099	ebay.com
12.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	4,499	amazon.com
13.		Sony A99 II	143 mm	104 mm	76 mm	849 g	490	Y	Sep 2016	3,199	ebay.com
14.		Sony A68	143 mm	104 mm	81 mm	610 g	540	n	Nov 2015	699	ebay.com
15.		Sony A77	143 mm	104 mm	81 mm	732 g	470	Y	Aug 2011	1,399	ebay.com
16.		Sony A850	156 mm	117 mm	82 mm	895 g	880	Y	Aug 2009	1,999	ebay.com
17.		Sony A900	156 mm	117 mm	82 mm	895 g	880	Y	Sep 2008	2,999	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 retail prices at the time of the camera’s release place the model in the market relative to other models in the producer’s line-up and the competition. The K-70 was launched at a markedly lower price (by 77 percent) than the A99, 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.

Sensor comparison

The size of the imaging sensor is a crucial determinant of image quality. A large sensor will tend to have larger individual pixels that provide better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixel-units 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 are more costly to manufacture and tend to lead to bigger and heavier cameras and lenses.

Of the two cameras under consideration, the Pentax K-70 features an APS-C sensor and the Sony A99 a full frame sensor. The sensor area in the A99 is 132 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.5 and 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

Even though the A99 has a larger sensor, both cameras offer the same resolution of 24 megapixels. This implies that the A99 has a lower pixel density and larger individual pixels (with a pixel pitch of 5.96μm versus 3.91μm for the K-70), which gives it a potential advantage in terms of light gathering capacity. It should, however, be noted that the K-70 is much more recent (by 3 years and 8 months) than the A99, and its sensor will have benefitted from technological advances during this time that at least partly 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 K-70 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

Unlike the A99, 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 Pentax K-70 has a native sensitivity range from ISO 100 to ISO 102400. The corresponding ISO settings for the Sony Alpha SLT-A99 are ISO 100 to ISO 25600, with the possibility to increase the ISO range to 50-25600.

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.

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"). 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.		Pentax K-70	APS-C	24.0	6000	4000	1080/60i	23.8	13.1	1639	80
2.		Sony A99	Full Frame	24.0	6000	4000	1080/60p	25.0	14.0	1555	89
3.		Pentax K-3 III	APS-C	25.6	6192	4128	4K/30p	24.2	13.7	2083	85
4.		Pentax KP	APS-C	24.1	6016	4000	1080/60i	23.9	13.2	1699	81
5.		Pentax K-S2	APS-C	20.0	5472	3648	1080/30p	23.6	12.9	1514	79
6.		Pentax K-3 II	APS-C	24.1	6016	4000	1080/60i	23.6	13.6	1106	80
7.		Pentax K-S1	APS-C	20.0	5472	3648	1080/30p	23.5	13.0	1061	78
8.		Pentax K-50	APS-C	16.1	4928	3264	1080/30p	23.7	13.0	1120	79
9.		Pentax K-500	APS-C	16.1	4928	3264	1080/30p	23.7	13.1	1087	79
10.		Pentax K-3	APS-C	24.1	6016	4000	1080/60i	23.7	13.4	1216	80
11.		Pentax K-5	APS-C	16.1	4928	3264	1080/25p	23.7	14.1	1162	82
12.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
13.		Sony A99 II	Full Frame	42.2	7952	5304	4K/30p	25.4	13.4	2317	92
14.		Sony A68	APS-C	24.0	6000	4000	1080/60i	24.1	13.5	701	79
15.		Sony A77	APS-C	24.0	6000	4000	1080/60p	24.0	13.2	801	78
16.		Sony A850	Full Frame	24.4	6048	4032	none	23.8	12.2	1415	79
17.		Sony A900	Full Frame	24.4	6048	4032	none	23.7	12.3	1431	79
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. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the A99 provides a faster frame rate than the K-70. It can shoot movie footage at 1080/60p, while the Pentax is limited to 1080/60i.

Feature comparison

Apart from body and sensor, cameras can and do differ across a range of features. For example, the A99 has an electronic viewfinder (2359k 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 A99 has a higher magnification than the one of the K-70 (0.71x vs 0.63x), 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 Pentax K-70, the Sony A99, 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.		Pentax K-70	optical	n	3.0 / 921	swivel	n	1/6000s	6.0/s	Y	Y
2.		Sony A99	2359	Y	3.0 / 1229	full-flex	n	1/8000s	6.0/s	n	Y
3.		Pentax K-3 III	optical	Y	3.2 / 1620	fixed	Y	1/8000s	12.0/s	n	Y
4.		Pentax KP	optical	n	3.0 / 921	tilting	n	1/6000s	7.0/s	Y	Y
5.		Pentax K-S2	optical	n	3.0 / 921	swivel	n	1/6000s	5.4/s	Y	Y
6.		Pentax K-3 II	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	n	Y
7.		Pentax K-S1	optical	n	3.0 / 921	fixed	n	1/6000s	5.4/s	Y	Y
8.		Pentax K-50	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
9.		Pentax K-500	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
10.		Pentax K-3	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	Y	Y
11.		Pentax K-5	optical	Y	3.0 / 921	fixed	n	1/8000s	7.0/s	Y	Y
12.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
13.		Sony A99 II	2400	Y	3.0 / 1229	full-flex	n	1/8000s	12.0/s	n	Y
14.		Sony A68	1440	Y	2.7 / 460	tilting	n	1/4000s	8.0/s	Y	Y
15.		Sony A77	2359	Y	3.0 / 921	full-flex	n	1/8000s	12.0/s	Y	Y
16.		Sony A850	optical	Y	3.0 / 922	fixed	n	1/8000s	3.0/s	n	Y
17.		Sony A900	optical	Y	3.0 / 922	fixed	n	1/8000s	5.0/s	n	Y
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 K-70 has one, while the A99 does not. While the built-in flash of the K-70 is not very powerful, it can at times be useful as a fill-in light.

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 K-70 writes its imaging data to SDXC cards, while the A99 uses SDXC or Memory Stick PRO Duo cards. The A99 features dual card slots, which can be very useful in case a memory card fails. In contrast, the K-70 only has one slot. Both cameras can use UHS-I cards, which provide for Ultra High Speed data transfer of up to 104 MB/s.

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 Pentax K-70 and Sony Alpha SLT-A99 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.		Pentax K-70	Y	stereo / mono	Y	-	mini	2.0	Y	-	-
2.		Sony A99	Y	stereo / mono	Y	Y	mini	2.0	-	-	-
3.		Pentax K-3 III	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
4.		Pentax KP	Y	stereo / mono	Y	-	-	2.0	Y	-	-
5.		Pentax K-S2	Y	mono / mono	Y	-	micro	2.0	Y	Y	-
6.		Pentax K-3 II	Y	mono / mono	Y	Y	mini	3.0	-	-	-
7.		Pentax K-S1	Y	stereo / mono	-	-	micro	2.0	-	-	-
8.		Pentax K-50	Y	mono / mono	-	-	micro	2.0	-	-	-
9.		Pentax K-500	Y	mono / mono	-	-	-	2.0	-	-	-
10.		Pentax K-3	Y	mono / mono	Y	Y	mini	3.0	-	-	-
11.		Pentax K-5	Y	stereo / mono	Y	-	mini	2.0	-	-	-
12.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
13.		Sony A99 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	Y
14.		Sony A68	Y	stereo / mono	Y	-	micro	2.0	-	-	-
15.		Sony A77	Y	stereo / mono	Y	-	mini	2.0	-	-	-
16.		Sony A850	Y	- / -	-	-	mini	2.0	-	-	-
17.		Sony A900	Y	- / -	-	-	mini	2.0	-	-	-

It is notable that the K-70 offers wifi support, while the A99 does not. Wifi can be a very convenient means to transfer image data to an off-camera location.

Studio photographers will appreciate that the Sony A99 (unlike the K-70) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Travel and landscape photographers will find it useful that the A99 has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.

Both the K-70 and the A99 have been discontinued, but can regularly be found used on ebay. The A99 was replaced by the Sony A99, while the K-70 does not have a direct successor. Further information on the features and operation of the K-70 and A99 can be found, respectively, in the Pentax K-70 Manual (free pdf) or the online Sony A99 Manual.

Review summary

So how do things add up? Which of the two cameras – the Pentax K-70 or the Sony A99 – has the upper hand? Is one clearly better than the other? Below is a summary of the relative strengths of each of the two contestants.

Arguments in favor of the Pentax K-70:

• 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.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• More compact: Is smaller (126x93mm vs 147x111mm) and thus needs less room in the bag.
• Less heavy: Is lighter (by 124g or 15 percent) and hence easier to carry around.
• 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.
• More affordable: Was introduced into a lower priced category (77 percent cheaper at launch).
• More modern: Reflects 3 years and 8 months of technical progress since the A99 launch.

Reasons to prefer the Sony Alpha SLT-A99:

• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• Better video: Provides higher movie framerates (1080/60p versus 1080/60i).
• Better sound control: Has a headphone port that enables audio monitoring while recording.
• More framing info: Has an electronic viewfinder that displays shooting data.
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.71x vs 0.63x).
• Easier setting verification: Features a control panel on top to check shooting parameters.
• More detailed LCD: Has a higher resolution rear screen (1229k vs 921k dots).
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/6000s) to freeze action.
• Longer lasting: Gets more shots (500 versus 410) out of a single battery charge.
• Easier geotagging: Features an internal GPS sensor to log localization data.
• 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 September 2012).

If the count of relative strengths (bullet points above) is taken as a measure, the A99 emerges as the winner of the match-up (13 : 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 wedding photographer will view the differences between cameras in a way that diverges from the perspective of a travel photog, and a person interested in cityscapes has distinct needs from a macro 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 Pentax K-70 and the Sony A99 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 the spec-sheets of cameras can offer a general idea of their imaging potential, it remains incomplete and does no justice, for example, to the way the K-70 or the A99 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 expert reviews 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 (USD)	Street Price
1.		Pentax K-70	4.5/5	..	4/5	79/100	4.5/5	4.5/5	Jun 2016	649	ebay.com
2.		Sony A99	5/5	..	..	84/100	4.5/5	4.5/5	Sep 2012	2,799	ebay.com
3.		Pentax K-3 III	4/5	..	3/5	..	4.5/5	..	Mar 2021	1,999	amazon.com
4.		Pentax KP	4/5	..	3/5	82/100	5/5	4.5/5	Jan 2017	1,099	ebay.com
5.		Pentax K-S2	4.5/5	..	..	..	5/5	4.5/5	Feb 2015	749	ebay.com
6.		Pentax K-3 II	4.5/5	..	..	..	5/5	5/5	Apr 2015	1,099	ebay.com
7.		Pentax K-S1	4/5	..	..	..	4.5/5	4/5	Aug 2014	749	ebay.com
8.		Pentax K-50	5/5	..	..	..	5/5	4.5/5	Jun 2013	599	ebay.com
9.		Pentax K-500	..	..	..	..	4.5/5	4.5/5	Jun 2013	549	ebay.com
10.		Pentax K-3	4/5	..	..	83/100	5/5	5/5	Oct 2013	1,299	ebay.com
11.		Pentax K-5	4/5	..	..	83/100	5/5	4.5/5	Sep 2010	1,099	ebay.com
12.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	4,499	amazon.com
13.		Sony A99 II	..	..	4.5/5	85/100	4.5/5	4.5/5	Sep 2016	3,199	ebay.com
14.		Sony A68	3/5	..	..	..	4/5	4/5	Nov 2015	699	ebay.com
15.		Sony A77	5/5	91/100	..	81/100	..	5/5	Aug 2011	1,399	ebay.com
16.		Sony A850	3/5	..	..	75/100	..	4.5/5	Aug 2009	1,999	ebay.com
17.		Sony A900	..	+ +	..	+ +	4.5/5	5/5	Sep 2008	2,999	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The above review scores should be interpreted 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 rating-comparisons among cameras that span long time periods or concern very differently equipped models make little sense. It should also be noted that some of the review sites have over time altered the way they render their verdicts.

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Other camera comparisons

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