Pentax K-1 II vs Sony A99 II

The Pentax K-1 II and the Sony Alpha ALT-A99 II are two digital cameras that were revealed to the public, respectively, in February 2018 and September 2016. Both are DSLR (Digital Single Lens Reflex) cameras that are equipped with a full frame sensor. The Pentax has a resolution of 36.2 megapixels, whereas the Sony provides 42.2 MP.

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

Headline Specifications

Pentax K-1 II		Sony A99 II
Digital single lens reflex		Digital single lens reflex
Pentax K mount lenses		Sony A mount lenses
36.2 MP – Full Frame sensor		42.2 MP – Full Frame sensor
1080/60i Video		4K/30p Video
ISO 100-819,200		ISO 100-25,600
Optical viewfinder		Electronic viewfinder (2400k dots)
3.2" LCD – 1037k dots		3.0" LCD – 1229k dots
Fully flexible screen (no touchscreen)		Fully flexible screen (no touchscreen)
4.4 shutter flaps per second		12 shutter flaps per second
In-body stabilization		In-body stabilization
Weathersealed body		Weathersealed body
670 shots per battery charge		490 shots per battery charge
137 x 110 x 86 mm, 1010 g		143 x 104 x 76 mm, 849 g

Check K-1 II price at
amazon.com
Check A99 II offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-1 II and the Sony Alpha ALT-A99 II? 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 side-by-side display below illustrates the physical size and weight of the Pentax K-1 II and the Sony A99 II. 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-1 II can be obtained in two different colors (black, silver), while the A99 II 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 II is somewhat smaller (1 percent) than the Pentax K-1 II. Moreover, the A99 II is markedly lighter (16 percent) than the K-1 II. 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-1 II gets 670 shots out of its Pentax D-LI90 battery, while the A99 II can take 490 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 would like to visualize and compare a different camera combination, you can navigate to the CAM-parator app and make your selection from a broad list of cameras there.

Body Specifications

		Camera Model	Camera Width	Camera Height	Camera Depth	Camera Weight	Battery Life	Weather Sealing	Camera Launch	Launch Price	Street Price
1.		Pentax K-1 II	137 mm	110 mm	86 mm	1010 g	670	Y	Feb 2018	US$ 1 999	amazon.com
2.		Sony A99 II	143 mm	104 mm	76 mm	849 g	490	Y	Sep 2016	US$ 3 199	ebay.com
3.		Canon 5DS R	152 mm	116 mm	76 mm	930 g	700	Y	Feb 2015	US$ 3 699	ebay.com
4.		Canon R	139 mm	98 mm	84 mm	660 g	370	Y	Sep 2018	US$ 2 299	ebay.com
5.		Nikon D850	146 mm	124 mm	79 mm	1005 g	1840	Y	Jul 2017	US$ 3 299	amazon.com
6.		Nikon Z6	134 mm	101 mm	67 mm	675 g	310	Y	Aug 2018	US$ 1 999	ebay.com
7.		Panasonic S1	149 mm	110 mm	97 mm	1017 g	400	Y	Feb 2019	US$ 2 499	amazon.com
8.		Panasonic S1H	151 mm	114 mm	110 mm	1052 g	400	Y	May 2019	US$ 3 999	amazon.com
9.		Panasonic S1R	149 mm	110 mm	97 mm	1016 g	380	Y	Feb 2019	US$ 3 699	amazon.com
10.		Pentax K-1	137 mm	110 mm	86 mm	1010 g	760	Y	Feb 2016	US$ 1 799	ebay.com
11.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	US$ 1 999	amazon.com
12.		Sony A7R II	127 mm	96 mm	60 mm	625 g	290	Y	Jun 2015	US$ 3 199	ebay.com
13.		Sony A7R III	127 mm	96 mm	74 mm	650 g	650	Y	Oct 2017	US$ 3 199	ebay.com
14.		Sony A7R IIIA	127 mm	96 mm	74 mm	650 g	650	Y	Apr 2021	US$ 3 199	amazon.com
15.		Sony A7S II	127 mm	96 mm	60 mm	627 g	370	Y	Sep 2015	US$ 2 999	ebay.com
16.		Sony A850	156 mm	117 mm	82 mm	895 g	880	Y	Aug 2009	US$ 1 999	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

Any camera decision will naturally be influenced heavily by the price. 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-1 II was launched at a markedly lower price (by 38 percent) than the A99 II, 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 size of the imaging sensor is a crucial determinant 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. 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.

Both cameras under consideration feature a full frame sensor and have a format factor (sometimes also referred to as "crop factor") of 1.0. Within the spectrum of camera sensors, this places the review cameras among the large-sensor cameras that aim for top notch image quality. 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 A99 II offers a higher resolution of 42.2 megapixels, compared with 36.2 MP of the K-1 II. This megapixels advantage translates into a 8 percent gain in linear resolution. On the other hand, these sensor specs imply that the A99 II has a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 4.52μm versus 4.88μm for the K-1 II). Moreover, it should be noted, that the K-1 II is a somewhat more recent model (by 1 year and 5 months) than the A99 II, and its sensor might have benefitted from technological advances during this time that further enhance the light gathering capacity of individual pixels. 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 Sony A99 II implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A99 II for good quality output (200 dots per inch) amounts to 39.8 x 26.5 inches or 101 x 67.4 cm, for very good quality (250 dpi) 31.8 x 21.2 inches or 80.8 x 53.9 cm, and for excellent quality (300 dpi) 26.5 x 17.7 inches or 67.3 x 44.9 cm. The corresponding values for the Pentax K-1 II are 36.8 x 24.6 inches or 93.5 x 62.4 cm for good quality, 29.4 x 19.6 inches or 74.8 x 49.9 cm for very good quality, and 24.5 x 16.4 inches or 62.3 x 41.6 cm for excellent quality prints.

The A99 II has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

Unlike the A99 II, the K-1 II 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-1 II has a native sensitivity range from ISO 100 to ISO 819200. The corresponding ISO settings for the Sony Alpha ALT-A99 II are ISO 100 to ISO 25600, with the possibility to increase the ISO range to 50-25600.

In terms of underlying technology, the K-1 II is build around a CMOS sensor, while the A99 II uses a BSI-CMOS 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.

For many cameras, data on sensor performance has been reported by DXO Mark. This service is based on lab testing and assigns an overall score to each camera sensor, as well as ratings for dynamic range ("DXO Landscape"), color depth ("DXO Portrait"), and low-light sensitivity ("DXO Sports"). 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-1 II	Full Frame	36.2	7360	4912	1080/60i	25.1	14.0	2698	93
2.		Sony A99 II	Full Frame	42.2	7952	5304	4K/30p	25.4	13.4	2317	92
3.		Canon 5DS R	Full Frame	50.3	8688	5792	1080/30p	24.6	12.4	2308	86
4.		Canon R	Full Frame	30.1	6720	4480	4K/30p	24.5	13.5	2742	89
5.		Nikon D850	Full Frame	45.4	8256	5504	4K/30p	26.4	14.8	2660	100
6.		Nikon Z6	Full Frame	24.3	6048	4024	4K/30p	25.3	14.3	3299	95
7.		Panasonic S1	Full Frame	24.0	6000	4000	4K/60p	25.2	14.5	3333	95
8.		Panasonic S1H	Full Frame	24.0	6000	4000	6K/30p	25.2	14.2	2805	94
9.		Panasonic S1R	Full Frame	46.7	8368	5584	4K/60p	26.4	14.1	3525	100
10.		Pentax K-1	Full Frame	36.2	7360	4912	1080/60i	25.4	14.6	3280	96
11.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
12.		Sony A7R II	Full Frame	42.2	7952	5304	4K/30p	26.0	13.9	3434	98
13.		Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
14.		Sony A7R IIIA	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
15.		Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85
16.		Sony A850	Full Frame	24.4	6048	4032	none	23.8	12.2	1415	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 can also record movies. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the A99 II provides a better video resolution than the K-1 II. It can shoot movie footage at 4K/30p, while the Pentax is limited to 1080/60i.

Feature comparison

Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A99 II has an electronic viewfinder (2400k dots), while the K-1 II 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 II has a higher magnification than the one of the K-1 II (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 adjacent table lists some of the other core features of the Pentax K-1 II and Sony A99 II 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.		Pentax K-1 II	optical	Y	3.2 / 1037	full-flex	n	1/8000s	4.4/s	n	Y
2.		Sony A99 II	2400	Y	3.0 / 1229	full-flex	n	1/8000s	12.0/s	n	Y
3.		Canon 5DS R	optical	Y	3.2 / 1040	fixed	n	1/8000s	5.0/s	n	n
4.		Canon R	3690	Y	3.2 / 2100	swivel	Y	1/8000s	8.0/s	n	n
5.		Nikon D850	optical	Y	3.2 / 2359	tilting	Y	1/8000s	9.0/s	n	n
6.		Nikon Z6	3690	Y	3.2 / 2100	tilting	Y	1/8000s	12.0/s	n	Y
7.		Panasonic S1	5760	Y	3.2 / 2100	full-flex	Y	1/8000s	9.0/s	n	Y
8.		Panasonic S1H	5760	Y	3.2 / 2330	swivel	Y	1/8000s	9.0/s	n	Y
9.		Panasonic S1R	5760	Y	3.2 / 2100	full-flex	Y	1/8000s	9.0/s	n	Y
10.		Pentax K-1	optical	Y	3.2 / 1037	full-flex	n	1/8000s	4.4/s	n	Y
11.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
12.		Sony A7R II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
13.		Sony A7R III	3686	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
14.		Sony A7R IIIA	3686	n	3.0 / 2340	tilting	Y	1/8000s	10.0/s	n	Y
15.		Sony A7S II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
16.		Sony A850	optical	Y	3.0 / 922	fixed	n	1/8000s	3.0/s	n	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

The Pentax K-1 II 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-1 II writes its imaging data to SDXC cards, while the A99 II uses SDXC or Memory Stick PRO Duo cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. 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-1 II and Sony Alpha ALT-A99 II 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-1 II	Y	stereo / mono	Y	Y	micro	2.0	Y	-	-
2.		Sony A99 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	Y
3.		Canon 5DS R	Y	mono / mono	Y	-	mini	3.0	-	-	-
4.		Canon R	Y	stereo / mono	Y	Y	mini	3.1	Y	-	Y
5.		Nikon D850	Y	stereo / mono	Y	Y	mini	3.0	Y	Y	Y
6.		Nikon Z6	Y	stereo / mono	Y	Y	micro	3.1	Y	-	Y
7.		Panasonic S1	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
8.		Panasonic S1H	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
9.		Panasonic S1R	Y	stereo / mono	Y	Y	full	3.1	Y	-	Y
10.		Pentax K-1	Y	stereo / mono	Y	Y	micro	2.0	Y	-	-
11.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
12.		Sony A7R II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
13.		Sony A7R III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
14.		Sony A7R IIIA	Y	stereo / mono	Y	Y	micro	3.2	Y	Y	Y
15.		Sony A7S II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
16.		Sony A850	Y	- / -	-	-	mini	2.0	-	-	-

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

Travel and landscape photographers will find it useful that the K-1 II has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.

The K-1 II is a recent model that features in the current product line-up of Pentax. In contrast, the A99 II has been discontinued (but can be found pre-owned on ebay). There has not been a direct replacement model for the A99 II from Sony. Further information on the features and operation of the K-1 II and A99 II can be found, respectively, in the Pentax K-1 II Manual (free pdf) or the online Sony A99 II Manual.

Review summary

So what is the bottom line? Is the Pentax K-1 II better than the Sony A99 II or vice versa? A synthesis of the relative strong points of each of the models is listed below.

Arguments in favor of the Pentax K-1 II:

• High quality composites: Can combine several shots after pixel-shifting its sensor.
• Brighter framing: Features an optical viewfinder for clear, lag-free composition.
• Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• Longer lasting: Can take more shots (670 versus 490) on a single battery charge.
• Easier geotagging: Features an internal GPS sensor to log localization data.
• More affordable: Was introduced into a lower priced category (38 percent cheaper at launch).
• More modern: Is somewhat more recent (announced 1 year and 5 months after the A99 II).

Advantages of the Sony Alpha ALT-A99 II:

• More detail: Has more megapixels (42.2 vs 36.2MP), which boosts linear resolution by 8%.
• Better video: Provides higher definition movie capture (4K/30p vs 1080/60i).
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• More framing info: Has an electronic viewfinder that displays shooting data.
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x vs 0.70x).
• More detailed LCD: Has a higher resolution rear screen (1229k vs 1037k dots).
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster burst: Shoots at higher frequency (12 vs 4.4 flaps/sec) to capture the decisive moment.
• Less heavy: Has a lower weight (by 161g or 16 percent) and is thus easier to take along.
• Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
• Easier wireless transfer: Supports Bluetooth for image sharing without cables.
• More heavily discounted: Has been on the market for longer (launched in September 2016).

If the count of relative strengths (bullet points above) is taken as a measure, the A99 II is the clear winner of the contest (12 : 8 points). However, the relative importance of the various individual camera aspects will vary according to personal preferences and needs, so that you might like to apply corresponding weights to the particular features before making a decision on a new camera. 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 Pentax K-1 II and the Sony A99 II 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 K-1 II or the A99 II 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 where reviews by experts come in. 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	Street Price
1.		Pentax K-1 II	..	..	4.5/5	79/100	4.5/5	4.5/5	Feb 2018	US$ 1 999	amazon.com
2.		Sony A99 II	..	..	4.5/5	85/100	4.5/5	4.5/5	Sep 2016	US$ 3 199	ebay.com
3.		Canon 5DS R	5/5	+	..	83/100	5/5	4.5/5	Feb 2015	US$ 3 699	ebay.com
4.		Canon R	4/5	o	4/5	79/100	4.5/5	4/5	Sep 2018	US$ 2 299	ebay.com
5.		Nikon D850	4.5/5	+ +	5/5	89/100	4.5/5	5/5	Jul 2017	US$ 3 299	amazon.com
6.		Nikon Z6	5/5	..	5/5	89/100	4.5/5	5/5	Aug 2018	US$ 1 999	ebay.com
7.		Panasonic S1	4.5/5	+ +	4.5/5	88/100	4.5/5	4/5	Feb 2019	US$ 2 499	amazon.com
8.		Panasonic S1H	..	..	4/5	90/100	..	..	May 2019	US$ 3 999	amazon.com
9.		Panasonic S1R	4.5/5	..	4.6/5	89/100	4.5/5	4.5/5	Feb 2019	US$ 3 699	amazon.com
10.		Pentax K-1	5/5	..	..	84/100	5/5	5/5	Feb 2016	US$ 1 799	ebay.com
11.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	US$ 1 999	amazon.com
12.		Sony A7R II	5/5	+ +	5/5	90/100	5/5	5/5	Jun 2015	US$ 3 199	ebay.com
13.		Sony A7R III	..	+ +	4/5	90/100	4.5/5	5/5	Oct 2017	US$ 3 199	ebay.com
14.		Sony A7R IIIA	..	+ +	4/5	90/100	4.5/5	5/5	Apr 2021	US$ 3 199	amazon.com
15.		Sony A7S II	5/5	+	..	..	4.5/5	5/5	Sep 2015	US$ 2 999	ebay.com
16.		Sony A850	3/5	..	..	75/100	..	4.5/5	Aug 2009	US$ 1 999	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. Also, please note that some of the review sites have changed their methodology and reporting over time.

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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. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.

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