Sony HX99 vs A7 III

The Sony Cyber-shot DSC-HX99 and the Sony Alpha A7 III are two digital cameras that were revealed to the public, respectively, in August 2018 and February 2018. The HX99 is a fixed lens compact, while the A7 III is a mirrorless interchangeable lens camera. The cameras are based on a 1/2.3-inch (HX99) and a full frame (A7 III) sensor. The HX99 has a resolution of 18 megapixels, whereas the A7 III 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 HX99		Sony A7 III
Fixed lens compact camera		Mirrorless system camera
24-720mm f/3.5-6.4		Sony E mount lenses
18 MP – 1/2.3" sensor		24 MP – Full Frame sensor
4K/30p Video		4K/30p Video
ISO 80-3,200 (80 - 6,400)		ISO 100-51,200 (50 - 204,800)
Electronic viewfinder (638k dots)		Electronic viewfinder (2359k dots)
3.0" LCD – 922k dots		3.0" LCD – 922k dots
Tilting touchscreen		Tilting touchscreen
10 shutter flaps per second		10 shutter flaps per second
Lens-based stabilization		In-body stabilization
not weather sealed		Weathersealed body
370 shots per battery charge		610 shots per battery charge
102 x 58 x 36 mm, 242 g		127 x 96 x 74 mm, 650 g

Check HX99 offers at
ebay.com
Check A7 III price at
amazon.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Sony Cyber-shot DSC-HX99 and the Sony Alpha A7 III? 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 Sony HX99 and the Sony A7 III. 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 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 Sony A7 III is considerably larger (106 percent) than the Sony HX99. It is noteworthy in this context that the A7 III is splash and dust-proof, while the HX99 does not feature any corresponding weather-sealing.

The above size and weight comparisons are to some extent incomplete and possibly misleading, as the HX99 has a lens built in, whereas the A7 III is an interchangeable lens camera that requires a separate lens. Attaching the latter will add extra weight and bulk to the setup. You can compare the optics available for the A7 III and their specifications in the Sony FE Lens Catalog.

Concerning battery life, the HX99 gets 370 shots out of its Sony NP-BX1 battery, while the A7 III can take 610 images on a single charge of its Sony NP-FZ100 power pack. The battery packs of both cameras can be charged via USB, which can be very convenient when travelling.

The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. 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.		Sony HX99	102 mm	58 mm	36 mm	242 g	370	n	Aug 2018	449	ebay.com
2.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	1,999	amazon.com
3.		Canon SX70	127 mm	91 mm	117 mm	608 g	325	n	Sep 2018	549	amazon.com
4.		Canon SX730	110 mm	64 mm	40 mm	300 g	250	n	Apr 2017	399	ebay.com
5.		Canon SX740	110 mm	64 mm	40 mm	299 g	265	n	Jul 2018	399	amazon.com
6.		Nikon A1000	114 mm	72 mm	41 mm	330 g	250	n	Jan 2019	429	ebay.com
7.		Nikon W300	112 mm	66 mm	29 mm	231 g	280	Y	May 2017	389	ebay.com
8.		Nikon Z6	134 mm	101 mm	67 mm	675 g	310	Y	Aug 2018	1,999	ebay.com
9.		Panasonic ZS70	112 mm	67 mm	41 mm	322 g	380	n	Apr 2017	449	ebay.com
10.		Sony A7 II	127 mm	96 mm	60 mm	599 g	350	Y	Nov 2014	1,999	ebay.com
11.		Sony A7R III	127 mm	96 mm	74 mm	650 g	650	Y	Oct 2017	3,199	ebay.com
12.		Sony A7R IV	129 mm	96 mm	78 mm	665 g	670	Y	Jul 2019	3,499	ebay.com
13.		Sony A9	127 mm	96 mm	63 mm	673 g	650	Y	Apr 2017	4,499	ebay.com
14.		Sony HX90V	102 mm	58 mm	36 mm	245 g	360	n	Apr 2015	429	ebay.com
15.		Sony HX95	102 mm	58 mm	36 mm	242 g	370	n	Aug 2018	429	ebay.com
16.		Sony HX400V	130 mm	93 mm	103 mm	660 g	300	n	Feb 2014	499	ebay.com
17.		Sony WX800	102 mm	58 mm	36 mm	233 g	370	n	Oct 2018	399	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 obviously take relative prices into account. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The HX99 was launched at a lower price than the A7 III, despite having a lens built in. 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 sensor inside a digital camera is one of the key determinants 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. 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 are more costly to manufacture and tend to lead to bigger and heavier cameras and lenses.

Of the two cameras under consideration, the Sony HX99 features a 1/2.3-inch sensor and the Sony A7 III a full frame sensor. The sensor area in the A7 III is 2925 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 5.6 and 1.0. The sensor in the HX99 has a native 4:3 aspect ratio, while the one in the A7 III offers a 3:2 aspect.

With 24MP, the A7 III offers a higher resolution than the HX99 (18MP), but the A7 III nevertheless has larger individual pixels (pixel pitch of 5.94μm versus 1.25μm for the HX99) due to its larger sensor. However, the HX99 is a somewhat more recent model (by 6 months) than the A7 III, and its sensor might 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 the HX99 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The resolution advantage of the Sony A7 III implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A7 III 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 HX99 are 24.5 x 18.4 inches or 62.2 x 46.6 cm for good quality, 19.6 x 14.7 inches or 49.7 x 37.3 cm for very good quality, and 16.3 x 12.2 inches or 41.5 x 31.1 cm for excellent quality prints.

The A7 III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

The Sony Cyber-shot DSC-HX99 has a native sensitivity range from ISO 80 to ISO 3200, which can be extended to ISO 80-6400. The corresponding ISO settings for the Sony Alpha A7 III are ISO 100 to ISO 51200, with the possibility to increase the ISO range to 50-204800.

In terms of underlying technology, the HX99 is build around a CMOS sensor, while the A7 III 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.

Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. 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 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.		Sony HX99	1/2.3	18.0	4896	3672	4K/30p	20.6	12.1	1058	51
2.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
3.		Canon SX70	1/2.3	20.2	5184	3888	4K/30p	20.6	12.1	1063	51
4.		Canon SX730	1/2.3	20.2	5184	3888	1080/60p	20.5	11.9	924	50
5.		Canon SX740	1/2.3	20.2	5184	3888	4K/30p	20.6	12.1	1050	51
6.		Nikon A1000	1/2.3	15.9	4608	3456	4K/30p	20.7	12.2	1095	52
7.		Nikon W300	1/2.3	15.9	4608	3456	4K/30p	20.5	12.0	938	50
8.		Nikon Z6	Full Frame	24.3	6048	4024	4K/30p	25.3	14.3	3299	95
9.		Panasonic ZS70	1/2.3	20.2	5184	3888	4K/30p	19.1	10.6	106	36
10.		Sony A7 II	Full Frame	24.0	6000	4000	1080/60p	24.9	13.6	2449	90
11.		Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
12.		Sony A7R IV	Full Frame	60.2	9504	6336	4K/30p	26.0	14.8	3344	99
13.		Sony A9	Full Frame	24.0	6000	4000	4K/30p	24.9	13.3	3517	92
14.		Sony HX90V	1/2.3	18.0	4896	3672	1080/60p	20.2	11.6	738	47
15.		Sony HX95	1/2.3	18.0	4896	3672	4K/30p	20.6	12.1	1057	51
16.		Sony HX400V	1/2.3	20.2	5184	3888	1080/60p	20.1	11.4	629	45
17.		Sony WX800	1/2.3	18.0	4896	3672	4K/30p	20.6	12.2	1070	51
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. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, and both provide the same movie specifications (4K/30p).

Feature comparison

Apart from body and sensor, cameras can and do differ across a range of features. The two cameras under review are similar with respect to both having an electronic viewfinder. However, the one in the A7 III offers a substantially higher resolution than the one in the HX99 (2359k vs 638k dots). The adjacent table lists some of the other core features of the Sony HX99 and Sony A7 III 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 HX99	638	n	3.0 / 922	tilting	Y	1/2000s	10.0/s	Y	Y
2.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
3.		Canon SX70	2360	n	3.0 / 922	swivel	n	1/2000s	10.0/s	Y	Y
4.		Canon SX730	none	n	3.0 / 922	tilting	n	1/3200s	5.9/s	Y	Y
5.		Canon SX740	none	n	3.0 / 922	tilting	n	1/3200s	10.0/s	Y	Y
6.		Nikon A1000	1166	n	3.0 / 1036	tilting	Y	1/4000s	7.0/s	Y	Y
7.		Nikon W300	none	n	3.0 / 921	fixed	n	1/4000s	7.0/s	Y	Y
8.		Nikon Z6	3690	Y	3.2 / 2100	tilting	Y	1/8000s	12.0/s	n	Y
9.		Panasonic ZS70	1166	n	3.0 / 1040	tilting	Y	1/2000s	10.0/s	Y	Y
10.		Sony A7 II	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	Y
11.		Sony A7R III	3686	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
12.		Sony A7R IV	5760	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
13.		Sony A9	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
14.		Sony HX90V	638	n	3.0 / 921	tilting	n	1/2000s	10.0/s	Y	Y
15.		Sony HX95	638	n	3.0 / 922	tilting	n	1/2000s	10.0/s	Y	Y
16.		Sony HX400V	210	n	3.0 / 921	tilting	n	1/4000s	10.0/s	Y	Y
17.		Sony WX800	none	n	3.0 / 922	tilting	Y	1/2000s	10.0/s	Y	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 HX99 has one, while the A7 III does not. While the built-in flash of the HX99 is not very powerful, it can at times be useful as a fill-in light.

The reported shutter speed information refers to the use of the mechanical shutter. Yet, some cameras only have an electronic shutter, while others have an electronic shutter in addition to a mechanical one. In fact, the A7 III is one of those camera that have an additional electronic shutter, which makes completely silent shooting possible. However, this mode is less suitable for photographing moving objects (risk of rolling shutter) or shooting under artificial light sources (risk of flickering).

The Sony A7 III 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 HX99 and the A7 III write their files to SDXC or Memory Stick PRO Duo cards. The A7 III features dual card slots, which can be very useful in case a memory card fails. In contrast, the HX99 only has one slot. The A7 III supports UHS-II cards (on its first slot), while the HX99 can use UHS-I 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 Cyber-shot DSC-HX99 and Sony Alpha A7 III 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 HX99	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
2.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
3.		Canon SX70	-	stereo / mono	Y	-	micro	2.0	Y	-	Y
4.		Canon SX730	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
5.		Canon SX740	-	stereo / mono	-	-	micro	2.0	Y	-	Y
6.		Nikon A1000	-	stereo / mono	-	-	micro	2.0	Y	-	Y
7.		Nikon W300	-	stereo / mono	-	-	micro	2.0	Y	-	Y
8.		Nikon Z6	Y	stereo / mono	Y	Y	micro	3.1	Y	-	Y
9.		Panasonic ZS70	-	stereo / mono	-	-	micro	2.0	Y	-	-
10.		Sony A7 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
11.		Sony A7R III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
12.		Sony A7R IV	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
13.		Sony A9	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	Y
14.		Sony HX90V	-	stereo / mono	-	-	micro	2.0	Y	Y	-
15.		Sony HX95	-	stereo / mono	-	-	micro	2.0	Y	Y	Y
16.		Sony HX400V	Y	stereo / mono	-	-	micro	2.0	Y	Y	-
17.		Sony WX800	-	stereo / mono	-	-	micro	2.0	Y	Y	-

It is notable that the A7 III has a microphone port, which can help to improve the quality of audio recordings by attaching an external microphone. The HX99 does not feature such a mic input.

The A7 III is a recent model that features in the current product line-up of Sony. In contrast, the HX99 has been discontinued (but can be found pre-owned on ebay). There has not been a direct replacement model for the HX99 from Sony. Further information on the features and operation of the HX99 and A7 III can be found, respectively, in the Sony HX99 Manual (free pdf) or the online Sony A7 III Manual.

Review summary

So what conclusions can be drawn? Is the Sony HX99 better than the Sony A7 III or vice versa? Below is a summary of the relative strengths of each of the two contestants.

Arguments in favor of the Sony Cyber-shot DSC-HX99:

• Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Ready to shoot: Has a lens built-in, whereas the A7 III requires a separate lens.
• More compact: Is smaller (102x58mm vs 127x96mm) and thus needs less room in the bag.
• Less heavy: Is lighter even though it comes with a built-in lens (unlike the A7 III).
• Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
• More affordable: Was introduced at a lower price, despite coming with a built-in lens.
• More modern: Is somewhat more recent (announced 6 months after the A7 III).

Advantages of the Sony Alpha A7 III:

• More detail: Has more megapixels (24 vs 18MP), which boosts linear resolution by 18%.
• Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
• 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.
• Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
• Better sound: Can connect to an external microphone for higher quality sound recording.
• Better sound control: Has a headphone port that enables audio monitoring while recording.
• More detailed viewfinder: Has higher resolution electronic viewfinder (2359k vs 638k dots).
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/2000s) to freeze action.
• Less disturbing: Has an electronic shutter option for completely silent shooting.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• More flexible: Takes interchangeable lenses and can thus be used with specialty optics.
• Longer lasting: Gets more shots (610 versus 370) 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.
• Faster data transfer: Supports a more advanced USB protocol (3.1 vs 2.0).
• Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
• Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
• More heavily discounted: Has been on the market for longer (launched in February 2018).

If the count of individual advantages (bullet points above) is taken as a guide, the A7 III is the clear winner of the contest (21 : 8 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 HX99 and the Sony A7 III place the cameras among the top in their class? Find out in the latest Best Superzoom Camera and Best Mirrorless Interchangeable Lens Camera listings 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 partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the HX99 or the A7 III. 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 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 HX99	..	..	..	..	4/5	4.5/5	Aug 2018	449	ebay.com
2.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	1,999	amazon.com
3.		Canon SX70	..	+ +	3.5/5	..	3.5/5	3.5/5	Sep 2018	549	amazon.com
4.		Canon SX730	..	+	..	..	4/5	4/5	Apr 2017	399	ebay.com
5.		Canon SX740	..	+	3.5/5	..	4/5	4/5	Jul 2018	399	amazon.com
6.		Nikon A1000	..	+ +	3.5/5	..	3.5/5	3/5	Jan 2019	429	ebay.com
7.		Nikon W300	..	+	..	..	4/5	4/5	May 2017	389	ebay.com
8.		Nikon Z6	5/5	..	5/5	89/100	4.5/5	5/5	Aug 2018	1,999	ebay.com
9.		Panasonic ZS70	..	+ +	..	..	4/5	4/5	Apr 2017	449	ebay.com
10.		Sony A7 II	5/5	+	4/5	82/100	4.5/5	5/5	Nov 2014	1,999	ebay.com
11.		Sony A7R III	..	+ +	4/5	90/100	4.5/5	5/5	Oct 2017	3,199	ebay.com
12.		Sony A7R IV	5/5	+	4.5/5	91/100	4.5/5	5/5	Jul 2019	3,499	ebay.com
13.		Sony A9	5/5	+ +	4.8/5	89/100	5/5	5/5	Apr 2017	4,499	ebay.com
14.		Sony HX90V	4/5	+ +	..	..	4/5	4.5/5	Apr 2015	429	ebay.com
15.		Sony HX95	..	..	..	..	..	..	Aug 2018	429	ebay.com
16.		Sony HX400V	4/5	+ +	..	..	4/5	4/5	Feb 2014	499	ebay.com
17.		Sony WX800	..	..	..	..	..	..	Oct 2018	399	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. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, and comparisons of ratings among very different cameras or across long time periods 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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amazon.com

Other camera comparisons

Did this review help to inform your camera decision process? If you would like to see a different side-by-side camera review, just make a corresponding selection in the search boxes below. 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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