Sony A9 vs Olympus E-1

The Sony Alpha A9 and the Olympus E-1 are two professional cameras that were revealed to the public, respectively, in April 2017 and June 2003. The A9 is a mirrorless interchangeable lens camera, while the E-1 is a DSLR. The cameras are based on a full frame (A9) and a Four Thirds (E-1) sensor. The Sony has a resolution of 24 megapixels, whereas the Olympus provides 4.9 MP.

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

Headline Specifications

Sony A9		Olympus E-1
Mirrorless system camera		Digital single lens reflex
Sony E mount lenses		Four Thirds lenses
24 MP – Full Frame sensor		4.9 MP – Four Thirds sensor
4K/30p Video		no Video
ISO 100-51,200 (50 - 204,800)		ISO 100-800 (100 - 3,200)
Electronic viewfinder (3686k dots)		Optical viewfinder
3.0" LCD – 1440k dots		1.8" LCD – 134k dots
Tilting touchscreen		Fixed screen (not touch-sensitive)
20 shutter flaps per second		3 shutter flaps per second
In-body stabilization		Lens stabilization only
Weathersealed body		Weathersealed body
650 shots per battery charge		750 shots per battery charge
127 x 96 x 63 mm, 673 g		141 x 104 x 81 mm, 738 g

Check A9 offers at
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Check E-1 offers at
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Going beyond this snapshot of core features and characteristics, what are the differences between the Sony Alpha A9 and the Olympus E-1? 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 A9 and the Olympus E-1 are illustrated 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.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Olympus E-1 is notably larger (20 percent) than the Sony A9. Moreover, the E-1 is markedly heavier (10 percent) than the A9. 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. A larger imaging sensor will tend to go along with bigger and heavier lenses, although exceptions exist. You can compare the optics available for the two cameras in the Sony FE Lens Catalog (A9) and the Four Thirds Lens Catalog (E-1). Mirrorless cameras, such as the Sony A9, have moreover the advantage that they have a relatively short flange to focal plane distance and can thus use many lenses from other systems via adapters.

Concerning battery life, the A9 gets 650 shots out of its Sony NP-FZ100 battery, while the E-1 can take 750 images on a single charge of its Olympus BLM-1 power pack. The power pack in the A9 can be charged via the USB port, so that it is not always necessary to take the battery charger along when travelling.

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.		Sony A9	127 mm	96 mm	63 mm	673 g	650	Y	Apr 2017	4,499	ebay.com
2.		Olympus E-1	141 mm	104 mm	81 mm	738 g	750	Y	Jun 2003	1,699	ebay.com
3.		Leica Digilux 3	146 mm	87 mm	77 mm	606 g	750	n	Sep 2006	1,499	ebay.com
4.		Nikon Z6	134 mm	101 mm	67 mm	675 g	310	Y	Aug 2018	1,999	ebay.com
5.		Olympus E-5	142 mm	117 mm	75 mm	873 g	750	Y	Sep 2010	1,699	ebay.com
6.		Olympus E-3	142 mm	116 mm	75 mm	876 g	750	Y	Oct 2007	1,699	ebay.com
7.		Olympus E-330	140 mm	87 mm	72 mm	637 g	750	n	Jan 2006	999	ebay.com
8.		Olympus E-300	147 mm	85 mm	64 mm	624 g	750	n	Sep 2004	799	ebay.com
9.		Sony A7R V	131 mm	97 mm	82 mm	723 g	530	Y	Oct 2022	3,899	amazon.com
10.		Sony A7R IIIA	127 mm	96 mm	74 mm	650 g	650	Y	Apr 2021	3,199	amazon.com
11.		Sony A9 II	129 mm	96 mm	76 mm	678 g	690	Y	Oct 2019	4,499	amazon.com
12.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	1,999	amazon.com
13.		Sony A7R III	127 mm	96 mm	74 mm	650 g	650	Y	Oct 2017	3,199	ebay.com
14.		Sony A7R II	127 mm	96 mm	60 mm	625 g	290	Y	Jun 2015	3,199	ebay.com
15.		Sony A7S II	127 mm	96 mm	60 mm	627 g	370	Y	Sep 2015	2,999	ebay.com
16.		Sony A7 II	127 mm	96 mm	60 mm	599 g	350	Y	Nov 2014	1,999	ebay.com
17.		Sony A99	147 mm	111 mm	78 mm	812 g	500	Y	Sep 2012	2,799	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 manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The E-1 was launched at a markedly lower price (by 62 percent) than the A9, 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 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 Sony A9 features a full frame sensor and the Olympus E-1 a Four Thirds sensor. The sensor area in the E-1 is 73 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.0 and 2.0. The sensor in the A9 has a native 3:2 aspect ratio, while the one in the E-1 offers a 4:3 aspect.

With 24MP, the A9 offers a higher resolution than the E-1 (4.9MP), but the A9 has smaller individual pixels (pixel pitch of 5.94μm versus 6.78μm for the E-1). However, the A9 is a much more recent model (by 13 years and 9 months) than the E-1, and its sensor will have benefitted from technological advances during this time that enhance the light gathering capacity of its pixels.

The resolution advantage of the Sony A9 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A9 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 Olympus E-1 are 12.8 x 9.6 inches or 32.5 x 24.4 cm for good quality, 10.2 x 7.7 inches or 26 x 19.5 cm for very good quality, and 8.5 x 6.4 inches or 21.7 x 16.3 cm for excellent quality prints.

The A9 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.

The Sony Alpha A9 has a native sensitivity range from ISO 100 to ISO 51200, which can be extended to ISO 50-204800. The corresponding ISO settings for the Olympus E-1 are ISO 100 to ISO 800, with the possibility to increase the ISO range to 100-3200.

In terms of underlying technology, the A9 is build around a Stacked BSI-CMOS sensor, while the E-1 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 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 A9	Full Frame	24.0	6000	4000	4K/30p	24.9	13.3	3517	92
2.		Olympus E-1	Four Thirds	4.9	2560	1920	none	20.0	9.7	-145	44
3.		Leica Digilux 3	Four Thirds	7.4	3136	2352	none	21.0	10.6	127	53
4.		Nikon Z6	Full Frame	24.3	6048	4024	4K/30p	25.3	14.3	3299	95
5.		Olympus E-5	Four Thirds	12.2	4032	3024	720/30p	21.6	10.5	519	56
6.		Olympus E-3	Four Thirds	10.0	3648	2736	none	21.6	10.5	571	56
7.		Olympus E-330	Four Thirds	7.4	3136	2352	none	20.8	10.4	73	52
8.		Olympus E-300	Four Thirds	8.0	3264	2448	none	20.4	10.1	-40	48
9.		Sony A7R V	Full Frame	60.2	9504	6336	8k/24p	26.5	14.8	3187	100
10.		Sony A7R IIIA	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
11.		Sony A9 II	Full Frame	24.0	6000	4000	4K/30p	25.0	14.0	3434	93
12.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
13.		Sony A7R III	Full Frame	42.2	7952	5304	4K/30p	26.0	14.7	3523	100
14.		Sony A7R II	Full Frame	42.2	7952	5304	4K/30p	26.0	13.9	3434	98
15.		Sony A7S II	Full Frame	12.0	4240	2832	4K/30p	23.6	13.3	2993	85
16.		Sony A7 II	Full Frame	24.0	6000	4000	1080/60p	24.9	13.6	2449	90
17.		Sony A99	Full Frame	24.0	6000	4000	1080/60p	25.0	14.0	1555	89
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 A9 indeed provides movie recording capabilities, while the E-1 does not. The highest resolution format that the A9 can use is 4K/30p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the A9 has an electronic viewfinder (3686k dots), while the E-1 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 A9 has a higher magnification than the one of the E-1 (0.78x vs 0.48x), 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 Sony A9, the Olympus E-1, 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.		Sony A9	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
2.		Olympus E-1	optical	Y	1.8 / 134	fixed	n	1/4000s	3.0/s	n	n
3.		Leica Digilux 3	optical	n	2.5 / 207	fixed	n	1/4000s	3.0/s	Y	n
4.		Nikon Z6	3690	Y	3.2 / 2100	tilting	Y	1/8000s	12.0/s	n	Y
5.		Olympus E-5	optical	Y	3.0 / 920	swivel	n	1/8000s	5.0/s	Y	Y
6.		Olympus E-3	optical	Y	2.5 / 230	swivel	n	1/8000s	5.0/s	Y	Y
7.		Olympus E-330	optical	n	2.5 / 215	tilting	n	1/4000s	3.0/s	Y	n
8.		Olympus E-300	optical	n	1.8 / 134	fixed	n	1/4000s	2.5/s	Y	n
9.		Sony A7R V	9440	n	3.2 / 2100	full-flex	Y	1/8000s	10.0/s	n	Y
10.		Sony A7R IIIA	3686	n	3.0 / 2340	tilting	Y	1/8000s	10.0/s	n	Y
11.		Sony A9 II	3686	n	3.0 / 1440	tilting	Y	1/8000s	20.0/s	n	Y
12.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
13.		Sony A7R III	3686	n	3.0 / 1440	tilting	Y	1/8000s	10.0/s	n	Y
14.		Sony A7R II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
15.		Sony A7S II	2400	n	3.0 / 1229	tilting	n	1/8000s	5.0/s	n	Y
16.		Sony A7 II	2400	n	3.0 / 1230	tilting	n	1/8000s	5.0/s	n	Y
17.		Sony A99	2359	Y	3.0 / 1229	full-flex	n	1/8000s	6.0/s	n	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One feature that differentiates the A9 and the E-1 is in-body image stabilization (IBIS). The A9 reduces the risk of handshake-induced blur with all attached lenses, while the E-1 offers no blur reduction with lenses that themselves do not provide optical image stabilization.

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 A9 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 A9 writes its imaging data to SDXC or Memory Stick PRO Duo cards, while the E-1 uses Compact Flash or xD Picture cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails.

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 A9 and Olympus E-1 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 A9	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	Y
2.		Olympus E-1	Y	- / -	-	-	-	2.0	-	-	-
3.		Leica Digilux 3	Y	stereo / mono	-	-	-	2.0	-	-	-
4.		Nikon Z6	Y	stereo / mono	Y	Y	micro	3.1	Y	-	Y
5.		Olympus E-5	Y	stereo / -	-	-	mini	2.0	-	-	-
6.		Olympus E-3	Y	- / -	-	-	-	2.0	-	-	-
7.		Olympus E-330	Y	- / -	-	-	-	2.0	-	-	-
8.		Olympus E-300	Y	- / -	-	-	-	2.0	-	-	-
9.		Sony A7R V	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
10.		Sony A7R IIIA	Y	stereo / mono	Y	Y	micro	3.2	Y	Y	Y
11.		Sony A9 II	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
12.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
13.		Sony A7R III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y
14.		Sony A7R II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
15.		Sony A7S II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
16.		Sony A7 II	Y	stereo / mono	Y	Y	micro	2.0	Y	Y	-
17.		Sony A99	Y	stereo / mono	Y	Y	mini	2.0	-	-	-

It is notable that the A9 offers wifi support, while the E-1 does not. Wifi can be a very convenient means to transfer image data to an off-camera location.

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

Both the A9 and the E-1 have been discontinued, but can regularly be found used on ebay. The E-1 was replaced by the Olympus E-3, while the A9 was followed by the Sony A9 II. Further information on the features and operation of the A9 and E-1 can be found, respectively, in the Sony A9 Manual (free pdf) or the online Olympus E-1 Manual.

Review summary

So how do things add up? Which of the two cameras – the Sony A9 or the Olympus E-1 – 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.

Reasons to prefer the Sony Alpha A9:

• More detail: Offers more megapixels (24 vs 4.9MP) with a 125% higher linear resolution.
• Better image quality: Features a larger and more technologically advanced imaging sensor.
• Richer colors: The sensor size advantage translates into images with better, more accurate colors.
• More dynamic range: Larger sensor captures a wider spectrum of light and dark details.
• Better low-light sensitivity: Larger sensor produces good images even in poorly lit environments.
• Broader imaging potential: Can record not only still images but also 4K/30p movies.
• 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 0.48x).
• Larger screen: Has a bigger rear LCD (3.0" vs 1.8") for image review and settings control.
• More detailed LCD: Has a higher resolution rear screen (1440k vs 134k dots).
• More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
• Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (20 vs 3 flaps/sec) to capture the decisive moment.
• Less disturbing: Has an electronic shutter option for completely silent shooting.
• More compact: Is smaller (127x96mm vs 141x104mm) and thus needs less room in the bag.
• Easier travel charging: Can be conveniently charged via its USB port.
• Sharper images: Has hand-shake reducing image stabilization built-in.
• More legacy lens friendly: Can take a broad range of non-native lenses via adapters.
• 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.
• Easier wireless transfer: Supports Bluetooth for image sharing without cables.
• More modern: Reflects 13 years and 9 months of technical progress since the E-1 launch.

Arguments in favor of the Olympus E-1:

• Brighter framing: Features an optical viewfinder for clear, lag-free composition.
• Easier setting verification: Features a control panel on top to check shooting parameters.
• Longer lasting: Gets more shots (750 versus 650) out of a single battery charge.
• More affordable: Was introduced into a lower priced category (62 percent cheaper at launch).
• More heavily discounted: Has been around for much longer (launched in June 2003).

If the number of relative strengths (bullet points above) is taken as a guide, the A9 is the clear winner of the match-up (24 : 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 A9 and the Olympus E-1 place the cameras among the top in their class? Find out in the latest Best Mirrorless Interchangeable Lens Camera and Best DSLR Camera listings 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 says little about, for example, the shooting experience and imaging performance of the A9 and the E-1 in practical situations. User reviews that are available, for instance, at amazon can sometimes shed light on these issues, but such feedback is all too often partial, inconsistent, and inaccurate.

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.		Sony A9	5/5	+ +	4.8/5	89/100	5/5	5/5	Apr 2017	4,499	ebay.com
2.		Olympus E-1	..	..	..	+	o	..	Jun 2003	1,699	ebay.com
3.		Leica Digilux 3	..	..	..	..	..	..	Sep 2006	1,499	ebay.com
4.		Nikon Z6	5/5	..	5/5	89/100	4.5/5	5/5	Aug 2018	1,999	ebay.com
5.		Olympus E-5	4/5	..	..	75/100	4/5	4.5/5	Sep 2010	1,699	ebay.com
6.		Olympus E-3	..	88/100	..	+ +	o	4/5	Oct 2007	1,699	ebay.com
7.		Olympus E-330	..	..	..	+	o	..	Jan 2006	999	ebay.com
8.		Olympus E-300	..	..	..	+	o	4.5/5	Sep 2004	799	ebay.com
9.		Sony A7R V	5/5	+ +	4.5/5	92/100	..	..	Oct 2022	3,899	amazon.com
10.		Sony A7R IIIA	..	+ +	4/5	90/100	4.5/5	5/5	Apr 2021	3,199	amazon.com
11.		Sony A9 II	..	..	5/5	90/100	5/5	5/5	Oct 2019	4,499	amazon.com
12.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	1,999	amazon.com
13.		Sony A7R III	..	+ +	4/5	90/100	4.5/5	5/5	Oct 2017	3,199	ebay.com
14.		Sony A7R II	5/5	+ +	5/5	90/100	5/5	5/5	Jun 2015	3,199	ebay.com
15.		Sony A7S II	5/5	+	..	..	4.5/5	5/5	Sep 2015	2,999	ebay.com
16.		Sony A7 II	5/5	+	4/5	82/100	4.5/5	5/5	Nov 2014	1,999	ebay.com
17.		Sony A99	5/5	..	..	84/100	4.5/5	4.5/5	Sep 2012	2,799	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

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