Nikon Z5 II vs OM System OM-3

The Nikon Z5 II and the OM System OM-3 are two digital cameras that were announced, respectively, in April 2025 and February 2025. Both the Z5 II and the OM-3 are mirrorless interchangeable lens cameras that are based on a full frame (Z5 II) and a Four Thirds (OM-3) sensor. The Nikon has a resolution of 24.4 megapixels, whereas the OM System provides 20.2 MP.

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

Headline Specifications

Nikon Z5 II		OM System OM-3
Mirrorless system camera		Mirrorless system camera
Nikon Z mount lenses		Micro Four Thirds lenses
24.4 MP – Full Frame sensor		20.2 MP – Four Thirds sensor
4K/60p Video		4K/60p Video
ISO 100-51,200 (50 - 204,800)		ISO 80-25,600 (80 - 102,400)
Electronic viewfinder (3690k dots)		Electronic viewfinder (2360k dots)
3.2" LCD – 2100k dots		3.0" LCD – 1640k dots
Swivel touchscreen		Swivel touchscreen
14 shutter flaps per second		6 shutter flaps per second
In-body stabilization		In-body stabilization
Weathersealed body		Weathersealed body
330 shots per battery charge		590 shots per battery charge
134 x 101 x 72 mm, 700 g		139 x 89 x 46 mm, 496 g

Check Z5 II price at
amazon.com
Check OM-3 price at
amazon.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon Z5 II and the OM System OM-3? 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 Nikon Z5 II and the OM System OM-3. 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 OM-3 can be obtained in two different colors (black, silver), while the Z5 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 OM System OM-3 is notably smaller (9 percent) than the Nikon Z5 II. Moreover, the OM-3 is markedly lighter (29 percent) than the Z5 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 Z5 II gets 330 shots out of its Nikon EN-EL15c battery, while the OM-3 can take 590 images on a single charge of its OM System BLX-1 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. 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.		Nikon Z5 II	134 mm	101 mm	72 mm	700 g	330	Y	Apr 2025	US$ 1 699	amazon.com
2.		OM System OM-3	139 mm	89 mm	46 mm	496 g	590	Y	Feb 2025	US$ 1 999	amazon.com
3.		Nikon Z5	134 mm	101 mm	67 mm	675 g	470	Y	Jul 2020	US$ 1 399	ebay.com
4.		Nikon Z6	134 mm	101 mm	67 mm	675 g	310	Y	Aug 2018	US$ 1 999	ebay.com
5.		Nikon Z6 II	134 mm	101 mm	70 mm	705 g	410	Y	Oct 2020	US$ 1 999	amazon.com
6.		Nikon Z6 III	139 mm	102 mm	74 mm	670 g	380	Y	Jun 2024	US$ 2 499	amazon.com
7.		Nikon Z7	134 mm	101 mm	67 mm	675 g	330	Y	Aug 2018	US$ 3 399	ebay.com
8.		Nikon Z7 II	134 mm	101 mm	70 mm	705 g	420	Y	Oct 2020	US$ 2 999	amazon.com
9.		Nikon Zf	144 mm	103 mm	49 mm	710 g	380	Y	Sep 2023	US$ 1 999	amazon.com
10.		Olympus E-M1 II	134 mm	91 mm	67 mm	574 g	440	Y	Sep 2016	US$ 1 999	ebay.com
11.		Olympus E-M1 III	134 mm	91 mm	69 mm	580 g	420	Y	Feb 2020	US$ 1 799	ebay.com
12.		OM System OM-1	135 mm	92 mm	73 mm	599 g	520	Y	Feb 2022	US$ 2 199	ebay.com
13.		OM System OM-1 II	135 mm	92 mm	73 mm	599 g	500	Y	Jan 2024	US$ 2 399	amazon.com
14.		OM System OM-5 II	125 mm	85 mm	50 mm	414 g	310	Y	Jun 2025	US$ 1 199	amazon.com
15.		Panasonic S5	133 mm	98 mm	82 mm	714 g	440	Y	Sep 2020	US$ 1 999	amazon.com
16.		Panasonic S5 II	134 mm	102 mm	90 mm	740 g	370	Y	Jan 2023	US$ 1 999	amazon.com
17.		Sony A7 III	127 mm	96 mm	74 mm	650 g	610	Y	Feb 2018	US$ 1 999	amazon.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 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 Z5 II was launched at a somewhat lower price (by 15 percent) than the OM-3, which makes it more attractive for photographers on a tight budget. 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. Moreover, a large sensor camera will give the photographer more control over depth-of-field in the image and, thus, the ability to better 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 Nikon Z5 II features a full frame sensor and the OM System OM-3 a Four Thirds sensor. The sensor area in the OM-3 is 74 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 Z5 II has a native 3:2 aspect ratio, while the one in the OM-3 offers a 4:3 aspect.

With 24.4MP, the Z5 II offers a higher resolution than the OM-3 (20.2MP), but the Z5 II nevertheless has larger individual pixels (pixel pitch of 5.93μm versus 3.34μm for the OM-3) due to its larger sensor. It is noteworthy in this context that the two cameras were released in close succession, so that their sensors are from the same technological generation. Coming back to sensor resolution, it should be mentioned that the OM-3 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The resolution advantage of the Nikon Z5 II implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the Z5 II for good quality output (200 dots per inch) amounts to 30.2 x 20.2 inches or 76.8 x 51.2 cm, for very good quality (250 dpi) 24.2 x 16.1 inches or 61.4 x 41 cm, and for excellent quality (300 dpi) 20.2 x 13.4 inches or 51.2 x 34.1 cm. The corresponding values for the OM System OM-3 are 25.9 x 19.4 inches or 65.8 x 49.4 cm for good quality, 20.7 x 15.6 inches or 52.7 x 39.5 cm for very good quality, and 17.3 x 13 inches or 43.9 x 32.9 cm for excellent quality prints.

Unlike the Z5 II, the OM-3 has the capacity to capture high quality composite images (80MP) 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 Nikon Z5 II 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 OM System OM-3 are ISO 80 to ISO 25600, with the possibility to increase the ISO range to 80-102400.

In terms of underlying technology, the Z5 II is build around a BSI-CMOS sensor, while the OM-3 uses a Stacked 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.		Nikon Z5 II	Full Frame	24.4	6048	4032	4K/60p	25.4	14.8	3398	97
2.		OM System OM-3	Four Thirds	20.2	5184	3888	4K/60p	23.4	13.7	1852	78
3.		Nikon Z5	Full Frame	24.2	6016	4016	4K/30p	25.3	14.3	2929	95
4.		Nikon Z6	Full Frame	24.3	6048	4024	4K/30p	25.3	14.3	3299	95
5.		Nikon Z6 II	Full Frame	24.3	6048	4024	4K/60p	25.0	14.4	3303	94
6.		Nikon Z6 III	Full Frame	24.3	6048	4024	6K/60p	25.4	14.8	3318	97
7.		Nikon Z7	Full Frame	45.4	8256	5504	4K/30p	26.3	14.6	2668	99
8.		Nikon Z7 II	Full Frame	45.4	8256	5504	4K/60p	26.3	14.7	2841	100
9.		Nikon Zf	Full Frame	24.3	6048	4024	4K/60p	25.4	14.7	3243	96
10.		Olympus E-M1 II	Four Thirds	20.2	5184	3888	4K/30p	23.7	12.8	1312	80
11.		Olympus E-M1 III	Four Thirds	20.2	5184	3888	4K/30p	23.3	13.1	1356	76
12.		OM System OM-1	Four Thirds	20.2	5184	3888	4K/60p	23.4	13.4	1553	77
13.		OM System OM-1 II	Four Thirds	20.2	5184	3888	4K/60p	23.4	13.6	1749	78
14.		OM System OM-5 II	Four Thirds	20.2	5184	3888	4K/30p	23.4	13.7	1889	78
15.		Panasonic S5	Full Frame	24.0	6000	4000	4K/60p	25.1	14.5	2697	94
16.		Panasonic S5 II	Full Frame	24.0	6000	4000	6K/30p	25.4	14.6	3158	96
17.		Sony A7 III	Full Frame	24.0	6000	4000	4K/30p	25.0	14.7	3730	96
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. 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 (4K/60p).

Feature comparison

Apart from body and sensor, cameras can and do differ across a variety of features. The two cameras under consideration are similar with respect to both having an electronic viewfinder. However, the one in the Z5 II offers a substantially higher resolution than the one in the OM-3 (3690k vs 2360k dots). The adjacent table lists some of the other core features of the Nikon Z5 II and OM System OM-3 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.		Nikon Z5 II	3690	n	3.2 / 2100	swivel	Y	1/8000s	14.0/s	n	Y
2.		OM System OM-3	2360	n	3.0 / 1640	swivel	Y	1/8000s	6.0/s	n	Y
3.		Nikon Z5	3690	n	3.2 / 1040	tilting	Y	1/8000s	4.5/s	n	Y
4.		Nikon Z6	3690	Y	3.2 / 2100	tilting	Y	1/8000s	12.0/s	n	Y
5.		Nikon Z6 II	3690	Y	3.2 / 2100	tilting	Y	1/8000s	14.0/s	n	Y
6.		Nikon Z6 III	5760	Y	3.2 / 2100	swivel	Y	1/8000s	14.0/s	n	Y
7.		Nikon Z7	3690	Y	3.2 / 2100	tilting	Y	1/8000s	9.0/s	n	Y
8.		Nikon Z7 II	3690	Y	3.2 / 2100	tilting	Y	1/8000s	10.0/s	n	Y
9.		Nikon Zf	3690	n	3.2 / 2100	swivel	Y	1/8000s	14.0/s	n	Y
10.		Olympus E-M1 II	2360	n	3.0 / 1037	swivel	Y	1/8000s	18.0/s	n	Y
11.		Olympus E-M1 III	2360	n	3.0 / 1037	swivel	Y	1/8000s	18.0/s	n	Y
12.		OM System OM-1	5760	n	3.0 / 1640	swivel	Y	1/8000s	10.0/s	n	Y
13.		OM System OM-1 II	5760	n	3.0 / 1640	swivel	Y	1/8000s	10.0/s	n	Y
14.		OM System OM-5 II	2360	n	3.0 / 1040	swivel	Y	1/8000s	10.0/s	n	Y
15.		Panasonic S5	2360	n	3.0 / 1840	swivel	Y	1/8000s	7.0/s	n	Y
16.		Panasonic S5 II	3680	n	3.0 / 1840	swivel	Y	1/8000s	9.0/s	n	Y
17.		Sony A7 III	2359	n	3.0 / 922	tilting	Y	1/8000s	10.0/s	n	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

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, both cameras under consideration feature an 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 Nikon Z5 II and the OM System OM-3 both have 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 Z5 II and the OM-3 write their files to SDXC cards. The Z5 II features dual card slots, which can be very useful in case a memory card fails. In contrast, the OM-3 only has one slot. Both cameras support UHS-II cards, which provide for Ultra High Speed data transfer of up to 312 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 Nikon Z5 II and OM System OM-3 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.		Nikon Z5 II	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
2.		OM System OM-3	Y	stereo / mono	Y	Y	micro	3.0	Y	-	Y
3.		Nikon Z5	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
4.		Nikon Z6	Y	stereo / mono	Y	Y	micro	3.1	Y	-	Y
5.		Nikon Z6 II	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
6.		Nikon Z6 III	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
7.		Nikon Z7	Y	stereo / mono	Y	Y	micro	3.1	Y	-	Y
8.		Nikon Z7 II	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
9.		Nikon Zf	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
10.		Olympus E-M1 II	Y	stereo / mono	Y	Y	micro	3.0	Y	-	-
11.		Olympus E-M1 III	Y	stereo / mono	Y	Y	micro	3.1	Y	-	Y
12.		OM System OM-1	Y	stereo / mono	Y	Y	micro	3.0	Y	-	Y
13.		OM System OM-1 II	Y	stereo / mono	Y	Y	micro	3.0	Y	-	Y
14.		OM System OM-5 II	Y	stereo / mono	Y	-	micro	2.0	Y	-	Y
15.		Panasonic S5	Y	stereo / mono	Y	Y	micro	3.2	Y	-	Y
16.		Panasonic S5 II	Y	stereo / mono	Y	Y	full	3.2	Y	-	Y
17.		Sony A7 III	Y	stereo / mono	Y	Y	micro	3.1	Y	Y	Y

Both the Z5 II and the OM-3 are recent models that are part of the current product line-up. The Z5 II replaced the earlier Nikon Z5, while the OM-3 does not have a direct predecessor. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Nikon and OM System websites.

Review summary

So what is the bottom line? Which of the two cameras – the Nikon Z5 II or the OM System OM-3 – has the upper hand? Is one clearly better than the other? A synthesis of the relative strong points of each of the models is listed below.

Arguments in favor of the Nikon Z5 II:

• More detail: Offers more megapixels (24.4 vs 20.2MP) with a 12% higher linear resolution.
• 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.
• More detailed viewfinder: Has higher resolution electronic viewfinder (3690k vs 2360k dots).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.80x vs 0.69x).
• Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
• More detailed LCD: Has a higher resolution rear screen (2100k vs 1640k dots).
• Faster burst: Shoots at higher frequency (14 vs 6 flaps/sec) to capture the decisive moment.
• Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
• More affordable: Was introduced into a lower priced segment (15 percent cheaper at launch).

Advantages of the OM System OM-3:

• 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.
• Less heavy: Has a lower weight (by 204g or 29 percent) and is thus easier to take along.
• Longer lasting: Gets more shots (590 versus 330) out of a single battery charge.

If the count of relative strengths (bullet points above) is taken as a measure, the Z5 II is the clear winner of the match-up (13 : 4 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 Nikon Z5 II and the OM System OM-3 place the cameras among the top in their class? Find out in the latest Best Mirrorless Interchangeable Lens 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 Z5 II or the OM-3 perform in practice. 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 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.		Nikon Z5 II	..	..	..	..	..	..	Apr 2025	US$ 1 699	amazon.com
2.		OM System OM-3	..	..	..	86/100	..	..	Feb 2025	US$ 1 999	amazon.com
3.		Nikon Z5	4/5	..	4/5	89/100	4.5/5	4/5	Jul 2020	US$ 1 399	ebay.com
4.		Nikon Z6	5/5	..	5/5	89/100	4.5/5	5/5	Aug 2018	US$ 1 999	ebay.com
5.		Nikon Z6 II	4.5/5	..	4/5	89/100	4.5/5	4.5/5	Oct 2020	US$ 1 999	amazon.com
6.		Nikon Z6 III	..	..	..	..	..	..	Jun 2024	US$ 2 499	amazon.com
7.		Nikon Z7	5/5	+	4.8/5	89/100	4.5/5	5/5	Aug 2018	US$ 3 399	ebay.com
8.		Nikon Z7 II	4.5/5	..	4.5/5	..	4.5/5	4.5/5	Oct 2020	US$ 2 999	amazon.com
9.		Nikon Zf	4.5/5	..	4.5/5	90/100	4.5/5	5/5	Sep 2023	US$ 1 999	amazon.com
10.		Olympus E-M1 II	5/5	+ +	5/5	85/100	4.5/5	4.5/5	Sep 2016	US$ 1 999	ebay.com
11.		Olympus E-M1 III	5/5	..	5/5	83/100	4.5/5	4/5	Feb 2020	US$ 1 799	ebay.com
12.		OM System OM-1	5/5	..	..	87/100	5/5	4.5/5	Feb 2022	US$ 2 199	ebay.com
13.		OM System OM-1 II	..	..	..	..	..	..	Jan 2024	US$ 2 399	amazon.com
14.		OM System OM-5 II	..	..	..	..	..	..	Jun 2025	US$ 1 199	amazon.com
15.		Panasonic S5	4.5/5	+ +	4.5/5	88/100	4.5/5	4.5/5	Sep 2020	US$ 1 999	amazon.com
16.		Panasonic S5 II	4.5/5	+ +	5/5	90/100	4.5/5	5/5	Jan 2023	US$ 1 999	amazon.com
17.		Sony A7 III	..	+ +	4.5/5	89/100	5/5	5/5	Feb 2018	US$ 1 999	amazon.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.

Check Z5 II price at
amazon.com
Check OM-3 price at
amazon.com

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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Check Z5 II price at
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