Nikon D3100 vs Panasonic G3

The Nikon D3100 and the Panasonic Lumix DMC-G3 are two digital cameras that were announced, respectively, in August 2010 and May 2011. The D3100 is a DSLR, while the G3 is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (D3100) and a Four Thirds (G3) sensor. The Nikon has a resolution of 14.2 megapixels, whereas the Panasonic provides 15.8 MP.

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

Headline Specifications

Nikon D3100		Panasonic G3
Digital single lens reflex		Mirrorless system camera
Nikon F mount lenses		Micro Four Thirds lenses
14.2 MP – APS-C sensor		15.8 MP – Four Thirds sensor
1080/24p Video		1080/60i Video
ISO 100-3,200 (100 - 12,800)		ISO 160-6,400
Optical viewfinder		Electronic viewfinder (1440k dots)
3.0" LCD – 230k dots		3.0" LCD – 460k dots
Fixed screen (not touch-sensitive)		Swivel touchscreen
3 shutter flaps per second		4 shutter flaps per second
550 shots per battery charge		270 shots per battery charge
124 x 96 x 75 mm, 505 g		115 x 84 x 47 mm, 336 g

Check D3100 offers at
ebay.com
Check G3 offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon D3100 and the Panasonic Lumix DMC-G3? 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 Nikon D3100 and the Panasonic G3 are illustrated 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 D3100 can be obtained in two different colors (black, red), while the G3 is available in four color-versions (black, brown, red, white).

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Panasonic G3 is notably smaller (19 percent) than the Nikon D3100. Moreover, the G3 is markedly lighter (33 percent) than the D3100. In this context, it is worth noting that neither the D3100 nor the G3 are weather-sealed.

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 Nikon Lens Catalog (D3100) and the Micro Four Thirds Lens Catalog (G3). Mirrorless cameras, such as the G3, have moreover the advantage that they can use many lenses from other systems via adapters, as they have a relatively short flange to focal plane distance.

Concerning battery life, the D3100 gets 550 shots out of its EN-EL14 battery, while the G3 can take 270 images on a single charge of its DMW-BLD10 power pack.

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.		Nikon D3100	124 mm	96 mm	75 mm	505 g	550	n	Aug 2010	599	ebay.com
2.		Panasonic G3	115 mm	84 mm	47 mm	336 g	270	n	May 2011	599	ebay.com
3.		Nikon D3200	125 mm	96 mm	77 mm	505 g	540	n	Apr 2012	599	ebay.com
4.		Nikon D5100	128 mm	97 mm	79 mm	560 g	660	n	Apr 2011	749	ebay.com
5.		Nikon D7000	132 mm	105 mm	77 mm	780 g	1050	Y	Sep 2010	1,499	ebay.com
6.		Nikon D3000	126 mm	97 mm	64 mm	536 g	500	n	Jul 2009	599	ebay.com
7.		Nikon D5000	127 mm	104 mm	80 mm	590 g	510	n	Apr 2009	749	ebay.com
8.		Nikon D60	126 mm	94 mm	64 mm	522 g	500	n	Jan 2008	629	ebay.com
9.		Nikon D40X	124 mm	94 mm	64 mm	522 g	520	n	Mar 2007	729	ebay.com
10.		Nikon D40	124 mm	94 mm	64 mm	522 g	470	n	Nov 2006	499	ebay.com
11.		Panasonic G6	122 mm	85 mm	71 mm	390 g	340	n	Apr 2013	599	ebay.com
12.		Panasonic G5	120 mm	83 mm	71 mm	396 g	320	n	Jul 2012	599	ebay.com
13.		Panasonic GX1	116 mm	68 mm	39 mm	318 g	320	n	Nov 2011	699	ebay.com
14.		Panasonic G2	124 mm	84 mm	74 mm	428 g	360	n	Mar 2010	599	ebay.com
15.		Panasonic GH2	124 mm	90 mm	76 mm	442 g	330	n	Sep 2010	899	ebay.com
16.		Sony NEX-5N	111 mm	59 mm	38 mm	269 g	460	n	Aug 2011	699	ebay.com
17.		Sony NEX-C3	110 mm	60 mm	33 mm	225 g	400	n	Jun 2011	599	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 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 two cameras under review were launched at the same price and fall into the same market segment. Normally, street prices remain initially close to the MSRP, but after a couple of months, the first discounts appear. 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. 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. 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 Nikon D3100 features an APS-C sensor and the Panasonic G3 a Four Thirds sensor. The sensor area in the G3 is 37 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.5 and 2.0. The sensor in the D3100 has a native 3:2 aspect ratio, while the one in the G3 offers a 4:3 aspect.

Despite having a smaller sensor, the G3 offers a higher resolution of 15.8 megapixels, compared with 14.2 MP of the D3100. This megapixels advantage comes at the cost of a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 3.77μm versus 5.01μm for the D3100). However, it should be noted that the G3 is a somewhat more recent model (by 8 months) than the D3100, and its sensor might have benefitted from technological advances during this time that partly offset its pixel-size disadvantage.

The Nikon D3100 has a native sensitivity range from ISO 100 to ISO 3200, which can be extended to ISO 100-12800. The corresponding ISO settings for the Panasonic Lumix DMC-G3 are ISO 160 to ISO 6400 (no boost).

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 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"). Of the two cameras under review, the D3100 provides substantially higher image quality than the G3, with an overall score that is 11 points higher. This advantage is based on 1.5 bits higher color depth, 0.7 EV in additional dynamic range, and 0.5 stops in additional low light sensitivity. The following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.

Sensor Characteristics

		Camera Model	Sensor Class	Resolution (MP)	Horiz. Pixels	Vert. Pixels	Video Format	DXO Portrait	DXO Landscape	DXO Sports	DXO Overall
1.		Nikon D3100	APS-C	14.2	4608	3072	1080/24p	22.5	11.3	919	67
2.		Panasonic G3	Four Thirds	15.8	4592	3448	1080/60i	21.0	10.6	667	56
3.		Nikon D3200	APS-C	24.1	6016	4000	1080/30p	24.1	13.2	1131	81
4.		Nikon D5100	APS-C	16.1	4928	3264	1080/30p	23.5	13.6	1183	80
5.		Nikon D7000	APS-C	16.1	4928	3264	1080/24p	23.5	13.9	1167	80
6.		Nikon D3000	APS-C	10.0	3872	2592	none	22.3	11.1	563	62
7.		Nikon D5000	APS-C	12.2	4288	2848	720/24p	22.7	12.5	868	72
8.		Nikon D60	APS-C	10.0	3872	2592	none	22.5	11.4	562	65
9.		Nikon D40X	APS-C	10.0	3872	2592	none	22.4	11.4	516	63
10.		Nikon D40	APS-C	6.0	3008	2000	none	21.0	11.0	561	56
11.		Panasonic G6	Four Thirds	15.9	4608	3456	1080/60p	21.3	11.5	639	61
12.		Panasonic G5	Four Thirds	15.9	4608	3456	1080/60p	21.4	11.6	618	61
13.		Panasonic GX1	Four Thirds	15.8	4592	3448	1080/60p	20.8	10.6	703	55
14.		Panasonic G2	Four Thirds	12.0	4000	3000	720/30p	21.2	10.3	493	53
15.		Panasonic GH2	Four Thirds	15.9	4608	3456	1080/60i	21.2	11.3	655	60
16.		Sony NEX-5N	APS-C	16.0	4912	3264	1080/60i	23.6	12.7	1079	77
17.		Sony NEX-C3	APS-C	16.0	4912	3264	720/30p	22.7	12.2	1083	73

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, but the G3 provides a faster frame rate than the D3100. It can shoot movie footage at 1080/60i, while the Nikon is limited to 1080/24p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the G3 has an electronic viewfinder (1440k dots), while the D3100 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 viewfinder in the G3 offers a wider field of view (100%) than the one in the D3100 (95%), so that a larger proportion of the captured image is visible in the finder. In addition, the viewfinder of the G3 has a higher magnification (0.70x vs 0.53x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The table below summarizes some of the other core capabilities of the Nikon D3100 and Panasonic G3 in connection with corresponding information for a sample of similar 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.		Nikon D3100	optical	n	3.0 / 230	fixed	n	1/4000s	3.0/s	Y	n
2.		Panasonic G3	1440	n	3.0 / 460	swivel	Y	1/4000s	4.0/s	Y	n
3.		Nikon D3200	optical	n	3.0 / 921	fixed	n	1/4000s	4.0/s	Y	n
4.		Nikon D5100	optical	n	3.0 / 921	swivel	n	1/4000s	4.0/s	Y	n
5.		Nikon D7000	optical	Y	3.0 / 921	fixed	n	1/8000s	6.0/s	Y	n
6.		Nikon D3000	optical	n	3.0 / 230	fixed	n	1/4000s	3.0/s	Y	n
7.		Nikon D5000	optical	n	2.7 / 230	full-flex	n	1/4000s	4.0/s	Y	n
8.		Nikon D60	optical	n	2.5 / 230	fixed	n	1/4000s	3.0/s	Y	n
9.		Nikon D40X	optical	n	2.5 / 230	fixed	n	1/4000s	3.0/s	Y	n
10.		Nikon D40	optical	n	2.5 / 230	fixed	n	1/4000s	2.5/s	Y	n
11.		Panasonic G6	1440	n	3.0 / 1036	swivel	Y	1/4000s	7.0/s	Y	n
12.		Panasonic G5	1440	n	3.0 / 920	swivel	Y	1/4000s	6.0/s	Y	n
13.		Panasonic GX1	optional	n	3.0 / 460	fixed	Y	1/4000s	4.2/s	Y	n
14.		Panasonic G2	1440	n	3.0 / 460	swivel	Y	1/4000s	2.6/s	Y	n
15.		Panasonic GH2	1534	n	3.0 / 460	swivel	n	1/4000s	3.0/s	Y	n
16.		Sony NEX-5N	optional	n	3.0 / 920	tilting	Y	1/4000s	10.0/s	n	n
17.		Sony NEX-C3	optional	n	3.0 / 920	tilting	n	1/4000s	5.5/s	n	n
Notes: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One differentiating feature between the two cameras concerns the touch sensitivity of the rear screen. The G3 has a touchscreen, while the D3100 has a conventional panel. Touch control can be particularly helpful, for example, for setting the focus point.

Concerning the storage of imaging data, both the D3100 and the G3 write their files to SDXC 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 Nikon D3100 and Panasonic Lumix DMC-G3 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 D3100	Y	mono / mono	-	-	mini	2.0	-	-	-
2.		Panasonic G3	Y	stereo / mono	-	-	mini	2.0	-	-	-
3.		Nikon D3200	Y	mono / mono	Y	-	mini	2.0	-	-	-
4.		Nikon D5100	Y	mono / mono	Y	-	mini	2.0	-	-	-
5.		Nikon D7000	Y	mono / mono	Y	-	mini	2.0	-	-	-
6.		Nikon D3000	Y	- / -	-	-	-	2.0	-	-	-
7.		Nikon D5000	Y	mono / mono	-	-	mini	2.0	-	-	-
8.		Nikon D60	Y	- / -	-	-	-	2.0	-	-	-
9.		Nikon D40X	Y	- / -	-	-	-	2.0	-	-	-
10.		Nikon D40	Y	- / -	-	-	-	2.0	-	-	-
11.		Panasonic G6	Y	stereo / mono	Y	-	mini	2.0	Y	Y	-
12.		Panasonic G5	Y	stereo / mono	-	-	mini	2.0	-	-	-
13.		Panasonic GX1	Y	stereo / mono	-	-	mini	2.0	-	-	-
14.		Panasonic G2	Y	stereo / mono	-	-	mini	2.0	-	-	-
15.		Panasonic GH2	Y	stereo / mono	Y	-	mini	2.0	-	-	-
16.		Sony NEX-5N	Y	stereo / mono	-	-	mini	2.0	-	-	-
17.		Sony NEX-C3	Y	stereo / mono	-	-	mini	2.0	-	-	-

Both the D3100 and the G3 have been discontinued, but can regularly be found used on ebay. The D3100 was replaced by the Nikon D3200, while the G3 was followed by the Panasonic G5. Further information on the features and operation of the D3100 and G3 can be found, respectively, in the Nikon D3100 Manual (free pdf) or the online Panasonic G3 Manual.

Review summary

So what is the bottom line? Is there a clear favorite between the Nikon D3100 and the Panasonic G3? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.

Advantages of the Nikon D3100:

• Better image quality: Scores substantially higher (11 points) in the DXO overall assessment.
• Richer colors: Generates images with noticeably better colors (1.5 bits more color depth).
• More dynamic range: Captures a larger spectrum of light and dark details (0.7 EV of extra DR).
• Better low-light sensitivity: Requires less light for good images (0.5 stops ISO advantage).
• Brighter framing: Features an optical viewfinder for clear, lag-free composition.
• Longer lasting: Can take more shots (550 versus 270) on a single battery charge.
• More heavily discounted: Has been on the market for longer (launched in August 2010).

Reasons to prefer the Panasonic Lumix DMC-G3:

• Better video: Provides higher movie framerates (1080/60i versus 1080/24p).
• More framing info: Has an electronic viewfinder that displays shooting data.
• More complete view: Has a viewfinder with a larger field of view (100% vs 95%).
• Larger viewfinder image: Features a viewfinder with a higher magnification (0.70x vs 0.53x).
• More detailed LCD: Has a higher resolution rear screen (460k vs 230k dots).
• More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
• Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
• More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
• Faster burst: Shoots at higher frequency (4 vs 3 flaps/sec) to capture the decisive moment.
• More compact: Is smaller (115x84mm vs 124x96mm) and will fit more readily into a bag.
• Less heavy: Has a lower weight (by 169g or 33 percent) and is thus easier to take along.
• More legacy lens friendly: Can use many non-native lenses via adapters.
• More modern: Was introduced somewhat (8 months) more recently.

If the count of relative strengths (bullet points above) is taken as a measure, the G3 is the clear winner of the contest (13 : 7 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 sports photographer will view the differences between cameras in a way that diverges from the perspective of a street photog, and a person interested in family portraits has distinct needs from a landscape 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 D3100 and the Panasonic G3 place the cameras among the top in their class? Find out in the latest Best DSLR Camera and Best Mirrorless Interchangeable Lens 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 remains incomplete and does no justice, for example, to the way the D3100 or the G3 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 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.		Nikon D3100	5/5	+ +	..	72/100	4.5/5	4.5/5	Aug 2010	599	ebay.com
2.		Panasonic G3	3/5	+ +	..	75/100	4.5/5	5/5	May 2011	599	ebay.com
3.		Nikon D3200	5/5	+ +	..	73/100	4.5/5	4.5/5	Apr 2012	599	ebay.com
4.		Nikon D5100	5/5	+ +	..	76/100	4.5/5	4.5/5	Apr 2011	749	ebay.com
5.		Nikon D7000	4/5	..	..	80/100	4.5/5	4.5/5	Sep 2010	1,499	ebay.com
6.		Nikon D3000	..	+	..	72/100	4/5	4.5/5	Jul 2009	599	ebay.com
7.		Nikon D5000	..	+ +	..	75/100	4/5	4.5/5	Apr 2009	749	ebay.com
8.		Nikon D60	..	80/100	..	+ +	4/5	4.5/5	Jan 2008	629	ebay.com
9.		Nikon D40X	..	79/100	..	+ +	4/5	4/5	Mar 2007	729	ebay.com
10.		Nikon D40	..	81/100	..	+ +	o	4.5/5	Nov 2006	499	ebay.com
11.		Panasonic G6	4/5	+ +	..	..	5/5	4.5/5	Apr 2013	599	ebay.com
12.		Panasonic G5	3/5	+ +	..	..	4.5/5	4.5/5	Jul 2012	599	ebay.com
13.		Panasonic GX1	3/5	+	..	77/100	4.5/5	4.5/5	Nov 2011	699	ebay.com
14.		Panasonic G2	..	..	..	72/100	4/5	4.5/5	Mar 2010	599	ebay.com
15.		Panasonic GH2	5/5	+ +	..	79/100	4.5/5	5/5	Sep 2010	899	ebay.com
16.		Sony NEX-5N	3/5	+ +	..	79/100	4.5/5	4.5/5	Aug 2011	699	ebay.com
17.		Sony NEX-C3	3/5	+ +	..	74/100	4.5/5	4/5	Jun 2011	599	ebay.com
Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The review scores listed above should be treated with care, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. 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, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

Check D3100 offers at
ebay.com
Check G3 offers at
ebay.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.

~

Check D3100 offers at
ebay.com
Check G3 offers at
ebay.com

Did you notice an error on this page? If so, please get in touch, so that we can correct the information.