Pentax K-5 vs Olympus E-420

The Pentax K-5 and the Olympus E-420 are two digital cameras that were revealed to the public, respectively, in September 2010 and March 2008. Both are DSLR (Digital Single Lens Reflex) cameras that are based on an APS-C (K-5) and a Four Thirds (E-420) sensor. The Pentax has a resolution of 16.1 megapixels, whereas the Olympus provides 10 MP.

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

Headline Specifications

Pentax K-5		Olympus E-420
Digital single lens reflex		Digital single lens reflex
Pentax K mount lenses		Four Thirds lenses
16.1 MP – APS-C sensor		10 MP – Four Thirds sensor
1080/25p Video		no Video
ISO 100-12,800 (80 - 51,200)		ISO 100-1,600
Optical viewfinder		Optical viewfinder
3.0" LCD – 921k dots		2.7" LCD – 215k dots
Fixed screen (not touch-sensitive)		Fixed screen (not touch-sensitive)
7 shutter flaps per second		3.5 shutter flaps per second
In-body stabilization		Lens stabilization only
Weathersealed body		not weather sealed
740 shots per battery charge		500 shots per battery charge
131 x 97 x 73 mm, 760 g		130 x 91 x 53 mm, 440 g

Check K-5 offers at
ebay.com
Check E-420 offers at
ebay.com

Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-5 and the Olympus E-420? 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-5 and the Olympus E-420. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All size 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 Olympus E-420 is notably smaller (7 percent) than the Pentax K-5. Moreover, the E-420 is substantially lighter (42 percent) than the K-5. It is worth mentioning in this context that the K-5 is splash and dust resistant, while the E-420 does not feature any corresponding weather-sealing.

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-5 gets 740 shots out of its Pentax D-LI90 battery, while the E-420 can take 500 images on a single charge of its Olympus BLS-1 power pack.

The adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. 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 (USD)	Street Price
1.		Pentax K-5	131 mm	97 mm	73 mm	760 g	740	Y	Sep 2010	1,099	ebay.com
2.		Olympus E-420	130 mm	91 mm	53 mm	440 g	500	n	Mar 2008	599	ebay.com
3.		Nikon D7000	132 mm	105 mm	77 mm	780 g	1050	Y	Sep 2010	1,499	ebay.com
4.		Olympus E-450	130 mm	91 mm	53 mm	440 g	500	n	Mar 2009	499	ebay.com
5.		Olympus E-620	130 mm	94 mm	60 mm	521 g	500	n	Feb 2009	699	ebay.com
6.		Olympus E-520	136 mm	92 mm	68 mm	535 g	750	n	May 2008	699	ebay.com
7.		Olympus E-410	130 mm	91 mm	53 mm	435 g	500	n	Mar 2007	699	ebay.com
8.		Olympus E-400	130 mm	91 mm	53 mm	435 g	500	n	Sep 2006	699	ebay.com
9.		Pentax KP	132 mm	101 mm	76 mm	703 g	390	Y	Jan 2017	1,099	ebay.com
10.		Pentax K-70	126 mm	93 mm	74 mm	688 g	410	Y	Jun 2016	649	ebay.com
11.		Pentax K-3 II	131 mm	100 mm	77 mm	800 g	720	Y	Apr 2015	1,099	ebay.com
12.		Pentax K-50	130 mm	97 mm	71 mm	650 g	410	Y	Jun 2013	599	ebay.com
13.		Pentax K-500	130 mm	97 mm	71 mm	646 g	710	n	Jun 2013	549	ebay.com
14.		Pentax K-3	131 mm	100 mm	77 mm	800 g	560	Y	Oct 2013	1,299	ebay.com
15.		Pentax K-30	130 mm	97 mm	71 mm	650 g	410	Y	May 2012	849	ebay.com
16.		Pentax K-5 II	131 mm	97 mm	73 mm	760 g	740	Y	Sep 2012	1,099	ebay.com
17.		Sony A77	143 mm	104 mm	81 mm	732 g	470	Y	Aug 2011	1,399	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 naturally be influenced heavily by the price. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The E-420 was launched at a markedly lower price (by 45 percent) than the K-5, 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.

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 tend to be more expensive and lead to bigger and heavier cameras and lenses.

Of the two cameras under consideration, the Pentax K-5 features an APS-C sensor and the Olympus E-420 a Four Thirds sensor. The sensor area in the E-420 is 40 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 K-5 has a native 3:2 aspect ratio, while the one in the E-420 offers a 4:3 aspect.

With 16.1MP, the K-5 offers a higher resolution than the E-420 (10MP), but the K-5 nevertheless has marginally larger individual pixels (pixel pitch of 4.81μm versus 4.74μm for the E-420) due to its larger sensor. Moreover, the K-5 is a much more recent model (by 2 years and 6 months) than the E-420, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixels.

The resolution advantage of the Pentax K-5 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-5 for good quality output (200 dots per inch) amounts to 24.6 x 16.3 inches or 62.6 x 41.5 cm, for very good quality (250 dpi) 19.7 x 13.1 inches or 50.1 x 33.2 cm, and for excellent quality (300 dpi) 16.4 x 10.9 inches or 41.7 x 27.6 cm. The corresponding values for the Olympus E-420 are 18.2 x 13.7 inches or 46.3 x 34.7 cm for good quality, 14.6 x 10.9 inches or 37.1 x 27.8 cm for very good quality, and 12.2 x 9.1 inches or 30.9 x 23.2 cm for excellent quality prints.

The Pentax K-5 has a native sensitivity range from ISO 100 to ISO 12800, which can be extended to ISO 80-51200. The corresponding ISO settings for the Olympus E-420 are ISO 100 to ISO 1600 (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.

Consistent information on actual sensor performance is available from DXO Mark for many cameras. This service determines an overall sensor rating, as well as sub-scores for low-light sensitivity ("DXO Sports"), dynamic range ("DXO Landscape"), and color depth ("DXO Portrait"). Of the two cameras under review, the K-5 provides substantially higher image quality than the E-420, with an overall score that is 26 points higher. This advantage is based on 2.2 bits higher color depth, 3.7 EV in additional dynamic range, and 1.1 stops in additional low light sensitivity. 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.		Pentax K-5	APS-C	16.1	4928	3264	1080/25p	23.7	14.1	1162	82
2.		Olympus E-420	Four Thirds	10.0	3648	2736	none	21.5	10.4	527	56
3.		Nikon D7000	APS-C	16.1	4928	3264	1080/24p	23.5	13.9	1167	80
4.		Olympus E-450	Four Thirds	10.0	3648	2736	none	21.5	10.5	512	56
5.		Olympus E-620	Four Thirds	12.2	4032	3024	none	21.3	10.3	536	55
6.		Olympus E-520	Four Thirds	10.0	3648	2736	none	21.4	10.4	548	55
7.		Olympus E-410	Four Thirds	10.0	3648	2736	none	21.1	10.0	494	51
8.		Olympus E-400	Four Thirds	10.0	3648	2736	none	21.0	10.6	127	53
9.		Pentax KP	APS-C	24.1	6016	4000	1080/60i	23.9	13.2	1699	81
10.		Pentax K-70	APS-C	24.0	6000	4000	1080/60i	23.8	13.1	1639	80
11.		Pentax K-3 II	APS-C	24.1	6016	4000	1080/60i	23.6	13.6	1106	80
12.		Pentax K-50	APS-C	16.1	4928	3264	1080/30p	23.7	13.0	1120	79
13.		Pentax K-500	APS-C	16.1	4928	3264	1080/30p	23.7	13.1	1087	79
14.		Pentax K-3	APS-C	24.1	6016	4000	1080/60i	23.7	13.4	1216	80
15.		Pentax K-30	APS-C	16.1	4928	3264	1080/30p	23.7	13.0	1129	79
16.		Pentax K-5 II	APS-C	16.1	4928	3264	1080/25p	23.8	14.1	1235	82
17.		Sony A77	APS-C	24.0	6000	4000	1080/60p	24.0	13.2	801	78
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 K-5 indeed provides movie recording capabilities, while the E-420 does not. The highest resolution format that the K-5 can use is 1080/25p.

Feature comparison

Apart from body and sensor, cameras can and do differ across a range of features. The K-5 and the E-420 are similar in the sense that both have an optical viewfinder. The latter is useful for getting a clear image for framing even in brightly lit environments. The viewfinder in the K-5 offers a wider field of view (100%) than the one in the E-420 (95%), so that a larger proportion of the captured image is visible in the finder. In addition, the viewfinder of the K-5 has a higher magnification (0.61x vs 0.46x), 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 Pentax K-5 and Olympus E-420 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.		Pentax K-5	optical	Y	3.0 / 921	fixed	n	1/8000s	7.0/s	Y	Y
2.		Olympus E-420	optical	n	2.7 / 215	fixed	n	1/4000s	3.5/s	Y	n
3.		Nikon D7000	optical	Y	3.0 / 921	fixed	n	1/8000s	6.0/s	Y	n
4.		Olympus E-450	optical	n	2.7 / 215	fixed	n	1/4000s	3.5/s	Y	n
5.		Olympus E-620	optical	n	2.7 / 230	swivel	n	1/4000s	4.0/s	Y	Y
6.		Olympus E-520	optical	n	2.7 / 215	fixed	n	1/4000s	3.5/s	Y	Y
7.		Olympus E-410	optical	n	2.5 / 215	fixed	n	1/4000s	3.0/s	Y	n
8.		Olympus E-400	optical	n	2.5 / 215	fixed	n	1/4000s	3.0/s	Y	n
9.		Pentax KP	optical	n	3.0 / 921	tilting	n	1/6000s	7.0/s	Y	Y
10.		Pentax K-70	optical	n	3.0 / 921	swivel	n	1/6000s	6.0/s	Y	Y
11.		Pentax K-3 II	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	n	Y
12.		Pentax K-50	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
13.		Pentax K-500	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
14.		Pentax K-3	optical	Y	3.2 / 1037	fixed	n	1/8000s	8.3/s	Y	Y
15.		Pentax K-30	optical	n	3.0 / 921	fixed	n	1/6000s	6.0/s	Y	Y
16.		Pentax K-5 II	optical	Y	3.0 / 921	fixed	n	1/8000s	7.0/s	Y	Y
17.		Sony A77	2359	Y	3.0 / 921	full-flex	n	1/8000s	12.0/s	Y	Y
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One feature that is present on the K-5, but is missing on the E-420 is a top-level LCD. While being, of course, smaller than the rear screen, the control panel conveys some of the essential shooting information and can be convenient for quick and easy settings verification.

The Pentax K-5 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-5 writes its imaging data to SDXC cards, while the E-420 uses Compact Flash or xD Picture cards. The E-420 features dual card slots, which can be very useful in case a memory card fails. In contrast, the K-5 only has one slot.

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-5 and Olympus E-420 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-5	Y	stereo / mono	Y	-	mini	2.0	-	-	-
2.		Olympus E-420	Y	- / -	-	-	-	2.0	-	-	-
3.		Nikon D7000	Y	mono / mono	Y	-	mini	2.0	-	-	-
4.		Olympus E-450	Y	- / -	-	-	-	2.0	-	-	-
5.		Olympus E-620	Y	- / -	-	-	-	2.0	-	-	-
6.		Olympus E-520	Y	- / -	-	-	-	2.0	-	-	-
7.		Olympus E-410	Y	- / -	-	-	-	2.0	-	-	-
8.		Olympus E-400	Y	- / -	-	-	-	2.0	-	-	-
9.		Pentax KP	Y	stereo / mono	Y	-	-	2.0	Y	-	-
10.		Pentax K-70	Y	stereo / mono	Y	-	mini	2.0	Y	-	-
11.		Pentax K-3 II	Y	mono / mono	Y	Y	mini	3.0	-	-	-
12.		Pentax K-50	Y	mono / mono	-	-	micro	2.0	-	-	-
13.		Pentax K-500	Y	mono / mono	-	-	-	2.0	-	-	-
14.		Pentax K-3	Y	mono / mono	Y	Y	mini	3.0	-	-	-
15.		Pentax K-30	Y	mono / mono	-	-	-	2.0	-	-	-
16.		Pentax K-5 II	Y	stereo / mono	Y	-	mini	2.0	-	-	-
17.		Sony A77	Y	stereo / mono	Y	-	mini	2.0	-	-	-

Studio photographers will appreciate that the Pentax K-5 (unlike the E-420) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Both the K-5 and the E-420 have been discontinued, but can regularly be found used on ebay. The K-5 was replaced by the Pentax K-5 II, while the E-420 does not have a direct successor. Further information on the features and operation of the K-5 and E-420 can be found, respectively, in the Pentax K-5 Manual (free pdf) or the online Olympus E-420 Manual.

Review summary

So what conclusions can be drawn? Which of the two cameras – the Pentax K-5 or the Olympus E-420 – 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.

Advantages of the Pentax K-5:

• More detail: Offers more megapixels (16.1 vs 10MP) with a 30% higher linear resolution.
• Better image quality: Scores substantially higher (26 points) in the DXO overall assessment.
• Richer colors: Generates images with noticeably better colors (2.2 bits more color depth).
• More dynamic range: Captures a larger spectrum of light and dark details (3.7 EV of extra DR).
• Better low-light sensitivity: Requires less light for good images (1.1 stops ISO advantage).
• Broader imaging potential: Can record not only still images but also 1080/25p movies.
• 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 (0.61x vs 0.46x).
• Easier setting verification: Features an LCD display on top to control shooting parameters.
• Larger screen: Has a bigger rear LCD (3.0" vs 2.7") for image review and settings control.
• More detailed LCD: Has a higher resolution rear screen (921k vs 215k dots).
• Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
• Faster burst: Shoots at higher frequency (7 vs 3.5 flaps/sec) to capture the decisive moment.
• Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
• Longer lasting: Can take more shots (740 versus 500) on a single battery charge.
• Better sealing: Is weather sealed to enable shooting in dusty or wet environments.
• Sharper images: Has hand-shake reducing image stabilization built-in.
• Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
• More modern: Reflects 2 years and 6 months of technical progress since the E-420 launch.

Reasons to prefer the Olympus E-420:

• Less heavy: Has a lower weight (by 320g or 42 percent) and is thus easier to take along.
• 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 category (45 percent cheaper at launch).
• More heavily discounted: Has been around for much longer (launched in March 2008).

If the number of relative strengths (bullet points above) is taken as a guide, the K-5 is the clear winner of the match-up (19 : 4 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 wedding photographer will view the differences between cameras in a way that diverges from the perspective of a travel photog, and a person interested in cityscapes has distinct needs from a macro 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-5 and the Olympus E-420 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 the spec-sheets of cameras can offer a general idea of their imaging potential, it says little about, for example, the shooting experience and imaging performance of the K-5 and the E-420 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 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 (USD)	Street Price
1.		Pentax K-5	4/5	..	..	83/100	5/5	4.5/5	Sep 2010	1,099	ebay.com
2.		Olympus E-420	..	85/100	..	+ +	4/5	4.5/5	Mar 2008	599	ebay.com
3.		Nikon D7000	4/5	..	..	80/100	4.5/5	4.5/5	Sep 2010	1,499	ebay.com
4.		Olympus E-450	..	..	..	..	4/5	4/5	Mar 2009	499	ebay.com
5.		Olympus E-620	3/5	88/100	..	72/100	4.5/5	5/5	Feb 2009	699	ebay.com
6.		Olympus E-520	..	87/100	..	+ +	4.5/5	4.5/5	May 2008	699	ebay.com
7.		Olympus E-410	..	86/100	..	+ +	4/5	4.5/5	Mar 2007	699	ebay.com
8.		Olympus E-400	..	85/100	..	..	4/5	4/5	Sep 2006	699	ebay.com
9.		Pentax KP	4/5	..	3/5	82/100	5/5	4.5/5	Jan 2017	1,099	ebay.com
10.		Pentax K-70	4.5/5	..	4/5	79/100	4.5/5	4.5/5	Jun 2016	649	ebay.com
11.		Pentax K-3 II	4.5/5	..	..	..	5/5	5/5	Apr 2015	1,099	ebay.com
12.		Pentax K-50	5/5	..	..	..	5/5	4.5/5	Jun 2013	599	ebay.com
13.		Pentax K-500	..	..	..	..	4.5/5	4.5/5	Jun 2013	549	ebay.com
14.		Pentax K-3	4/5	..	..	83/100	5/5	5/5	Oct 2013	1,299	ebay.com
15.		Pentax K-30	4/5	..	..	78/100	4.5/5	4.5/5	May 2012	849	ebay.com
16.		Pentax K-5 II	5/5	..	..	80/100	5/5	4.5/5	Sep 2012	1,099	ebay.com
17.		Sony A77	5/5	91/100	..	81/100	..	5/5	Aug 2011	1,399	ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Care should be taken when interpreting the review scores above, 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. It should also be noted that some of the review sites have over time altered the way they render their verdicts.

Check K-5 offers at
ebay.com
Check E-420 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 use the search menu below. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.

~

Check K-5 offers at
ebay.com
Check E-420 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.