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Nikon D90 vs Olympus E-520

The Nikon D90 and the Olympus E-520 are two digital cameras that were officially introduced, respectively, in August 2008 and May 2008. Both are DSLR (Digital Single Lens Reflex) cameras that are based on an APS-C (D90) and a Four Thirds (E-520) sensor. The Nikon has a resolution of 12.2 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
Nikon D90
versus
Olympus E-520
Nikon D90   Olympus E-520
Digital single lens reflex Digital single lens reflex
Nikon F mount lenses Four Thirds lenses
12.2 MP – APS-C sensor 10 MP – Four Thirds sensor
720/24p Video no Video
ISO 200-3,200 (200 - 6,400) ISO 100-1,600
Optical viewfinder Optical viewfinder
3.0" LCD – 920k dots 3.0" LCD – 215k dots
Fixed screen (not touch-sensitive) Fixed screen (not touch-sensitive)
4.5 shutter flaps per second 3.5 shutter flaps per second
Lens stabilization onlyIn-body stabilization
850 shots per battery charge750 shots per battery charge
132 x 103 x 77 mm, 703 g 136 x 92 x 68 mm, 535 g
Nikon D90:
Check Ebay offers
Olympus E-520:
Check Ebay offers

Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon D90 and the Olympus E-520? 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 D90 and the Olympus E-520. 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 measures are rounded to the nearest millimeter.

Size Nikon D90 vs Olympus E-520
Compare D90 versus E-520 top
Comparison D90 or E-520 rear

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Olympus E-520 is notably smaller (8 percent) than the Nikon D90. Moreover, the E-520 is markedly lighter (24 percent) than the D90. In this context, it is worth noting that neither the D90 nor the E-520 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 (D90) and the Four Thirds Lens Catalog (E-520).

Concerning battery life, the D90 gets 850 shots out of its EN-EL3e battery, while the E-520 can take 750 images on a single charge of its BLM-1 power pack.

The following table provides a synthesis of the main physical specifications of the two cameras and other similar ones. 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.

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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 D90 132 mm 103 mm 77 mm 703 g 850 n Aug 2008 1,299i
2.
 
Olympus E-520 136 mm 92 mm 68 mm 535 g 750 n May 2008 699i
3.
 
Canon 40D 146 mm 108 mm 74 mm 822 g 750 n Aug 2007 1,299i
4.
 
Nikon D7000 132 mm 105 mm 77 mm 780 g 1050 Y Sep 2010 1,499i
5.
 
Nikon D3100 124 mm 96 mm 75 mm 505 g 550 n Aug 2010 599i
6.
 
Nikon D300S 147 mm 115 mm 81 mm 938 g 950 Y Jul 2009 1,799i
7.
 
Nikon D3000 126 mm 97 mm 64 mm 536 g 500 n Jul 2009 599i
8.
 
Nikon D5000 127 mm 104 mm 80 mm 590 g 510 n Apr 2009 749i
9.
 
Nikon D60 126 mm 94 mm 64 mm 522 g 500 n Jan 2008 629i
10.
 
Nikon D40X 124 mm 94 mm 64 mm 522 g 520 n Mar 2007 729i
11.
 
Nikon D300 147 mm 114 mm 74 mm 925 g 1000 Y Aug 2007 1,799i
12.
 
Nikon D80 132 mm 103 mm 77 mm 668 g 600 n Aug 2006 999i
13.
 
Olympus E-600 130 mm 94 mm 60 mm 535 g 500 n Aug 2009 449i
14.
 
Olympus E-620 130 mm 94 mm 60 mm 521 g 500 n Feb 2009 699i
15.
 
Olympus E-420 130 mm 91 mm 53 mm 440 g 500 n Mar 2008 599i
16.
 
Olympus E-410 130 mm 91 mm 53 mm 435 g 500 n Mar 2007 699i
17.
 
Olympus E-510 136 mm 92 mm 68 mm 538 g 750 n Mar 2007 799i
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.

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-520 was launched at a markedly lower price (by 46 percent) than the D90, 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. 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 tend to be associated with larger, more expensive camera bodies and lenses.

Of the two cameras under consideration, the Nikon D90 features an APS-C sensor and the Olympus E-520 a Four Thirds sensor. The sensor area in the E-520 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 D90 has a native 3:2 aspect ratio, while the one in the E-520 offers a 4:3 aspect.

Nikon D90 and Olympus E-520 sensor measures

With 12.2MP, the D90 offers a higher resolution than the E-520 (10MP), but the D90 nevertheless has larger individual pixels (pixel pitch of 5.53μm versus 4.74μm for the E-520) due to its larger sensor. Moreover, the D90 is a somewhat more recent model (by 3 months) than the E-520, and its sensor might have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixels.

The resolution advantage of the Nikon D90 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the D90 for good quality output (200 dots per inch) amounts to 21.4 x 14.2 inches or 54.5 x 36.2 cm, for very good quality (250 dpi) 17.2 x 11.4 inches or 43.6 x 28.9 cm, and for excellent quality (300 dpi) 14.3 x 9.5 inches or 36.3 x 24.1 cm. The corresponding values for the Olympus E-520 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 Nikon D90 has a native sensitivity range from ISO 200 to ISO 3200, which can be extended to ISO 200-6400. The corresponding ISO settings for the Olympus E-520 are ISO 100 to ISO 1600 (no boost).

D90 versus E-520 MP

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. Of the two cameras under review, the D90 provides substantially higher image quality than the E-520, with an overall score that is 18 points higher. This advantage is based on 1.3 bits higher color depth, 2.1 EV in additional dynamic range, and 0.8 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.

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Sensor Characteristics
    Camera
Model
Sensor
Class
Resolution
(MP)
Horiz.
Pixels
Vert.
Pixels
Video
Format
DXO
Portrait
DXO
Landscape
DXO
Sports
DXO
Overall
1.
 
Nikon D90 APS-C 12.2 4288 2848720/24p22.712.597773
2.
 
Olympus E-520 Four Thirds 10.0 3648 2736none21.410.454855
3.
 
Canon 40D APS-C 10.1 3888 2592none22.111.370364
4.
 
Nikon D7000 APS-C 16.1 4928 32641080/24p23.513.9116780
5.
 
Nikon D3100 APS-C 14.2 4608 30721080/24p22.511.391967
6.
 
Nikon D300S APS-C 12.2 4288 2848720/24p22.512.278770
7.
 
Nikon D3000 APS-C 10.0 3872 2592none22.311.156362
8.
 
Nikon D5000 APS-C 12.2 4288 2848720/24p22.712.586872
9.
 
Nikon D60 APS-C 10.0 3872 2592none22.511.456265
10.
 
Nikon D40X APS-C 10.0 3872 2592none22.411.451663
11.
 
Nikon D300 APS-C 12.2 4288 2848none22.112.067967
12.
 
Nikon D80 APS-C 10.0 3872 2592none22.111.252461
13.
 
Olympus E-600 Four Thirds 12.2 4032 3024none21.510.354155
14.
 
Olympus E-620 Four Thirds 12.2 4032 3024none21.310.353655
15.
 
Olympus E-420 Four Thirds 10.0 3648 2736none21.510.452756
16.
 
Olympus E-410 Four Thirds 10.0 3648 2736none21.110.049451
17.
 
Olympus E-510 Four Thirds 10.0 3648 2736none21.210.044252

Many modern cameras cannot only take still pictures, but also record videos. The D90 indeed provides movie recording capabilities, while the E-520 does not. The highest resolution format that the D90 can use is 720/24p.

Feature comparison

Apart from body and sensor, cameras can and do differ across a variety of features. The D90 and the E-520 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 D90 offers a wider field of view (96%) than the one in the E-520 (95%), so that a larger proportion of the captured image is visible in the finder. In addition, the viewfinder of the D90 has a higher magnification (0.63x 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 Nikon D90 and Olympus E-520 in connection with corresponding information for a sample of similar cameras.

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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 D90optical Y3.0 / 920 fixed n 1/4000s 4.5/s Y n
2.
 
Olympus E-520optical n2.7 / 215 fixed n 1/4000s 3.5/s Y Y
3.
 
Canon 40Doptical Y3.0 / 230 fixed n 1/8000s 6.5/s Y n
4.
 
Nikon D7000optical Y3.0 / 921 fixed n 1/8000s 6.0/s Y n
5.
 
Nikon D3100optical n3.0 / 230 fixed n 1/4000s 3.0/s Y n
6.
 
Nikon D300Soptical Y3.0 / 920 fixed n 1/8000s 7.0/s Y n
7.
 
Nikon D3000optical n3.0 / 230 fixed n 1/4000s 3.0/s Y n
8.
 
Nikon D5000optical n2.7 / 230 full-flex n 1/4000s 4.0/s Y n
9.
 
Nikon D60optical n2.5 / 230 fixed n 1/4000s 3.0/s Y n
10.
 
Nikon D40Xoptical n2.5 / 230 fixed n 1/4000s 3.0/s Y n
11.
 
Nikon D300optical Y3.0 / 922 fixed n 1/8000s 6.0/s Y n
12.
 
Nikon D80optical n2.5 / 230 fixed n 1/4000s 3.0/s Y n
13.
 
Olympus E-600optical n2.7 / 230 swivel n 1/4000s 4.0/s Y Y
14.
 
Olympus E-620optical n2.7 / 230 swivel n 1/4000s 4.0/s Y Y
15.
 
Olympus E-420optical n2.7 / 215 fixed n 1/4000s 3.5/s Y n
16.
 
Olympus E-410optical n2.5 / 215 fixed n 1/4000s 3.0/s Y n
17.
 
Olympus E-510optical n2.5 / 215 fixed n 1/4000s 3.0/s Y Y
Notes: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.

One feature that is present on the D90, but is missing on the E-520 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 D90 writes its imaging data to SDHC cards, while the E-520 uses Compact Flash or xD Picture cards. The E-520 features dual card slots, which can be very useful in case a memory card fails. In contrast, the D90 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 Nikon D90 and Olympus E-520 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

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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 D90Ymono / mono--mini2.0---
2.
 
Olympus E-520Y- / ----2.0---
3.
 
Canon 40DY- / ----2.0---
4.
 
Nikon D7000Ymono / monoY-mini2.0---
5.
 
Nikon D3100Ymono / mono--mini2.0---
6.
 
Nikon D300SYstereo / monoY-mini2.0---
7.
 
Nikon D3000Y- / ----2.0---
8.
 
Nikon D5000Ymono / mono--mini2.0---
9.
 
Nikon D60Y- / ----2.0---
10.
 
Nikon D40XY- / ----2.0---
11.
 
Nikon D300Y- / ---mini2.0---
12.
 
Nikon D80Y- / ----2.0---
13.
 
Olympus E-600Y- / ----2.0---
14.
 
Olympus E-620Y- / ----2.0---
15.
 
Olympus E-420Y- / ----2.0---
16.
 
Olympus E-410Y- / ----2.0---
17.
 
Olympus E-510Y- / ----2.0---

Both the D90 and the E-520 have been discontinued, but can regularly be found used on eBay. The D90 was replaced by the Nikon D7000, while the E-520 does not have a direct successor. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Nikon and Olympus websites.

Review summary

So how do things add up? Is there a clear favorite between the Nikon D90 and the Olympus E-520? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.

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Reasons to prefer the Nikon D90:

  • More detail: Offers more megapixels (12.2 vs 10MP) with a 13% higher linear resolution.
  • Better image quality: Scores substantially higher (18 points) in the DXO overall assessment.
  • Richer colors: Generates images with noticeably better colors (1.3 bits more color depth).
  • More dynamic range: Captures a larger spectrum of light and dark details (2.1 EV of extra DR).
  • Better low-light sensitivity: Requires less light for good images (0.8 stops ISO advantage).
  • Broader imaging potential: Can record not only still images but also 720/24p movies.
  • More complete view: Has a viewfinder with a larger field of view (96% vs 95%).
  • Larger viewfinder image: Features a viewfinder with a higher magnification (0.63x 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 (920k vs 215k dots).
  • Faster burst: Shoots at higher frequency (4.5 vs 3.5 flaps/sec) to capture the decisive moment.
  • Longer lasting: Can take more shots (850 versus 750) on a single battery charge.
  • More modern: Is somewhat more recent (announced 3 months after the E-520).

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Advantages of the Olympus E-520:

  • Less heavy: Has a lower weight (by 168g or 24 percent) and is thus easier to take along.
  • Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
  • 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 (46 percent cheaper at launch).
  • More heavily discounted: Has been on the market for longer (launched in May 2008).

If the number of relative strengths (bullet points above) is taken as a guide, the D90 is the clear winner of the match-up (14 : 5 points). However, the relevance of individual strengths will vary across photographers, so that you might want to apply your own weighing scheme to the summary points when reflecting and deciding on a new camera. 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.

D90 14:05 E-520

How about other alternatives? Do the specifications of the Nikon D90 and the Olympus E-520 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 remains incomplete and does no justice, for example, to the way the D90 or the E-520 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 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.

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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 D90..+ +..+ +4/54.5/5 Aug 2008 1,299i
2.
 
Olympus E-520..87/100..+ +4.5/54.5/5 May 2008 699i
3.
 
Canon 40D..+ +..+ +4.5/54.5/5 Aug 2007 1,299i
4.
 
Nikon D70004/5....80/1004.5/54.5/5 Sep 2010 1,499i
5.
 
Nikon D31005/5+ +..72/1004.5/54.5/5 Aug 2010 599i
6.
 
Nikon D300S5/5+ +..82/1004/54.5/5 Jul 2009 1,799i
7.
 
Nikon D3000..+..72/1004/54.5/5 Jul 2009 599i
8.
 
Nikon D5000..+ +..75/1004/54.5/5 Apr 2009 749i
9.
 
Nikon D60..80/100..+ +4/54.5/5 Jan 2008 629i
10.
 
Nikon D40X..79/100..+ +4/54/5 Mar 2007 729i
11.
 
Nikon D300..+ +..+ +5/54.5/5 Aug 2007 1,799i
12.
 
Nikon D80..+..+ +o4.5/5 Aug 2006 999i
13.
 
Olympus E-600..........4.5/5 Aug 2009 449i
14.
 
Olympus E-6203/588/100..72/1004.5/55/5 Feb 2009 699i
15.
 
Olympus E-420..85/100..+ +4/54.5/5 Mar 2008 599i
16.
 
Olympus E-410..86/100..+ +4/54.5/5 Mar 2007 699i
17.
 
Olympus E-510..89/100..+ +3.5/54.5/5 Mar 2007 799i
Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

Care should be taken when interpreting the review scores above, 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 rating-comparisons among cameras that span long time periods or concern very differently equipped models make little sense. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

Nikon D90:
Check Ebay offers
Olympus E-520:
Check Ebay offers

Other camera comparisons

Did this review help to inform your camera decision process? In case you would like to check on the differences and similarities of other camera models, just use the search menu 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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    Specifications: Nikon D90 vs Olympus E-520

    Below is a side-by-side comparison of the specs of the two cameras to facilitate a quick review of their differences and common features.

    Camera Specifications
    Camera Model Nikon D90 Olympus E-520
    Camera Type Digital single lens reflex Digital single lens reflex
    Camera Lens Nikon F mount lenses Four Thirds lenses
    Launch Date August 2008 May 2008
    Launch Price USD 1,299 USD 699
    Sensor Specs Nikon D90 Olympus E-520
    Sensor Technology CMOS CMOS
    Sensor Format APS-C Sensor Four Thirds Sensor
    Sensor Size 23.6 x 15.8 mm 17.3 x 13.0 mm
    Sensor Area 372.88 mm2 224.9 mm2
    Sensor Diagonal 28.4 mm 21.6 mm
    Crop Factor 1.5x 2.0x
    Sensor Resolution 12.2 Megapixels 10 Megapixels
    Image Resolution 4288 x 2848 pixels 3648 x 2736 pixels
    Pixel Pitch 5.53 μm 4.74 μm
    Pixel Density 3.28 MP/cm2 4.44 MP/cm2
    Moiré control Anti-Alias filter Anti-Alias filter
    Movie Capability 720/24p Video no Video
    ISO Setting 200 - 3,200 ISO 100 - 1,600 ISO
    ISO Boost 200 - 6,400 ISO no Enhancement
    Image Processor EXPEED TruePic III
    DXO Sensor Quality (score) 73 55
    DXO Color Depth (bits) 22.7 21.4
    DXO Dynamic Range (EV) 12.5 10.4
    DXO Low Light (ISO) 977 548
    Screen Specs Nikon D90 Olympus E-520
    Viewfinder Type Optical viewfinder Optical viewfinder
    Viewfinder Field of View 96% 95%
    Viewfinder Magnification 0.63x 0.46x
    Top-Level Screen Control Panel no Top Display
    LCD Framing Live View Live View
    Rear LCD Size 3.0inch 2.7inch
    LCD Resolution 920k dots 215k dots
    LCD Attachment Fixed screen Fixed screen
    Shooting Specs Nikon D90 Olympus E-520
    Focus System Phase-detect AF Phase-detect AF
    Continuous Shooting 4.5 shutter flaps/s 3.5 shutter flaps/s
    Image StabilizationLens stabilization onlyIn-body stabilization
    Fill Flash Built-in Flash Built-in Flash
    Storage Medium SDHC cards CF or XD cards
    Second Storage Option Single card slot Dual card slots
    Connectivity Specs Nikon D90 Olympus E-520
    External Flash Hotshoe Hotshoe
    USB Connector USB 2.0 USB 2.0
    HDMI Port mini HDMI no HDMI
    Wifi Support no Wifi no Wifi
    Body Specs Nikon D90 Olympus E-520
    Battery Type EN-EL3e BLM-1
    Battery Life (CIPA)850 shots per charge750 shots per charge
    Body Dimensions 132 x 103 x 77 mm
    (5.2 x 4.1 x 3.0 in)
    136 x 92 x 68 mm
    (5.4 x 3.6 x 2.7 in)
    Camera Weight 703 g (24.8 oz) 535 g (18.9 oz)
    Nikon D90:
    Check Ebay offers
    Olympus E-520:
    Check Ebay offers

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