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Nikon D40 vs Canon 20D

The Nikon D40 and the Canon EOS 20D are two digital cameras that were officially introduced, respectively, in November 2006 and August 2004. Both are DSLR (Digital Single Lens Reflex) cameras that are equipped with an APS-C sensor. The Nikon has a resolution of 6 megapixels, whereas the Canon provides 8.2 MP.

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

Headline Specifications
Nikon D40
versus
Canon 20D
Nikon D40   Canon 20D
Digital single lens reflex Digital single lens reflex
Nikon F mount lenses Canon EF mount lenses
6 MP – APS-C sensor 8.2 MP – APS-C sensor
no Video no Video
ISO 200-1,600 (200 - 3,200) ISO 100-1,600 (100 - 3,200)
Optical viewfinder Optical viewfinder
2.5" LCD – 230k dots 1.8" LCD – 118k dots
Fixed screen (not touch-sensitive) Fixed screen (not touch-sensitive)
2.5 shutter flaps per second 5 shutter flaps per second
470 shots per battery charge700 shots per battery charge
124 x 94 x 64 mm, 522 g 144 x 106 x 72 mm, 770 g
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Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon D40 and the Canon EOS 20D? 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.

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Body comparison

An illustration of the physical size and weight of the Nikon D40 and the Canon 20D is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive perspectives from the front, the top, and the back are available. All size dimensions are rounded to the nearest millimeter.

Size Nikon D40 vs Canon 20D
Compare D40 versus 20D top
Comparison D40 or 20D rear

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Canon 20D is notably larger (31 percent) than the Nikon D40. Moreover, the 20D is substantially heavier (48 percent) than the D40. In this context, it is worth noting that neither the D40 nor the 20D 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. Yet, since both cameras are based around an APS-C sensor, their respective lenses will tend to have similar dimensions and heft. You can compare the optics available for the two cameras in the Nikon Lens Catalog (D40) and the Canon EF Lens Catalog (20D).

Concerning battery life, the D40 gets 470 shots out of its Nikon EN-EL9 battery, while the 20D can take 700 images on a single charge of its Canon BP-511A power pack.

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

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Body Specifications
# image Camera
Model
Camera
Width
Camera
Height
Camera
Depth
Camera
Weight
Battery
Life
Weather
Sealing
Camera
Launch
Launch
Price (USD)
Street
Price
1.
 
Nikon D40 124 mm 94 mm 64 mm 522 g 470 n Nov 2006 499ebay.com
2.
 
Canon 20D 144 mm 106 mm 72 mm 770 g 700 n Aug 2004 1,499ebay.com
3.
 
Canon 40D 146 mm 108 mm 74 mm 822 g 750 n Aug 2007 1,299ebay.com
4.
 
Canon 30D 144 mm 106 mm 74 mm 785 g 750 n Feb 2006 1,399ebay.com
5.
 
Canon XT 127 mm 94 mm 64 mm 540 g 400 n Feb 2005 899ebay.com
6.
 
Canon 10D 150 mm 107 mm 75 mm 850 g 500 n Feb 2003 1,999ebay.com
7.
 
Canon Rebel 142 mm 99 mm 72 mm 649 g 400 n Aug 2003 899ebay.com
8.
 
Nikon D3400 124 mm 98 mm 76 mm 445 g 1200 n Aug 2016 499ebay.com
9.
 
Nikon D3300 124 mm 98 mm 76 mm 430 g 700 n Jan 2014 499ebay.com
10.
 
Nikon D3100 124 mm 96 mm 75 mm 505 g 550 n Aug 2010 599ebay.com
11.
 
Nikon D3000 126 mm 97 mm 64 mm 536 g 500 n Jul 2009 599ebay.com
12.
 
Nikon D60 126 mm 94 mm 64 mm 522 g 500 n Jan 2008 629ebay.com
13.
 
Nikon D40X 124 mm 94 mm 64 mm 522 g 520 n Mar 2007 729ebay.com
14.
 
Nikon D80 132 mm 103 mm 77 mm 668 g 600 n Aug 2006 999ebay.com
15.
 
Nikon D50 133 mm 102 mm 76 mm 620 g 400 n Apr 2005 749ebay.com
16.
 
Nikon D70s 140 mm 111 mm 78 mm 679 g 500 n Apr 2005 899ebay.com
17.
 
Nikon D70 140 mm 111 mm 78 mm 679 g 400 n Jan 2004 999ebay.com
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
padding

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 D40 was launched at a markedly lower price (by 67 percent) than the 20D, 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 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. 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 tend to be associated with larger, more expensive camera bodies and lenses.

Both cameras under consideration feature an APS-C sensor, but their sensors differ slightly in size. The sensor area in the 20D is 9 percent smaller. As a result of these sensor size differences, the cameras have format factors, respectively, of 1.5 (D40) and 1.6. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

Nikon D40 and Canon 20D sensor measures

Despite having a smaller sensor, the 20D offers a higher resolution of 8.2 megapixels, compared with 6 MP of the D40. 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 6.42μm versus 7.85μm for the D40). Moreover, it should be noted that the D40 is much more recent (by 2 years and 2 months) than the 20D, 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 Canon 20D implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the 20D for good quality output (200 dots per inch) amounts to 17.5 x 11.7 inches or 44.5 x 29.7 cm, for very good quality (250 dpi) 14 x 9.3 inches or 35.6 x 23.7 cm, and for excellent quality (300 dpi) 11.7 x 7.8 inches or 29.7 x 19.8 cm. The corresponding values for the Nikon D40 are 15 x 10 inches or 38.2 x 25.4 cm for good quality, 12 x 8 inches or 30.6 x 20.3 cm for very good quality, and 10 x 6.7 inches or 25.5 x 16.9 cm for excellent quality prints.

The Nikon D40 has a native sensitivity range from ISO 200 to ISO 1600, which can be extended to ISO 200-3200. The corresponding ISO settings for the Canon EOS 20D are ISO 100 to ISO 1600, with the possibility to increase the ISO range to 100-3200.

In terms of underlying technology, the D40 is build around a CCD sensor, while the 20D uses a 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.

D40 versus 20D MP

For many cameras, data on sensor performance has been reported by DXO Mark. 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 consideration, the 20D has a markedly higher DXO score than the D40 (overall score 6 points higher), which will translate into better image quality. The advantage is based on 0.9 bits higher color depth, and 0.4 stops in additional low light sensitivity. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.

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Sensor Characteristics
# image Camera
Model
Sensor
Class
Resolution
(MP)
Horiz.
Pixels
Vert.
Pixels
Video
Format
DXO
Portrait
DXO
Landscape
DXO
Sports
DXO
Overall
1.
 
Nikon D40 APS-C 6.0 3008 2000none21.011.056156
2.
 
Canon 20D APS-C 8.2 3504 2336none21.911.072162
3.
 
Canon 40D APS-C 10.1 3888 2592none22.111.370364
4.
 
Canon 30D APS-C 8.2 3504 2336none21.510.873659
5.
 
Canon XT APS-C 8.0 3456 2304none21.810.863760
6.
 
Canon 10D APS-C 6.3 3072 2048none21.110.957157
7.
 
Canon Rebel APS-C 6.3 3072 2048none21.010.854455
8.
 
Nikon D3400 APS-C 24.0 6000 40001080/60p24.813.9119286
9.
 
Nikon D3300 APS-C 24.0 6000 40001080/60p24.312.8138582
10.
 
Nikon D3100 APS-C 14.2 4608 30721080/24p22.511.391967
11.
 
Nikon D3000 APS-C 10.0 3872 2592none22.311.156362
12.
 
Nikon D60 APS-C 10.0 3872 2592none22.511.456265
13.
 
Nikon D40X APS-C 10.0 3872 2592none22.411.451663
14.
 
Nikon D80 APS-C 10.0 3872 2592none22.111.252461
15.
 
Nikon D50 APS-C 6.0 3008 2000none20.910.856055
16.
 
Nikon D70s APS-C 6.0 3008 2000none20.410.352950
17.
 
Nikon D70 APS-C 6.0 3008 2000none20.410.352950
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Neither the D40 nor the 20D offer Live View, so that they cannot project the live image that the sensor receives onto the rear screen. Moreover, both cameras are still-image focused and cannot record videos.
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Feature comparison

Apart from body and sensor, cameras can and do differ across a range of features. The D40 and the 20D 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 viewfinders of both cameras offer the same field of view (95%), but the viewfinder of the 20D has a higher magnification than the one of the D40 (0.56x vs 0.53x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The adjacent table lists some of the other core features of the Nikon D40 and Canon 20D along with similar information for a selection of comparators.

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Core Features
# image 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 D40optical n2.5 / 230 fixed n 1/4000s 2.5/s Y n
2.
 
Canon 20Doptical Y1.8 / 118 fixed n 1/8000s 5.0/s Y n
3.
 
Canon 40Doptical Y3.0 / 230 fixed n 1/8000s 6.5/s Y n
4.
 
Canon 30Doptical Y2.5 / 230 fixed n 1/8000s 5.0/s Y n
5.
 
Canon XToptical n1.8 / 115 fixed n 1/4000s 3.0/s Y n
6.
 
Canon 10Doptical Y1.8 / 118 fixed n 1/4000s 3.0/s Y n
7.
 
Canon Rebeloptical n1.8 / 118 fixed n 1/4000s 2.5/s Y n
8.
 
Nikon D3400optical n3.0 / 921 fixed n 1/4000s 5.0/s Y n
9.
 
Nikon D3300optical n3.0 / 921 fixed n 1/4000s 5.0/s Y n
10.
 
Nikon D3100optical n3.0 / 230 fixed n 1/4000s 3.0/s Y n
11.
 
Nikon D3000optical n3.0 / 230 fixed n 1/4000s 3.0/s Y n
12.
 
Nikon D60optical n2.5 / 230 fixed n 1/4000s 3.0/s Y n
13.
 
Nikon D40Xoptical n2.5 / 230 fixed n 1/4000s 3.0/s Y n
14.
 
Nikon D80optical n2.5 / 230 fixed n 1/4000s 3.0/s Y n
15.
 
Nikon D50optical n2.0 / 130 fixed n 1/4000s 2.5/s Y n
16.
 
Nikon D70soptical n2.0 / 130 fixed n 1/8000s 3.0/s Y n
17.
 
Nikon D70optical n1.8 / 130 fixed n 1/8000s 3.0/s Y n
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.
padding

One feature that is present on the 20D, but is missing on the D40 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 D40 writes its imaging data to SDHC cards, while the 20D uses Compact Flash cards.

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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 D40 and Canon EOS 20D and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

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Input-Output Connections
# image Camera
Model
Hotshoe
Port
Internal
Mic / Speaker
Microphone
Port
Headphone
Port
HDMI
Port
USB
Port
WiFi
Support
NFC
Support
Bluetooth
Support
1.
 
Nikon D40Y- / ----2.0---
2.
 
Canon 20DY- / ----1.1---
3.
 
Canon 40DY- / ----2.0---
4.
 
Canon 30DY- / ----2.0---
5.
 
Canon XTY- / ----2.0---
6.
 
Canon 10DY- / ----1.1---
7.
 
Canon RebelY- / ----1.1---
8.
 
Nikon D3400Ymono / mono--mini2.0--Y
9.
 
Nikon D3300Ymono / monoY-mini2.0---
10.
 
Nikon D3100Ymono / mono--mini2.0---
11.
 
Nikon D3000Y- / ----2.0---
12.
 
Nikon D60Y- / ----2.0---
13.
 
Nikon D40XY- / ----2.0---
14.
 
Nikon D80Y- / ----2.0---
15.
 
Nikon D50Y- / ----2.0---
16.
 
Nikon D70sY- / ----2.0---
17.
 
Nikon D70Y- / ----1.0---
padding

Studio photographers will appreciate that the Canon 20D (unlike the D40) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Both the D40 and the 20D have been discontinued, but can regularly be found used on ebay. The 20D was replaced by the Canon 30D, while the D40 was followed by the Nikon D40X. Further information on the features and operation of the D40 and 20D can be found, respectively, in the Nikon D40 Manual (free pdf) or the online Canon 20D Manual.

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Review summary

So what is the bottom line? Is the Nikon D40 better than the Canon 20D or vice versa? Below is a summary of the relative strengths of each of the two contestants.

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Arguments in favor of the Nikon D40:

  • Larger screen: Has a bigger rear LCD (2.5" vs 1.8") for image review and settings control.
  • More detailed LCD: Has a higher resolution rear screen (230k vs 118k dots).
  • More compact: Is smaller (124x94mm vs 144x106mm) and thus needs less room in the bag.
  • Less heavy: Is lighter (by 248g or 32 percent) and hence easier to carry around.
  • Faster data transfer: Supports a more advanced USB protocol (2.0 vs 1.1).
  • More affordable: Was introduced into a lower priced category (67 percent cheaper at launch).
  • More modern: Reflects 2 years and 2 months of technical progress since the 20D launch.

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Advantages of the Canon EOS 20D:

  • More detail: Has more megapixels (8.2 vs 6MP), which boosts linear resolution by 17%.
  • Better image quality: Scores markedly higher (6 points) in the DXO overall evaluation.
  • Better low-light sensitivity: Can shoot in dim conditions (0.4 stops ISO advantage).
  • Larger viewfinder image: Features a viewfinder with a higher magnification (0.56x vs 0.53x).
  • Easier setting verification: Features a control panel on top to check shooting parameters.
  • Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
  • Faster burst: Shoots at higher frequency (5 vs 2.5 flaps/sec) to capture the decisive moment.
  • Longer lasting: Gets more shots (700 versus 470) out of a single battery charge.
  • Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
  • More heavily discounted: Has been around for much longer (launched in August 2004).

If the number of relative strengths (bullet points above) is taken as a guide, the 20D emerges as the winner of the match-up (10 : 7 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.

D40 07:10 20D

How about other alternatives? Do the specifications of the Nikon D40 and the Canon 20D 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 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 D40 or the 20D 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.

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Expert Camera Reviews
# image  Camera 
 Model 
 AP 
 score 
 CL 
 score 
 DCW 
 score 
 DPR 
 score 
 EPZ 
 score 
 PB 
 score 
Camera
Launch
Launch
Price (USD)
Street
Price
1.
 
Nikon D40..81/100..+ +o4.5/5 Nov 2006 499ebay.com
2.
 
Canon 20D......+ +.... Aug 2004 1,499ebay.com
3.
 
Canon 40D..+ +..+ +4.5/54.5/5 Aug 2007 1,299ebay.com
4.
 
Canon 30D..+ +..+ +o.. Feb 2006 1,399ebay.com
5.
 
Canon XT..80/100..+ +o.. Feb 2005 899ebay.com
6.
 
Canon 10D......+ +.... Feb 2003 1,999ebay.com
7.
 
Canon Rebel......+ +.... Aug 2003 899ebay.com
8.
 
Nikon D34004/5+4/576/1004/54.5/5 Aug 2016 499ebay.com
9.
 
Nikon D33003/5+..77/1004.5/54.5/5 Jan 2014 499ebay.com
10.
 
Nikon D31005/5+ +..72/1004.5/54.5/5 Aug 2010 599ebay.com
11.
 
Nikon D3000..+..72/1004/54.5/5 Jul 2009 599ebay.com
12.
 
Nikon D60..80/100..+ +4/54.5/5 Jan 2008 629ebay.com
13.
 
Nikon D40X..79/100..+ +4/54/5 Mar 2007 729ebay.com
14.
 
Nikon D80..+..+ +o4.5/5 Aug 2006 999ebay.com
15.
 
Nikon D50..78/100..+ +4/54.5/5 Apr 2005 749ebay.com
16.
 
Nikon D70s..........5/5 Apr 2005 899ebay.com
17.
 
Nikon D70......+ +.... Jan 2004 999ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.
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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. Thus, a score needs to be put into the context of the launch date and the launch price 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.

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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.

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    Specifications: Nikon D40 vs Canon 20D

    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 D40 Canon 20D
    Camera Type Digital single lens reflex Digital single lens reflex
    Camera Lens Nikon F mount lenses Canon EF mount lenses
    Launch Date November 2006 August 2004
    Launch Price USD 499 USD 1,499
    Sensor Specs Nikon D40 Canon 20D
    Sensor Technology CCD CMOS
    Sensor Format APS-C Sensor APS-C Sensor
    Sensor Size 23.7 x 15.6 mm 22.5 x 15.0 mm
    Sensor Area 369.72 mm2 337.5 mm2
    Sensor Diagonal 28.4 mm 27 mm
    Crop Factor 1.5x 1.6x
    Sensor Resolution 6 Megapixels 8.2 Megapixels
    Image Resolution 3008 x 2000 pixels 3504 x 2336 pixels
    Pixel Pitch 7.85 μm 6.42 μm
    Pixel Density 1.63 MP/cm2 2.43 MP/cm2
    Moiré control Anti-Alias filter Anti-Alias filter
    Movie Capability no Video no Video
    ISO Setting 200 - 1,600 ISO 100 - 1,600 ISO
    ISO Boost 200 - 3,200 ISO 100 - 3,200 ISO
    DXO Sensor Quality (score) 56 62
    DXO Color Depth (bits) 21.0 21.9
    DXO Dynamic Range (EV) 11.0 11.0
    DXO Low Light (ISO) 561 721
    Screen Specs Nikon D40 Canon 20D
    Viewfinder Type Optical viewfinder Optical viewfinder
    Viewfinder Field of View 95% 95%
    Viewfinder Magnification 0.53x 0.56x
    Top-Level Screen no Top Display Control Panel
    Rear LCD Size 2.5inch 1.8inch
    LCD Resolution 230k dots 118k dots
    LCD Attachment Fixed screen Fixed screen
    Shooting Specs Nikon D40 Canon 20D
    Focus System Phase-detect AF Phase-detect AF
    Continuous Shooting 2.5 shutter flaps/s 5 shutter flaps/s
    Shutter Life Expectancy50 000 actuations50 000 actuations
    Fill Flash Built-in Flash Built-in Flash
    Storage Medium SDHC cards CF cards
    Single or Dual Card Slots Single card slot Single card slot
    Connectivity Specs Nikon D40 Canon 20D
    External Flash Hotshoe Hotshoe
    Studio Flash no PC Sync PC Sync socket
    USB Connector USB 2.0 USB 1.1
    HDMI Port no HDMI no HDMI
    Wifi Support no Wifi no Wifi
    Body Specs Nikon D40 Canon 20D
    Battery Type Nikon EN-EL9 Canon BP-511A
    Battery Life (CIPA)470 shots per charge700 shots per charge
    Body Dimensions 124 x 94 x 64 mm
    (4.9 x 3.7 x 2.5 in)
    144 x 106 x 72 mm
    (5.7 x 4.2 x 2.8 in)
    Camera Weight 522 g (18.4 oz) 770 g (27.2 oz)
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