Canon 30D vs Sony A7S
The Canon EOS 30D and the Sony Alpha A7S are two digital cameras that were revealed to the public, respectively, in February 2006 and April 2014. The 30D is a DSLR, while the A7S is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (30D) and a full frame (A7S) sensor. The Canon has a resolution of 8.2 megapixels, whereas the Sony provides 12 MP.
Below is an overview of the main specs of the two cameras as a starting point for the comparison.
Going beyond this snapshot of core features and characteristics, what are the differences between the Canon EOS 30D and the Sony Alpha A7S? 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.
The physical size and weight of the Canon 30D and the Sony A7S 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 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 Sony A7S is notably smaller (22 percent) than the Canon 30D. Moreover, the A7S is substantially lighter (38 percent) than the 30D. It is noteworthy in this context that the A7S is splash and dust-proof, while the 30D 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. 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 Canon EF Lens Catalog (30D) and the Sony FE Lens Catalog (A7S). Mirrorless cameras, such as the A7S, 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 30D gets 750 shots out of its BP-511A battery, while the A7S can take 380 images on a single charge of its NP-FW50 power pack. The power pack in the A7S can be charged via the USB port, which can be very convenient when travelling.
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.
|1.||Canon 30D||144 mm||106 mm||74 mm||785 g||750||n||Feb 2006||1,399||ebay.com|
|2.||Sony A7S||127 mm||94 mm||48 mm||489 g||380||Y||Apr 2014||2,499||ebay.com|
|3.||Canon 70D||139 mm||104 mm||79 mm||755 g||920||Y||Jul 2013||1,199||ebay.com|
|4.||Canon 60D||145 mm||106 mm||79 mm||755 g||1100||Y||Aug 2010||1,399||ebay.com|
|5.||Canon 7D||148 mm||111 mm||74 mm||860 g||800||Y||Sep 2009||1,699||ebay.com|
|6.||Canon 50D||146 mm||108 mm||74 mm||822 g||800||Y||Aug 2008||1,299||ebay.com|
|7.||Canon 40D||146 mm||108 mm||74 mm||822 g||750||n||Aug 2007||1,299||ebay.com|
|8.||Canon 400D||127 mm||84 mm||65 mm||556 g||370||n||Aug 2006||799||ebay.com|
|9.||Canon 350D||127 mm||94 mm||64 mm||540 g||400||n||Feb 2005||899||ebay.com|
|10.||Canon 20D||144 mm||106 mm||72 mm||770 g||700||n||Aug 2004||1,499||ebay.com|
|11.||Nikon D750||141 mm||113 mm||78 mm||750 g||1230||Y||Sep 2014||2,299||ebay.com|
|12.||Nikon D80||132 mm||103 mm||77 mm||668 g||600||n||Aug 2006||999||ebay.com|
|13.||Nikon D200||147 mm||113 mm||74 mm||920 g||400||Y||Nov 2005||1,699||ebay.com|
|14.||Sony A7S II||127 mm||96 mm||60 mm||627 g||370||Y||Sep 2015||2,999||ebay.com|
|15.||Sony A7||127 mm||94 mm||48 mm||474 g||340||Y||Oct 2013||1,699||ebay.com|
|16.||Sony A7R||127 mm||94 mm||48 mm||465 g||340||Y||Oct 2013||2,299||ebay.com|
|17.||Sony RX1R||113 mm||65 mm||70 mm||482 g||270||n||Jun 2013||2,799||ebay.com|
|Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
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 30D was launched at a markedly lower price (by 44 percent) than the A7S, 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.
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 Canon 30D features an APS-C sensor and the Sony A7S a full frame sensor. The sensor area in the A7S is 153 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.6 and 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.
With 12MP, the A7S offers a higher resolution than the 30D (8.2MP), but the A7S nevertheless has larger individual pixels (pixel pitch of 8.45μm versus 6.42μm for the 30D) due to its larger sensor. Moreover, the A7S is a much more recent model (by 8 years and 1 month) than the 30D, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixel-units.
The resolution advantage of the Sony A7S implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A7S for good quality output (200 dots per inch) amounts to 21.2 x 14.2 inches or 53.8 x 36 cm, for very good quality (250 dpi) 17 x 11.3 inches or 43.1 x 28.8 cm, and for excellent quality (300 dpi) 14.1 x 9.4 inches or 35.9 x 24 cm. The corresponding values for the Canon 30D are 17.5 x 11.7 inches or 44.5 x 29.7 cm for good quality, 14 x 9.3 inches or 35.6 x 23.7 cm for very good quality, and 11.7 x 7.8 inches or 29.7 x 19.8 cm for excellent quality prints.
The Canon EOS 30D has a native sensitivity range from ISO 100 to ISO 1600, which can be extended to ISO 100-3200. The corresponding ISO settings for the Sony Alpha A7S are ISO 100 to ISO 102400, with the possibility to increase the ISO range to 50-409600.
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 consideration, the A7S offers substantially better image quality than the 30D (overall score 28 points higher). The advantage is based on 2.4 bits higher color depth, 2.4 EV in additional dynamic range, and 2.3 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.
|2.||Sony A7S||Full Frame||12.0||4240||2832||1080/60p||23.9||13.2||3702||87|
|11.||Nikon D750||Full Frame||24.2||6016||4016||1080/60p||24.8||14.5||2956||93|
|14.||Sony A7S II||Full Frame||12.0||4240||2832||4K/30p||23.6||13.3||2993||85|
|15.||Sony A7||Full Frame||24.0||6000||4000||1080/60p||24.8||14.2||2248||90|
|16.||Sony A7R||Full Frame||36.2||7360||4912||1080/60p||25.6||14.1||2746||95|
|17.||Sony RX1R||Full Frame||24.0||6000||4000||1080/60p||25.0||13.6||2537||91|
Many modern cameras are not only capable of taking still images, but can also record movies. The A7S indeed provides for movie recording, while the 30D does not. The highest resolution format that the A7S can use is 1080/60p.
Apart from body and sensor, cameras can and do differ across a range of features. For example, the A7S has an electronic viewfinder (2400k dots), while the 30D 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 A7S offers a wider field of view (100%) than the one in the 30D (95%), so that a larger proportion of the captured image is visible in the finder. In addition, the viewfinder of the A7S has a higher magnification (0.71x vs 0.56x), 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 Canon 30D and Sony A7S in connection with corresponding information for a sample of similar cameras.
|1.||Canon 30D||optical||Y||2.5 / 230||fixed||n||1/8000s||5.0/s||Y||n|
|2.||Sony A7S||2400||n||3.0 / 921||tilting||n||1/8000s||5.0/s||n||n|
|3.||Canon 70D||optical||Y||3.0 / 1040||swivel||Y||1/8000s||7.0/s||Y||n|
|4.||Canon 60D||optical||Y||3.0 / 1040||swivel||n||1/8000s||5.3/s||Y||n|
|5.||Canon 7D||optical||Y||3.0 / 920||fixed||n||1/8000s||8.0/s||Y||n|
|6.||Canon 50D||optical||Y||3.0 / 920||fixed||n||1/8000s||6.3/s||Y||n|
|7.||Canon 40D||optical||Y||3.0 / 230||fixed||n||1/8000s||6.5/s||Y||n|
|8.||Canon 400D||optical||n||2.5 / 230||fixed||n||1/4000s||3.0/s||Y||n|
|9.||Canon 350D||optical||n||1.8 / 115||fixed||n||1/4000s||3.0/s||Y||n|
|10.||Canon 20D||optical||Y||1.8 / 118||fixed||n||1/8000s||5.0/s||Y||n|
|11.||Nikon D750||optical||Y||3.2 / 1229||tilting||n||1/4000s||6.0/s||Y||n|
|12.||Nikon D80||optical||n||2.5 / 230||fixed||n||1/4000s||3.0/s||Y||n|
|13.||Nikon D200||optical||Y||2.5 / 230||fixed||n||1/8000s||5.0/s||Y||n|
|14.||Sony A7S II||2400||n||3.0 / 1229||tilting||n||1/8000s||5.0/s||n||Y|
|15.||Sony A7||2400||n||3.0 / 1230||tilting||n||1/8000s||5.0/s||n||n|
|16.||Sony A7R||2400||n||3.0 / 1230||tilting||n||1/8000s||4.0/s||n||n|
|17.||Sony RX1R||optional||n||3.0 / 1229||fixed||n||1/4000s||5.0/s||Y||n|
|Notes: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.|
One difference between the cameras concerns the presence of an on-board flash. The 30D has one, while the A7S does not. While the built-in flash of the 30D is not very powerful, it can at times be useful as a fill-in light.
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, the A7S is one of those camera that have an additional 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 30D writes its imaging data to Compact Flash cards, while the A7S uses SDXC or Memory Stick PRO Duo cards.
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 Canon EOS 30D and Sony Alpha A7S and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
Mic / Speaker
|1.||Canon 30D||Y||- / -||-||-||-||2.0||-||-||-|
|2.||Sony A7S||Y||stereo / mono||Y||Y||micro||2.0||Y||Y||-|
|3.||Canon 70D||Y||stereo / mono||Y||-||mini||2.0||Y||-||-|
|4.||Canon 60D||Y||mono / mono||Y||-||mini||2.0||-||-||-|
|5.||Canon 7D||Y||mono / -||Y||-||mini||2.0||-||-||-|
|6.||Canon 50D||Y||- / -||-||-||mini||2.0||-||-||-|
|7.||Canon 40D||Y||- / -||-||-||-||2.0||-||-||-|
|8.||Canon 400D||Y||- / -||-||-||-||2.0||-||-||-|
|9.||Canon 350D||Y||- / -||-||-||-||2.0||-||-||-|
|10.||Canon 20D||Y||- / -||-||-||-||1.1||-||-||-|
|11.||Nikon D750||Y||stereo / mono||Y||Y||mini||2.0||Y||-||-|
|12.||Nikon D80||Y||- / -||-||-||-||2.0||-||-||-|
|13.||Nikon D200||Y||- / -||-||-||-||2.0||-||-||-|
|14.||Sony A7S II||Y||stereo / mono||Y||Y||micro||2.0||Y||Y||-|
|15.||Sony A7||Y||stereo / mono||Y||Y||micro||2.0||Y||Y||-|
|16.||Sony A7R||Y||stereo / mono||Y||Y||micro||2.0||Y||Y||-|
|17.||Sony RX1R||Y||stereo / mono||Y||-||mini||2.0||-||-||-|
It is notable that the A7S offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the 30D does not provide wifi capability.
Studio photographers will appreciate that the Canon 30D (unlike the A7S) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
Both the 30D and the A7S have been discontinued, but can regularly be found used on ebay. The 30D was replaced by the Canon 40D, while the A7S was followed by the Sony A7S II. Further information on the features and operation of the 30D and A7S can be found, respectively, in the Canon 30D Manual (free pdf) or the online Sony A7S Manual.
So what conclusions can be drawn? Which of the two cameras – the Canon 30D or the Sony A7S – 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 Canon EOS 30D:
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Easier setting verification: Features an LCD display on top to control shooting parameters.
- Longer lasting: Can take more shots (750 versus 380) on a single battery charge.
- Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- More affordable: Was introduced into a lower priced category (44 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in February 2006).
Reasons to prefer the Sony Alpha A7S:
- More detail: Has more megapixels (12 vs 8.2MP), which boosts linear resolution by 21%.
- Better image quality: Scores substantially higher (28 points) in the DXO overall evaluation.
- Richer colors: Generates noticeably more natural colors (2.4 bits more color depth).
- More dynamic range: Captures a broader range of light and dark details (2.4 EV of extra DR).
- Better low-light sensitivity: Can shoot in dim conditions (2.3 stops ISO advantage).
- Broader imaging potential: Can capture not only stills but also 1080/60p video.
- 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 (0.71x vs 0.56x).
- Larger screen: Has a bigger rear LCD (3.0" vs 2.5") for image review and settings control.
- More detailed LCD: Has a higher resolution rear screen (921k vs 230k dots).
- More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (127x94mm vs 144x106mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 296g or 38 percent) and is thus easier to take along.
- Easier travel charging: Can be conveniently charged via its USB port.
- Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
- More legacy lens friendly: Can use many non-native lenses via adapters.
- Easier file upload: Has wifi built in for automatic backup or image transfer to the web.
- Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
- More modern: Reflects 8 years and 1 month of technical progress since the 30D launch.
If the number of relative strengths (bullet points above) is taken as a guide, the A7S is the clear winner of the contest (21 : 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 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 Canon 30D and the Sony A7S 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 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 30D and the A7S 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.
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.
|1.||Canon 30D||..||+ +||..||+ +||o||..||Feb 2006||1,399||ebay.com|
|2.||Sony A7S||4/5||..||..||86/100||4.5/5||5/5||Apr 2014||2,499||ebay.com|
|3.||Canon 70D||5/5||+ +||..||83/100||4.5/5||5/5||Jul 2013||1,199||ebay.com|
|4.||Canon 60D||5/5||+||..||79/100||4/5||4.5/5||Aug 2010||1,399||ebay.com|
|5.||Canon 7D||5/5||+ +||..||84/100||4.5/5||4.5/5||Sep 2009||1,699||ebay.com|
|6.||Canon 50D||..||+ +||..||+ +||4.5/5||4.5/5||Aug 2008||1,299||ebay.com|
|7.||Canon 40D||..||+ +||..||+ +||4.5/5||4.5/5||Aug 2007||1,299||ebay.com|
|8.||Canon 400D||..||+ +||..||+ +||o||4/5||Aug 2006||799||ebay.com|
|9.||Canon 350D||..||80/100||..||+ +||o||..||Feb 2005||899||ebay.com|
|10.||Canon 20D||..||..||..||+ +||..||..||Aug 2004||1,499||ebay.com|
|11.||Nikon D750||5/5||+ +||4/5||90/100||4.5/5||4.5/5||Sep 2014||2,299||ebay.com|
|12.||Nikon D80||..||+||..||+ +||o||4.5/5||Aug 2006||999||ebay.com|
|13.||Nikon D200||..||+ +||..||+ +||o||..||Nov 2005||1,699||ebay.com|
|14.||Sony A7S II||5/5||+||..||..||4.5/5||5/5||Sep 2015||2,999||ebay.com|
|15.||Sony A7||5/5||+ +||..||80/100||5/5||5/5||Oct 2013||1,699||ebay.com|
|16.||Sony A7R||5/5||+ +||..||82/100||4.5/5||5/5||Oct 2013||2,299||ebay.com|
|17.||Sony RX1R||5/5||..||..||..||4/5||4.5/5||Jun 2013||2,799||ebay.com|
|Notes: (+ +) 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.
Other camera comparisons
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Specifications: Canon 30D vs Sony A7S
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 Model||Canon 30D||Sony A7S|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Canon EF mount lenses||Sony E mount lenses|
|Launch Date||February 2006||April 2014|
|Launch Price||USD 1,399||USD 2,499|
|Sensor Specs||Canon 30D||Sony A7S|
|Sensor Format||APS-C Sensor||Full Frame Sensor|
|Sensor Size||22.5 x 15.0 mm||35.8 x 23.9 mm|
|Sensor Area||337.5 mm2||855.62 mm2|
|Sensor Diagonal||27 mm||43 mm|
|Sensor Resolution||8.2 Megapixels||12 Megapixels|
|Image Resolution||3504 x 2336 pixels||4240 x 2832 pixels|
|Pixel Pitch||6.42 μm||8.45 μm|
|Pixel Density||2.43 MP/cm2||1.40 MP/cm2|
|Moiré control||Anti-Alias filter||Anti-Alias filter|
|Movie Capability||no Video||1080/60p Video|
|ISO Setting||100 - 1,600 ISO||100 - 102,400 ISO|
|ISO Boost||100 - 3,200 ISO||50 - 409,600 ISO|
|Image Processor||DIGIC 2||BIONZ X|
|DXO Sensor Quality (score)||59||87|
|DXO Color Depth (bits)||21.5||23.9|
|DXO Dynamic Range (EV)||10.8||13.2|
|DXO Low Light (ISO)||736||3702|
|Screen Specs||Canon 30D||Sony A7S|
|Viewfinder Type||Optical viewfinder||Electronic viewfinder|
|Viewfinder Field of View||95%||100%|
|Viewfinder Resolution||2400k dots|
|Top-Level Screen||Control Panel||no Top Display|
|LCD Framing||Live View|
|Rear LCD Size||2.5inch||3.0inch|
|LCD Resolution||230k dots||921k dots|
|LCD Attachment||Fixed screen||Tilting screen|
|Shooting Specs||Canon 30D||Sony A7S|
|Focus System||Phase-detect AF||Contrast-detect AF|
|Manual Focusing Aid||no Peaking Feature||Focus Peaking|
|Max Shutter Speed (mechanical)||1/8000s||1/8000s|
|Continuous Shooting||5 shutter flaps/s||5 shutter flaps/s|
|Electronic Shutter||no E-Shutter||YES|
|Fill Flash||Built-in Flash||no On-Board Flash|
|Storage Medium||CF cards||MS or SDXC cards|
|Single or Dual Card Slots||Single card slot||Single card slot|
|Connectivity Specs||Canon 30D||Sony A7S|
|Studio Flash||PC Sync socket||no PC Sync|
|USB Connector||USB 2.0||USB 2.0|
|HDMI Port||no HDMI||micro HDMI|
|Microphone Port||no MIC socket||External MIC port|
|Headphone Socket||no Headphone port||Headphone port|
|Wifi Support||no Wifi||Wifi built-in|
|Near-Field Communication||no NFC||NFC built-in|
|Body Specs||Canon 30D||Sony A7S|
|Environmental Sealing||not weather sealed||Weathersealed body|
|Battery Life (CIPA)||750 shots per charge||380 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
144 x 106 x 74 mm
(5.7 x 4.2 x 2.9 in)
127 x 94 x 48 mm
(5.0 x 3.7 x 1.9 in)
|Camera Weight||785 g (27.7 oz)||489 g (17.2 oz)|
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