First Look: Canon 5D Mark II
by Wesley Fink on December 4, 2008 3:00 AM EST- Posted in
- Digital Camera
Full-Frames and APS-C Compared
The Canon 5D Mark II is the update to the camera that created the $3000 full-frame DSLR market - namely the Canon 5D in 2005. Canon had this market all to their self for the first two years, but during the past year Nikon and Sony have both introduced several models to compete in the full-frame DSLR market.
The 5D2 sensor is approximately the size of a frame of 35mm film, which is 24x36mm, and resolution is 21.1MP - a significant increase from the original 5D at 12.8MP. The new Canon 5D2 compares very well to the reolution of the recently introduced Sony A900, which at 24.6MP is the highest resolution currently available in a full-frame camera. Compare this to most other DSLR cameras today, where the sensor size is closer to APS-C size. The smaller APS-C sensor used in most other cameras results in the lenses appearing to be 150% to 200% longer than the marked focal length. On the Canon 5D Mark II and other full-frame DSLR cameras lenses behave exactly as they would on 35mm, with no crop factor.
In the computer world, smaller and smaller traces mean higher density, more transistors, and generally better and faster performance. However, the digital sensor is not a digital device; instead, it's an analog device that gathers light and converts it into a digital signal. Thus the reverse is true in sensors in that larger sensor size is almost always better, with everything else equal. As you can see in the chart below, the APS-C sensors aren't even half of the area of a full-frame sensor. With a range of 28.1% to 42.4% of full-frame size, there is clearly a lot more information that can be potentially captured with a full-frame sensor.
| DSLR Sensor Comparison | ||||
| Camera | Effective Sensor Resolution | Sensor Dimensions and Area | % of Full-Frame | Sensor Density (MP/cm2) |
| Olympus E-520/E-3 | 10 | 13.5x18 2.43 cm2 | 28.10% | 4 |
| Canon Xsi | 12.2 | 14.8x22.2 3.28 cm2 | 38.00% | 3.7 |
| Sony A350 | 14.2 | 15.8x23.6 3.72 cm2 | 42.90% | 3.8 |
| Pentax K20D | 14.6 | 15.6x23.4 3.65 cm2 | 42.20% | 4 |
| Canon 50D | 15.1 | 14.9x22.3 3.32 cm2 | 38.40% | 4.5 |
| Sony A700, Nikon D300, Nikon D90 | 12.3 | 15x23.5 3.66 cm2 | 42.40% | 3.3 |
| Nikon D700/Nikon D3 | 12.1 | 24x36 8.64 cm2 | 100% | 1.4 |
| Canon 5D | 12.8 | 24x36 8.64 cm2 | 100% | 1.5 |
| Canon 5D Mark II | 21.1 | 24x36 8.64 cm2 | 100% | 2.4 |
| Canon 1Ds Mark III | 21.1 | 24x36 8.64 cm2 | 100% | 2.4 |
| Sony A900/Nikon D3x | 24.6 | 24x35.9 8.61 cm2 | 100% | 2.9 |
The last column in the chart is the one that tells the story most accurately, however. Here the resolution of the sensor is divided by the sensor area to yield a sensor density. The lower the density, the larger the individual pixel size, and the more information that pixel can gather - all else being equal. There are a few surprises here, such as the Sony A350 being essentially the same density as the Canon XSi, and the new Canon 50D having the highest density of any current DSLR camera.
The last column does put into perspective the true potential of the full-frame sensor and sheds some light on the true meaning of Canon's 21.1MP sensor and Sony/Nikon's 24.6MP A900/D3x sensor. At 2.4MP per cm2 the 5D2 still exhibits a lower density and theoretically better high ISO performance than any current APS-C DSLR. This is very much at odds with the ridiculous claims many on the web are making about full-frame cameras going too high in resolution. In fact, sensor density on the 5D2 is significantly lower than the 10MP Canon 40D, which has a density of 3.1.
The point is that any issues the 5D2 may have with noise are not the result of pixels being "too small". All else being equal the high ISO noise should be at least as good as an 8 to 10MP Canon sensor. Where the new Canon does suffer is in comparison to sensor density of other full-frame sensors. In that metric the Canon 5D2 has about 65% more pixels per cm2 than the Nikon D3/D700 and Canon 5D, and keeping up in high ISO performance with those cameras would be quite a feat. The Canon 5D Mark II is, however, slightly lower in resolution than the Sony A900 and Nikon D3X that feature 24.6MP sensors, although the difference between 21.1 and 24.5/24.6 has to be considered negligible.
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n4bby - Friday, December 5, 2008 - link
> I used to trust DPR but they are biased against Canon which I don't like.huh? i don't think so at all... i think they are pretty fair. they have always rated Canon products favorably when deserved, but remain critical enough to give relatively impartial opinions. if they say Nikon does some things better, it's because they do - Canon is not perfect, and there are a few things Nikons have always done better. (and no, i am not a Nikon user - i have only Canon gear.)
n4bby - Thursday, December 4, 2008 - link
wesley,> It is not the wide ISO wonder of the 5D2 or the D700, but it is definitely the highest resolution image at lower ISO ratings.
i'm not sure how you came to this conclusion. looking at the ISO100 images, the 5d2 seems to resolve every bit as well the Sony, and with the much lower noise levels i can actually make out a little more detail. in any case, you would need a resolution chart to really determine - did you shoot one?
> The 5D2 is close in resolution, however - much closer than the D700/D3.
with half the pixels i wouldn't expect the Nikons to be close.....
pinto4402 - Thursday, December 4, 2008 - link
Wow. I'm in love. After three years, Canon finally produces a camera which is worthy of replacing my beloved 5D. I fear, however, that the images produced by this camera will kill my hard drives for sure. I only photograph in RAW mode, saving the images in TIFF.Wesley, I enjoy reading your reviews, but for the love of God, please use something else other than that Nvidia box for your test images. It's time to make a clean break, consistency be damned! The thing with noise I worry about it how it affects key facial features (eyes and lips). Your test setup is not as helpful as could be. A feasible alternative is a good quality mannequin head. I hope you will consider it.
Also, are you going to be doing any comparisons of the leading noise reduction programs?
Wesley Fink - Thursday, December 4, 2008 - link
I will be replacing my test setup with something more useful. However in the interest of bringing you the first real comparison published in just one day after buyers began receiving production 5D2s, I used the setup I already had used for all the compare shots.I hope readers will forgive me. Reshooting everything with a new setup would have added several days to the review time and I suspected you wanted this comparison fast.
melgross - Thursday, December 4, 2008 - link
I would like to see the same reduced sized samples when compared to the D3/700 with both the Canon and Sony. I'm also of the opinion that it is more useful in showing a real comparison, print size to print size.Also, why were the images of the Canon so much denser? That will also affect the way the noise looks.
Wesley Fink - Thursday, December 4, 2008 - link
Our A900 review "Sony A900: A Closer Look at 24.6MP Resolution and Noise" contains image area adjusted A900 images that match the 12 megapixels of the D700 and the 5D. You will find the review by clicking on the Digital Cameras tab above.melgross - Friday, December 5, 2008 - link
Yes, I read that review when it came out.I mean the new 5D mkII compared to the a900, and the Nikon, with all three (or four, if including the 1Ds mkII) shown at the same size.
What about the exposure?
Lord 666 - Thursday, December 4, 2008 - link
Agreed that this review was a much improved effort and found it informative as well.tonyeck - Thursday, December 4, 2008 - link
I am very happy with my 5D mkII apart from one thing - a stuck pixel! It's fine for photographs, and it's almost expected with 21 megapixels... However, with video, stuck pixels show up like crazy!Have a look at this still from a video I took:
http://flickr.com/photos/tonysphotographs/30810827...">http://flickr.com/photos/tonysphotographs/30810827...
Milleman - Friday, December 5, 2008 - link
Yea...That dead pixel looks not good at all. Can't you have the sensor replaced by warranty? I mean, this is not a El Cheapo camera you just bought! Canon should have a replacement policy for dead pixels. I'm glad you bringning this up, as I'm about to buy a 5D2 myself. I will certainly try the video and look for dead pixels.
Could be a good point if Anand, Wesley Fink, looks att dead pixels and the manufacturers policy with this issue. The more pixels, the bigger the chance. It's the same problem as the LCD screen buyers have. Would be an interresting article indeed.