12 Megapixel Cameras
12MP seems to be the resolution of choice for recent high-end or "serious" DSLR cameras. Again, the actual cross-section at 12MP represents a much wider range of models than you might imagine. The Sony CMOS image sensor, used in the top Sony A700 and the "Pro" Nikon D300, basically set 12MP as the next resolution class. However, the 12MP class also includes the mid-entry level Canon XSi and the 2+ year old full-frame Canon 5D.
Now that the Canon 5D is selling for just a little more than the Nikon D300 and Olympus E-3 you have to consider the 5D in a comparison of prosumer cameras. With the $300 Instant Rebates on the 5D that started in the US today the 5D will probably be even less expensive. It is due for replacement this year but it is still very competitive and some would consider it the best available at its current price point.
The four cameras here represent the 12MP models, including two 1.5X, a 1.6X, and one 1X (full-frame) sensors. All sensors in these four cameras are CMOS, which seems to be the trend for new sensors for reasons discussed in Part 1 of The Digital Sensor.
All images were captured using the manufacturers' 50mm f/1.4 normal lens. This represents an equivalent 35mm focal length of 75mm for the Nikon D300 and Sony A700. The Canon XSi equivalent is 80mm. The full-frame Canon 5D equivalent is the specified 50mm. The distance to the subject was reduced when using the Canon 5D so that the captured image was about the same field of view as the crop-sensor cameras. With the 50mm FOV on the 5D much more of the scene is captured at the same shooting distance than with the crop-sensor cameras.
All images were captured at the same f/4.0 aperture using a tripod in the same location except for the full-frame 5D. Focus was manual and the camera program selected the shutter speed. Lighting was a single 100-watt Tungsten bulb high right, and all cameras were set to the Tungsten preset.
| 12MP Sensor Performance JPEG Comparison over ISO Range |
||||
| ISO | Canon XSi | Nikon D300 | Sony A700 | Canon 5D (Full-Frame) |
| 100 |  |
 |
 |
 |
| 200 |  |
 |
 |
 |
| 400 |  |
 |
 |
 |
| 800 |  |
 |
 |
 |
| 1600 |  |
 |
 |
 |
| 3200 |  |
 |
 |
|
| 6400 |  |
 |
||
Click on any of the above image crops for the full image. Note: Full size images are between 3.9MB and 11.4MB! |
||||
12 Megapixel sensors seem to be the hot competition arena in current DSLRs, and it certainly shows in the very different approaches to in-camera processing shown in the JPEGS from these four cameras. You should take a close look at the Sony A700 and Nikon D300 results since they are based on the same sensor. The impact of in-camera processing on the finished JPEG can’t be illustrated more clearly than by comparing the Sony and Nikon images.
You should also pixel peep the images from the full-frame Canon 5D and compare them to the Nikon and Sony. You will probably find a smaller difference in image quality than you expected, which just demonstrates how much progress has been made in sensor technology since the Canon 5D was introduced more than two years ago. The successor to the 5D is expected later this year and it is rumored to feature a 16 megapixel full-frame sensor.
Facebook
Twitter
RSS
22 Comments
View All Comments
Wesley Fink - Tuesday, May 20, 2008 - link
The goal was to produce a fair comparison and as staed in the article we do have the TIFF files available. The purpose was never to show there is minimal difference in RAW and JPEG. As we were preparing to post there were concerns that the TIFFs, at 45mb each, might cripple our server as a direct image view "click to see". That is the ONLY reason we converted to Maximum JPEG format directly from the RAW file.Since there is some interest we will likely produce a ZIP of the TIFFS and create a download link on the RAW examples page.
Wesley Fink - Tuesday, May 20, 2008 - link
Another option would be to post a ZIP of the RAW files. The latest Adobe Camera RAW can handle the PEF format in either Photoshop CS3 or Elements 5 and 6. OR we could save in Adobe DNG format and the DNG files could be read in almost any recent Photoshop or Elements - but not other programs. If either of these is a preferred option please let us know in these comments and we will go with what readers want.pinto4402 - Tuesday, May 20, 2008 - link
A ZIP file of images in RAW or DNG format would be great. I don't think any other review site is doing this. Although I won't download them each time I read an article, I would absolutely look at them VERY carefully if I'm interested in a camera.pinto4402 - Tuesday, May 20, 2008 - link
For your sample images, have you thought about using a high quality mannequin head (sounds creepy, I know), or silk flowers? Although not perfect, this would be much preferable to the product boxes you’ve been using. This will allow you to precisely control your test protocol while at the same time obtaining useful information about the imaging capabilities of cameras being tested).Overall, your camera reviews are better than average and if you’re serious about it, why not make your testing as good as possible?
haplo602 - Tuesday, May 20, 2008 - link
"Serious photo hobbyists will also be facing difficult decisions today and even more so in the near future. The cost of larger and larger sensors has been dropping rapidly; and CMOS sensor development from all the sensor manufacturers is also a factor in lowering costs and increasing resolution. Like it or not Canon and Nikon have already begun segregating their SLR line into full-frame and APS-C sensors. Those who wondered why Sony was introducing mainly full-frame lenses will finally get their answer later this year with Sony's 24.6MP full-frame flagship model."This exactly makes me a happy film shooter :-) There's one disdvantage to full frame sensors however. They increase demand for full frame lenses and increase the prices for me :-(
Anyway good article. I'd have one comment and one request.
Comment: There was lots of heated discussion about your sample images (there is one again so far). Would be good if you could shoot manual with f/4.0 and whatever shutter reading for the selected ISO but same for all cameras to make the captured EV consistent. This should in theory lead to all images having same brightness. Of course that will vary by camera processing, but at least you get one more point you can compare from the same series of shots.
Request: Can you make an article on the processing path of different camera makes and sensors ? You covered the digital conversion so far, but the A/D part would be nice to have too. F.e how ISO is controlled (analog gain or digital interpolation) etc. Also explanation what a higher bit-depth sensor means (12 vs 16 bit sensor and A/D). I know these things are pretty basic, but this will create some common group which you can reference in the future and avoid stupid questions (well some of them at least).
7thSerapHim - Tuesday, May 20, 2008 - link
Does anyone agree that a better object with clearly defined lines and colors should be used instead, for the comparison crops?Most of the time these mass-produced product boxes have mediocre color matching and well-defined lines so it shouldn't be used as a 100% comparison crop.
The shots also seem to have a substantial amount of chromatic aberration, or maybe just due to pixel peeping, hmmm...
sprockkets - Tuesday, May 20, 2008 - link
JPEG compression control would be nice on the p&s. The Canon SD1000 has compression artifacts all over, thus making the pictures it takes look worse than a $90 Nikon.dblevitan - Tuesday, May 20, 2008 - link
There are two key advantages of RAW that you missed and that could be useful to even people who are slighly interested in improving images.First, RAW provides 12 or 14 bits/pixel while JPEG only provides 8 bits. This is extremely relevant if you edit at all in Photoshop/Lightroom because any kind of level adjustment (even auto) will cause more color degradation with an 8 bit image than with a 16 bit image (which is what the 12 bit RAW files are generally processed into).
Second, RAW provides a better chance of recovering improperly exposed images by allowing at least 1/2 stop of exposure correction without any penalty and often more without significant issues. With JPEG you simply won't get this.
Wesley Fink - Tuesday, May 20, 2008 - link
You are absolutely correct that while JPEG is 24 bits per pixel it is only 8 bits per color channel (red, green, blue). The Pentax K20D is specified as a 14-bit A/D processor.Photoshop and other processing software, as you point out, normally processes this in 16-bit. However, it really doesn't matter in the end how the program processed it or saved it, what matters is the input bit depth. Many are not aware of this, but Photoshop also processes JPEGS as 16-bit on more powerful computers, but this just speeds up processing because you start with 8-bit and save as 8-bit with JPEG. There is no real advantage processing 12-bit files as 16-bit except processing speed as you don't gain real resolution improvements.
I agree RAW SHOULD allow more dynamic range, but some of the newest models like the Nikon D300 can actually do just as well or better in dynamic range in JPEG. However, in general what you say is true although it is changing as the processing power in DSLRs is improving.
What we really need is a higher bit-width JPEG standard. Let's hope the JPEG standards committee is hard at work on just that.
Bull Dog - Monday, May 19, 2008 - link
Is it just me or is the third page missing?