Canon EOS 40D review

The Canon 40D is the real successor of the popular 20D (I don't consider the 30D - it was just a very minor update). The new Canon offers some major improvement over the 20/30D, and in some aspects it is even better than professional 1 series (more advanced Live View, lighter and smaller body). Even though the image quality has not much improved, it was already pretty good, and the new cameras offers many new features, that make it my choice as DSLR body.

Camera Specifications

Image quality

The first thing that you will notice in the specs of 40D is the increased resolution, from the 8 megapixels of the 20D to 10 megapixel. There is not an huge difference between 8 and 10 megapixels, but the resolution improvement is welcome - it allows to capture a bit more detail, to make larger prints or larger crops. By the way, the 40D has also a slightly smaller sensor (22.2x14.8mm vs the 22.5x15mm of the 20D), that gives a little higher field of fiew multiplier - 1.62x vs 1.60x of the 20D. I have compared the 40D with the 20D using my sharpest lens, and of course tripod and MLU (for 20D) or Live View Mode 1 (for 40D). The RAW photos had been converted with the same settings in ACR.

The entire test target, resized to 720 pixels.

100% crop from the photo taken with the Canon 20D

100% crop from the photo taken with the Canon 40D. The camera clearly captures more fine detail.

What about noise? You might be surprised to discover that 40D is about 0.5-0.7 stops noisier than the 20D - an unexpected step back, but it is the price to pay for more megapixels in the same sensor size. That said, I doubt that the Nikon D300, the Sony A700 or the Olympus E-3 offer a better image quality; the small APS-C sensor can not compete with larger sensors in terms of noise, in particular with high resolution and small pixel, as in these cameras.

The 100% crop from the 20D at 1600 ISO. The noise is relatively low, considering that it is a three years old camera!

The crop the 40D (resized at 8mp), with the exposure suggested my the camera. The noise is similar to 20D noise - I'd say just a little more, in this crop the 40D seem about 0.2 stop worse than 20D. But the shutter speed is 1/2 stop longer!

Indeed, the 40D sensor is about 0.5 stops less sensitive than 20D sensor - in other words, if you take a photo with the same exposure, the image taken with the 40D will be 0.5 stops darker. Overall, I'd say that in terms of ISO/noise performance the 40D is nearly 0.7 stop worse than the 20D.

Live View and Silent Shooting

As all new Canon cameras, the 40D has Live View. You can use the big LCD screen to frame the photo; you can judge in real-time the exposure (it is possible to simulate the exposure and to view the histogram in real time!) and the depth of field, and you can even magnify up to 10x a portion of the image for a more accurate focussing. Live View is mainly for macro, landscapes and other still subjects, beucause the AF functionality is limited - by default, AF is disabled when you use live view; you can still AF with the AF-On button (when you press AF-on, the camera quickly stops live view, it focusses, and when you release the button it comes back to live view). Another nice feature of live view is to show a super-imposed grid, that helps to compose the photo and to avoid tilted horizons.

I often use the Sigma 180 Macro with 2.0 TC, that gives a very dark 360mm f/7.1. The AF of course does not work, so you are forced to use MF: it is far from easy and, unless you have a very good eye, you will get many out of focus photos (with the 20D or other cameras without live view). Live View is another world! You frame the photo through a big, bright, sharp LCD screen, then you zoom at 10x and you fine tune the focus on the subject. You can even stop down the lens to the effective aperture (with the DOF preview button) to check the depth of fied, both on the entire image or in a 10x magnified area...it is fantastic to see in real time the effect of different apertures! And remember that while the viewfinder becomes extremely dark if you press the DOF preview button, the LCD always maintain the same brightness...I love it!

Last but not least, with live view you no longer need the Angle-Finder. In the past I used a lot the Canon Angle-Finder C for macro photography, it is very useful when you have to frame a subject from weird angles, but I don't like it a lot: the built quality is average, it makes more difficult to find the subject, it makes the viewfinder even darker, and it has a crappy diopter adjustment system (you have to change the diopter every time that you switch from 1.25x to 2.5x). The live view is so much better! This is really one of my preferred features of the 40D.

The Live View of the 40D has some big improvements in comparison with the live view of the 1D3. The 40D offers a Live View option called "Silent Shooting", that offers many advantages. To understand Silent Shooting, you have to know how the Live View works in 1D3 and 40D; the next test describes the difference between the two cameras, the practical results and how silent shooting compares to MLU. All the images are highly magnified crops of photos taken at 1/6 f/3.5 with the Sigma 180 Macro. Remember that when the LV is active, the mirror is up, and the shutter is open - this is true for both cameras. 

All cameras - no Live View, no MLU : when you press the shutter release, the camera 1) raises the mirror 2) opens the shutter for the time necessary for the exposure 3) closes the shutter to terminate the exposure. The steps 1 and 2 creates some vibrations, that may result in blurred photos, with slow shutter speeds.

All cameras - no Live View, MLU active : when you press the shutter release for the first time, the camera 1) raises the mirror; when you press the shutter release for the second time, the camera 2) opens the shutter for the time necessary for the exposure 3) closes the shutter to terminate the exposure. The step 1 creates some vibrations, but you can wait few second before pressing again the shutter release, so the vibrations are eliminated. The steps 2 and 3 may still create minor vibractions, even though usually they are negligible.

Canon 40D with Silent Shooting Disabled, or Canon 1D3 : when you press the shutter release, the camera 1) closes the shutter 2) opens the shutter for the time necessary for the exposure 3) closes the shutter to terminate the exposure 4) opens again the shutter to come back to Live View. The step 1 creates relatively strong vibrations, and the steps 2 and 3 may still create minor vibractions. With the 1D3 (or the 40D in this mode), even though the mirror is raised, you can still get motion blur. If you have the 1D3, I recommend to exit from Live View just before the exposure and shooting with MLU active, to get the maximum sharpness with slow shutter speeds.

Canon 40D with Silent Shooting Mode 1 : when you press the shutter release, the camera 1) resets the sensor and begins the exposure 2) closes the shutter to terminate the exposure 3) opens again the shutter to come back to Live View. The 40D has an electronic shutter, other than the traditional mechanical shutter; in SS Mode 1, the only step that may create minor vibrations is 2 (the step 1, instead, does not create any vibration because it is completelu electronic). In practice, with this Mode and Live View active you no longer need MLU - actually, it is even better! It given an even better sharpness, and it does no require to press two times the shutter release and wait, as the traditional MLU.

Canon 40D with Silent Shooting Mode 2 : when you press the shutter release, the camera 1) resets the sensor and begins the exposure 2) closes the shutter to terminate the exposure; when you release the shutter release, the camera 3) opens again the shutter to come back to Live View. In terms of sharpness, this mode is as effective as mode 1; the practical differences are that if you keep pressed the shutter release after the exposure, the step 3 is delayed, so the shutter noise is even more reduced (this is useful if you are photographing a very shy subject and you don't want to scare it with the sound of the shutter release). In SS Mode 2, it is not possible to use continuos shooting.

If these technical explainations sound too complex for you, just remember that with the 40D (but not the 1D3) you no longer need MLU when you are using Live View :-)

Another advantage of the 40D, in comparison to the 20D and the other cameras, if the very quiet shutter release sound, in particular when you shoot with Live View and SS Mode 1 or 2. The next graphs represents the waveform of the shutter sound of a six photos burst (the lower, the better); I've compared the 40D with my previous camera. You can even download the .wav file to hear the difference!

Canon 20D [download]	Canon 40D [download]	Canon 40D - SS Mode 1 [download]

Tethered shooting, Wireless shooting and Video Capabilities

With the USB cable supplied with the camera, you can connect the 40D to your computer, and with the Canon EOS Utility 2.0 software you can change every setting of the camera and download instantly the photos on computer. With the 40D (and other cameras that offer live view), now you can even see in real time the scene recorded by the sensor on your PC screen, you can magnify the photo and focus through the  EOS Utility software. With the wireless transmitter Canon WFT-E3A (that doubles up as vertical grip), you can do the same things without any cable between you and the camera (it has a range of up to 45 meters)! This is an amazing technology, that offers many new photo - and video - opportunities. Even though the 40D does not offer real video capabilities, with a screen recording software you can capture the live view video showed by the camera. The video quality is good, even though it is not spectacular (but remeber that I have no experience in video editing, the image quality of this sample video could be much better). Now it is nothing more than a curiosity, but I think that photo and video cameras are coming closer and closer to a merging - maybe the next generation of cameras will offer real video capabilities?

A short video captured with 40D, Canon Utility 2.0 and screen recording software. You need the latest version of DivX codec. [click here to download]

A SLR with real video capabilities would offer big advantages in comparison with amateur and middle-range camcorders - first and most important, the possibility to use high-quality inter changeable SLR lenses! Usually camcorders lack of real wide angles, and professional wide-angle may cost thoushands of $ - with a SLR and a $400 lens as the 10-20mm, you could get the same angles of view at a much lower price. Other than that, SLRs should be able to offer much better image quality than amateur camcorders, thanks to the large sensor.

Other Improvements (in comparison with 20/30D and other DSLRs)

* The body is quite small and light (nearly on par with the 20D); it is much lighter and smaller than 1 series cameras. I really like the cameras without built-in vertical grip as the 40D, it is much easier to carry around, and the ergonomics are excellent.

* Larger viewfinder: while the photo coverage is the same of the 20D, the viewfinder is clearly larger (and in my opinion it is also a little brighter). It is not as large as the 1Ds3 or 5D viewfinder, but it is very close to the 1D3 viewfinder. Another nice improvement is that it shows the ISO setting.

* The remote release/flash/USB/video rubber door is really improved in comparison with the 20D - with the 20, it was pretty awkward to open, and even more difficult to close. Now, it is a breeze to open it when I need to connet some cable, and it is easy to close.

* Support for 16 GB and larger Compact Flash cards. As you may already know, I don't like to have many CF cards - I believe that having many CFs increases the risk to lose one of them. I prefer to have few high-capacity CFs: the flash memories are very reliable, and it is extremely rare that a CF fails, so I don't worry about putting all my photos on a single CF. I'm going to buy a Sandisk 16GB Extreme III, and I'll upgrade to 25-40 GB CFs when they are available. 

* Improved Compact Flash write speed: currently (september 2007) the 40D has the fastest write times of every Canon Camera (it is even faster than the professional 1D Mark III).

* The new autofocus module now features nine cross-type AF sensors (up to f/5.6), and the center point acts as high-precision point up to f/2.8. I have not done any scientific test, but the AF feels a little faster than 20D AF. I'd have preferred an AF system that worked up to f/8, but I did not expect it, considering the price range of this camera.

* Another feature common to all new Canon, since the 400D, is the anti-dust - a system that shakes off dust from the sensor.I've never considered the dust a serios problems - even with my old 20D that has not anti-dust, I've never had particular problems, and I've had to clean the sensor just few times. Anyway, the new anti-dust is a welcome feature :-)

* Continuos shooting at 6.5 FPS x 17 RAW. While the difference between the 5FPS of the 20D and the 6.5 FPS of the 40D is not huge, it is a nice improvement. The buffer instead is a big improvement - the 20D had just a 6 RAWs buffer, that sometimes was too short, while the 17 RAW are more than enough. By the way, the shutter release sound is much less loud than 20D's strong "tlack!".

* Intuitive, easy to use menu system. The 40D has the same excellent menu system of the new 1 series (even though of course it has not some of the most advanced option of the 1D3 and 1Ds3). The navigation is easy, fast and intuitive, thanks to the clear icons and the excellent interface - you can navigate between the option using the joystick and the main control dial, and you change the settings with the "Set" button. The custom functions are now ordered into four categories; there are 24 functions to customize every aspect of the camera. Another feature that I love is the new "My Menu" (the last menu page, marked by the green star icon). In this page, you can record every setting that you want, to have fast accesses to the setting that you use most often. 

* Very large, big, bright LCD screen! The 3.0" LCD of the 40D is the same of the 1 series, and it is truly awesome. In comparison wih the small 1.8" screen of the 20D, it looks huge! Moreover, it is easily visible even in bright light, and it has a very wide viewing angle. Truly awesome :-D

* The three custom user modes C1, C2 and C3. In every C mode, you can create a "version" of the camera for a particular purpose. For example, an advantage of C modes is that there is no longer need to find the MLU between the menus - you just have to register it into the C mode that you want to use as macro or landscape mode, then you will be able to activate it immediately by selecting that C mode. (note, regarding MLU: remember that if you use Live View you no longer need MLU; you may need MLU only if you don't use Live View)

* Very good JPEG quality and noise reduction. Honestly I don't care much about JPEG since I always shoot RAW, but it is worth to mention that the JPEG quality is very good, and it can be fine-tuned in every aspect. Moreover, the camera offers a very effective high ISO noise reduction (that can be activated through a custom function), that really improved the image quality even at high ISO. The following 100% crops compare the RAW and JPEG image quality at 3200 ISO.

RAW, no noise reduction		RAW, noise reduction with Photoshop CS3
JPEG, no noise reduction		JPEG, in-camera noise reduction

* Some things that were already excellent in the 20D had not changed: as it predecessor, the 40D has a range of shutter speeds between 30" and 1/8000, and an X-sync of 1/250 (and hi-speed flash on all shutter speeds with EX flashes, as the recent 580EX II, that has shorter recicling time than the 580 and it is weather sealed). The user interface is similar to the excellent UI of the 20D, even though the position of some buttons had changed, and of course the screen is much bigger. Last but not least, I'm glad that the 40D, unlike the 5D and 1 series, has a small built-in flash; it is not very powerful, but sometimes it is truly useful.

What I miss and what I don't like...

* A real weather sealing: the 40D has just some quite useless seals on the battery and CF door; I'd really like to see a true weather sealing on par with the Nikon D300 and Olympus E-3.

* A wider exposure compensation range: +/- 2 stops is a pretty narrow range; I'd prefer +/- 5 stops (even the cheapest Nikon cameras offer a +/- 5 stops compensation range).

* An advanced battery, as the one used in Nikon D300 and D3 cameras and Canon 1 series, that show the remaining charge in percentage, and indicates when the battery has reached the maximum number or rechargin cycles and it is time to replace it.

* On-demand grid lines into viewfider! Nikon puts this feature in nearly all its cameras, while with the 40D you have to buy an optional focusing screen with grid lines. The difference is not just price - with Nikon cameras you can turn on or off the grid lines when you want, while with the Canon cameras you have to change the focusing screen.

* Compact flash UDMA Support: even though the write speed of the 40D is already pretty good, the new Nikon and Sony cameras are about three times faster, thanks to UDMA support.

Image samples

The following samples show the image quality of the Canon 40D at the lowest and the hightest ISO settings. The photos had been taken in RAW format and converted with Photoshop CS3; I processed them to optimize the image quality (contrast, color, sharpness), and I saved them as high-quality JPEG for web display. You can download both the processed JPEG and the original, untouched RAW file.

Click on every image to download the full size JPEG sample, or use the RAW link to download the untouched RAW (large files!). Please respect the copyright! These images can be printed only to evaluate the quality of the camera, for personal purposes. All other usages are prohibited.

Still Life - 180 Macro, ISO 100, 1/6 f/9 [ JPEG / RAW ]	Julia The Cat - 24-105 IS, ISO 1600, 1/125 f/8  [ JPEG / RAW ]

A Comparison: why I prefer the 40D to 1D2n

Many times I'm asked why I bought a 40D instead of a professional 1 series, as an used 1D2n. Personally, I think that overall the 40D is a much better camera; here I compared the main features, and I highlighted in green the advantages of each camera.

Conclusion

The Canon 40D has many improvements and new technologies that makes it one of the very best cameras ever produced by Canon. The image quality is as good as it gets in this price range - not a big jump in comparison with the 20/30D (more resolution but slightly worse noise), and it can not compete with super pro SLRs and the 1 series or the Nikon D3 - but still very good, it is fully usable in the entire 100-1600 ISO range, and even 3200 is usable after a little of noise reduction. Live View, Silent Shooting, fast AF, and increased shooting speed makes the 40D a much more powerful and flexible tool than its predecessor; the only thing that I really miss in this camera is a real weather sealing; other than that, for my esigencies it is perfect! I highly recommend the Canon 40D to every nature photographer, unless you have a very high budget to afford both a 1 series and professional lenses.

Do you have comments or questions?

If you have comments or questions about this article, feel free to ask in the Juza Nature Photography Discussion Forum!