Canon EOS 40D 10.1MP Digital SLR Camera (Body Only)
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Digital Cameras Photo Reviews of Canon EOS 40D 10.1MP Digital SLR Camera (Body Only)
Customer Review: Canon 40D -- What I like... What I don't like
Summary: 5 Stars
I was a long time owner of the Canon 10D which I quickly outgrew. Then, I upgraded to the 20D and have been using it for the past few years. I didn't think the 30D was a big enough step forward to warrant the upgrade. Going from the 20D to the 40D is a big leap forward.
Unboxing the 40D is about the same as the other two DSLRs I've owned. Manuals in both spanish and english, plus software for MAC and PC. I got the "body only" package as I already own the 28-135mm lens. That lens is just **ok.** and I really didn't want a 2nd copy. The battery is the bp511A so I can use the already charged one from my 20D. The strap is the same as the 20D. The compact flash memory is the same as well, so I didn't need to buy any new accessories to upgrade.
The first thing you will notice is the big display on the back. It's very nice compared to the one on the 20D. Although, I'm constantly afraid that my titanium rimmed glasses will scratch the screen. The screen is so much closer to the viewfinder compared to the little one on my 20D. I think I'll look for a clear film cover that will shield it.
The controls are very similar to the 20D/30D. However, they are moved around a bit. The menu structure is very different and it will take some getting used to. The first thing I thought of was my old 10D... and how simple it was just due to the sheer lack of features. The 40D has so many that it would be tough for a beginner to get used to them all. It might be good for beginners who are a bit techno challenged to buy a cheaper, used DSLR to get used to using a simple model... then sell it and upgrade.
The camera feels so much more solid than my 20D. The little motor that pops up the flash sounds really solid compared to the old 20D. Even the shutter sounds terrific. Very quick and quiet. The old 10D had a nice shutter sound as well. the 20D always sounded like thrashing metal to me. To contrast, the Nikon DSLRs have a slow sounding swish to them... this one is tight and quick. The camera feels about the same in my hand. Although the lines are smoothed out a bit compared to the 20D.
I tried out the live preview feature and found it annoying since I'm used to looking through the viewfinder. I think I would like it much more if this was my first DSLR as a conversion from a point and shoot where you typically only use a "live view." The LCD is viewable at a strong angle so the live view may be usable for when the camera must be held at odd angles away from the body... like over a stream or something. This camera is heavier than a point-and-shoot and you need your face to help you hold it steady. I found myself a bit wobbly when I was holding it out using the live-view feature. You'll need a high shutter speed to keep from getting shaky looking pictures.
So, what about picture quality?? It's a 10mp camera so the pictures are big. I have a workhorse MacPro tower and it has no problem working on the 10-12MB pictures that this camera produces (.jpg processing for now). I'm happy to say that the focus is spot on in all of my sample pictures from 4 different lenses (17-40 f/4L, 28-135 IS zoom, 50mm f/1.4, 100mm macro). The DPP software can be used to edit raw files if you choose to use it. It works pretty well and it was very speedy on my MacPro. You also get direct access to picture styles from within the computer software so you don't have to worry about setting it in camera. The pictures look very nice. The colors are very accurate. at iso100 the pictures are so nice and smooth. My 50 and 100mm lenses make the most buttery out of focus areas on this camera.
******ALERT******
as of this writing(9-2-2007), Aperture, Finder, Preview, Photoshop CS3 (ACR4.1), and iPhoto do not support raw image files from the 40D. This was the case with the 10D when I first purchased it and it took a few months for APPLE and Adobe to deliver updates. I'm sure Canon are working hard with vendors to get their updates in the works. The good news is that there are settings for RAW+.jpg so you can have both files when the software updates come through. If you don't like being on the "bleeding" edge of technology, then wait a few months before you plunk down the cash for the 40D.
***** ALERT UPDATE *****
As of 9-13-07, Adobe has released Camera Raw updated 4.2 which now supports the Canon 40D.
As of 10-26-07, Apple's Aperture and Mac OS 10.5 (Leopard) support Canon 40D raw files.
Picture styles are easily accessed from a dedicated button on the camera. They allow you to make quick sets for defining different picture taking scenarios. It basically does some basic post-processing work in-camera to save time later. It worked really well. I found that pictures even up at 1600iso looked usable for every day stuff (e.g. not blown up too big.). ISO can be set in 1/3 stop increments which is new for me. having iso250 just seems weird but it's actually very handy. Gives you the ability to really tweak the settings to capture as much detail as possible in a high dynamic range image (like a sunset, or a backlit portrait without fill flash). I haven't taken side-by-side shots yet but it seems like the images are more detailed with a wider dynamic range than the 20D. Maybe this is the 14bit image processing from DigicIII at work?
The camera seems more responsive than the 20D. The menu scrolling seems faster, file writing seems about as fast (probably a faster rate but bigger file).
One of the neatest features is the custom C1, C2, and C3 dial positions. You can set these up to "remember" camera settings for quick access later on. They act like the memory buttons on luxury car seats! Very handy if you take really different kinds of shots. I go back and forth from Macro to Landscape all the time so I can quickly dial in my base set and go from there.
The vibration dust remover might be a cool feature. I can't feel the camera vibrate or hear it working, which is nice. Apparently it vibrates for 1 second whenever the camera is turned on or off. I changed this setting so that it's only triggered manually by me. I figured I could just use it when I need it rather than have it going all the time. .
Another of my favorite features is the spot meter. The 10D and 20D never had this feature. Apparently the 30D does, but this one is slightly higher weight at the center point. I tried it out and it works really well in combination with the AF point selectors.
So what do I hate about the 40D? I really hate the Auto White Balance setting for indoor shots. You want to be sure to set the camera manually when you are taking the 50millionth picture of your dog. Otherwise it'll be all yellow looking. Canon, can you fix that please?? If you set it manually it looks great.
SInce I like to do available light photography I like to use mirror lock-up. I wish there was a button for that as do many other people.
Canon finally has the iso setting in the viewfinder so we'll give Canon props for that.
My last gripe is that the display screen could have a bit higher resolution. It's nice and big but could have a denser pixel set for really checking out your work.
Overall I'm sure anyone would be happy with this camera if you are willing to spend the time to learn how to use it. If you are a beginner, don't expect to take magazine quality shots on day 1. Wait at least till day 2 :-)
I must say that Nikon did come out swinging this time. The newly announced D300 is quite the camera. It will be interesting to compare the Sony CMOS pics to those produced by Canon. Had I not had a bunch of Canon gear already I might have given up the extra dough for the Nikon. Nikon (Sony) blues and reds always seem too punchy to me but that's just my personal taste. My good friend has a Nikon D200 and his pictures are just beautiful out of that camera. The Nikon D300 has some wiz-bang features but I'm not sure I would take advantage of them... nor do I think they will directly result in better pictures. Spend the $500 bucks you'll save on a photography class and you'll have more fun, meet more people, and be taking better pictures at 3 months than if you start with a really fancy camera that you can't figure out how to use.
I'm hoping Canon has been spending some time re-inventing as Nikon have over the last couple of years. The good news is that all of these cameras take good pictures; however, you have to know how to use them. When I pick up my friends Nikon is seems all foreign to me and I feel out of my element. He makes the same comments when he uses my Canon.
Customer Review: The Most Camera For Your Money
Summary: 5 Stars
The Canon 40D is the most camera for the money that Canon has ever provided. The highlights:
- The new improvded Autofocus: Yes, it's still 9 point, and I was skeptical about how improved it would actually be, but having used in the field on several photo shoots, I was able to compare it directly to my Canon 5D, and the AF on the 40D was noticeably more accurate & sensitive to subtle differences within the Depth of Field. The new system performs especially well with my 135mm 2.0L, and my 70-200mm 2.8L IS. But this is what is advertised about it (i.e. better performance with lens w/ Maximum apertures of 2.8 and greater).
- The 3.0" LCD: Once again, comparing this to my 5D, which has a 2.5" display, the color reproduction is noticeably more accurate. Initially I thought that the colors were being captured differently by the camera, but when I realized they were very similar once I looked at them on the computer, it became apparent the difference was in the display on the camera. Also, the display on the 40D is brighter. I have not yet noticed as dramatic a difference as Canon has made it seem in their product detail when viewed in sunlight, but especially in darker settings, it is noticeable that there's a difference.
- The frame rate & buffer size: The increased buffer is very apparent, in particular at the low speed continuous setting (3 fps), where the speed at 3fps seems faster than the 3fps on the 5D simply because it can continue shooting (seemingly endlessly). In the high speed continuous mode (6.5fps), the speed is mind-boggling. I have not had a chance to fully test this out yet (look for a future edit to this).
- The viewfinder: The size and brightness are noticeably & dramatically better. The look through the viewfinder is so improved over my old 20D, they almost can't be compared. It's not quite as big as the 5D, but not far off either. And it's just about as bright as the 5D, if not as bright.
- The AF button on the back: Although I still use the regular half push on the shutter button the majority of the time, I have found the rear AF button to be very handy at times. At certain times, the way in which I hold the camera makes using the traditional half push much easier. However, as a tip, I have found that in focus-recompose situations, the rear AF button is invaluable, as it is MUCH easier to continue holding down the rear AF Button while recomposing and then snap the shot, whereas with the traditional system, it is more difficult to recompose without accidentally releasing pressure slightly on the shutter and having to try again (or accidentally taking the shot after it refocuses to an area you didn't want).
The menu system: The new tab based menu system is much more intuitive & much better than scrolling through one big list. If you've ever seen the menus on some of the more recent Powershot mini point and shoots, it's like that (similar specifically to my knowledge to the SD630, as that is the one I own).
Battery management: I used this camera at the Redskins/Dolphins home game last week, and I have a routine of where and how much I take pictures, and how often the camera is on. My camera came in the day I had a photo shoot with a model later, so I put in a battery I had already charged to use with my 5D, and left the brand new battery to charge at home. So, I was using one of my old batteries, in other words. This was not a long photo shoot with this model, I shot maybe 50 pictures of the shoot with the 40D. I never changed the battery before the game & what was noticeable was that the indicator did not drop off of "full" until the end of the fourth quarter, right before they went into OT. Since I was shooting with a new 40D as opposed to my old 20D I was shooting more, also - probably 33% more than normal. And with the 20D, if the battery had just been charged and no other use, it would have been down from "full" by halftime, slightly beforehand. The camera is clearly managing the power consumption better. (NOTE: The one improvement that did not make the 40D, disappointingly, is a better battery indicator - it's still the same annoying little 3 bars, of which 2 always go away when it drops from full, so really a two bar indicator).
- The speed of scrolling through pictures: I know this has to be a result of the DIGIC III processor. It's absurdly better than the 20D or the 5D. If you scroll the knob real quick to zip through a bunch of pcitures, it's there in a second or less. The best way I can describe it is the difference in a computer that you'd been running 256MB RAM on & you just upped it to 1GB. It makes the "Jump" button seem almost unneccesary, however, I'm glad that it's still there!
- Picture Style Button: This is very convenient. I hated looking for that through the long menu.
- Flash management: I don't have the new 580EX II yet, but with the 580EX, it's still noticeable that when using the E-TTL automatic mode, it does a better job of managing the output, using a lower output at times when I know it would have overfired or drawn more power on the 20D, and the end result is you can get more good shots quicker. NOTE: I was using the external power pack also. But I'm making my assessment based on use of the power pack with the flash when using the old camera as well.
- Visible ISO on the display on top. And better, although still familiar, layout on the top display.
Assessment: In terms of specs, this camera is amazingly close to it's new big brother the 1D Mark III, more than past models have been. This is a big plus to those of us who don't have a fortune to spend on the top of the line Canon cameras. The image quality of this camera is not noticeably different than that in the 5D, although there is a slight difference when you look carefully. And of course it isn't full frame, which is a minus in certain applications, and a plus in others. The improvements between the 20D and the 30D were negligible, to say the least - it was clear Canon was just extending the lifecycle of the 20D, and the 30D should have been called the 20D Mark II. However, the 40D has many dramatic improvements over both of these previous models, and scrapes at the heels of the 5D in all of the areas where the 5D once had a clear advantage - let's hope for a 5D Mark II (or 7D, or whatever it will be called) soon. I've been reading rumors that it will be the 1st quarter of next year. I will admit that when this camera was first announced, and the Nikon D300 announcement came a few days later, Nikon caught my attention big time. But obviously, with all my investment in so much Canon equipment, it was a no-brainer to continue with Canon. Even to own both brands would be a considerable additional investment for that one body, as I have no Nikon lenses. At this point I will preach the gospel of "L." To truly appreciate how good Canon photography can be, you need to own at least one "L" lens (although it will become more than one once you do, LOL). I own the highest rated (and still somewhat "affordable") L lenses, the Canon EF 135mm f/2L USM Lens for Canon SLR Cameras, the Canon EF 70-200mm f/2.8L IS Image Stabilizer USM AF Telephoto Lens & Filters & 5 Year Warranty & Accessory Kit(both previously mentioned here), the Canon EF 100-400mm f4.5-5.6L IS USM Telephoto Zoom Lens for Canon SLR Cameras and the Canon EF 24-70mm f/2.8L USM Standard Zoom Lens for Canon SLR Cameras, which I haven't used on the 40D yet, as I prefer the idea of using it on the full frame 5D for the wider angles it provides. I haven't used the 100-400 on it yet just because I haven't had a chance or the right opportunity. They're all worth every penny, and I would note that the 135mm 2.0L might be the best lens, period. It's defintely my best one, although the 70-200 2.8L IS comes close.
Once again, the 40D is the best body for the money that Canon makes.
Customer Review: A great camera - with room for improvement
Summary: 5 Stars
I'll start off by saying that yes, this really *is* a great camera. I bought it as body only, then added a Canon EF 100 f2.8 Macro USM lens. If you're not familiar with that lens, it is fairly heavy, and so the camera has felt heavy to me since day one. But it is the lens creating that impression.
The 40D starts up, shoots, and shuts down quickly; With the right lenses, it creates clear and consistent photographs; it is hugely flexible, pretty much to any degree you want to flex. Some of the things that have made themselves known to me by how well they work are, in no particular order, the great battery life... I use the LCD a lot, shoot a lot, and generally fuss continuously with the camera, and it just "keeps on going" which is enormously pleasing (this is with the stock battery and a BP-511A spare pack to swap in.) The feel of the camera - just a nice handful of goodness, it really suits my hands, which are large. The clarity of the viewfinder. I wear glasses, and after a little playing with the adjustment, it was *perfect*, first time ever with any camera. This thing is *fast*; it really can do 6 or so frames a second (depends on the shutter speed, of course) and the AF is also fast which makes for more images, and more good images. I love all the preset modes, and I've already had some fun in manual and a *lot* of fun in aperture priority, which pretty much suits the way I think. I particularly like the AF display and the way you can control it; I prefer a single central AF point so I can control focus at the half-press point, and the camera was perfectly agreeable to that. More points did some interesting things with depth of field, and I look forward to experimenting with that, too.
I would buy this camera body again in a heartbeat if something horrible happened to mine, like I dropped it down a well or larval (and soon to be deceased) human beings got hold of it and used it as a kickball. It also offers some optional features like wifi that sound like great fun, though I confess I can't speak to them as I've not tried them.
There are some things I think could have been done better, though, and since you're probably looking at the camera wondering what the downsides are, rather than looking for what made everyone happy, that's what I'm going to focus on.
o The worst problem, by far: The images that the camera uses to let you review your shots are FAR softer than the actual photos, to the point where you can't really tell if you got the focus nailed, or not. This is not a nitpick - this causes me to take extra shots because I literally can't tell if I've hit the mark, or not. I am hoping this can be fixed with a firmware update to the camera.
o That fabulous LCD, huge and bright and crisp, looks awful every time I look at it after shooting through the TTL viewfinder. This is because it has a huge NOSEPRINT on it. Has anyone at Canon ever taken a look at a human face? Placement of the monitor should be offsides and inset so that it isn't a grease magnet. Or do they expect me to wash my nose every time I snap a picture out in the field?
o While I'm harping on the camera's ergonomics, the power switch isn't very easy to manage. I have very short nails (I'm a guitarist and a martial artist, neither of which encourage nail growth) and getting that switch to swing on and off sometimes takes more than one try; that may, someday, lose me a photo I really wanted, especially considering how fast the camera starts up otherwise. I really wish it had a deeper pit for my finger and a more positive tractive surface to drag it on. It's too short and too smooth.
o When in Live View mode, meaning, you're presumably shooting using the LCD instead of the viewfinder (after cleaning your latest noseprints off of it, of course), autofocus doesn't work. But wait, it does. *If* you press a different button. Apparently the power budget of the camera is pushed a little too close to the edge if you use live view *and* autofocus because the mirror is locked in the up position. So they... moved AF to another button? Look, either let me do it, or don't let me do it, but quit changing what the controls do underneath my fingers. That's just poor interface design. Maybe you should have turned it off by default, then let us blatant power-spenders turn it back on, kind of like how ISO 3200 works on this camera (it's a menu option, not initially enabled. Requires RTFM or at least someone telling you what to do.) Anyway, I don't like how this works. At all. But it's a nitpick.
o When you're not in live view mode, the camera will display your shot in the LCD for 2 seconds, then blank (this time is adjustable, somewhat, in the menus. But 2 seconds is the shortest time for it to work at all.) You have to wait for the preview to go away (2 seconds) to enter play mode so you can really take a look at it. I think it should directly enter play when it is in that 2-second "grace" period after the shot; the fact that it doesn't costs me time, at least in some situations. And time, in photography, can mean lost shots.
o Print button - come on. I can think of a hundred things that would be more important to put on a button than "print." That's just... silly.
o I would have liked to have infrared remote firing of the camera. This is MUCH more flexible than the 2s or 10s delayed firing option it has now. You can go out and sit with a group and putter around indefinitely with infrared; even 10 seconds isn't a lot of time to get out there, regulate your breathing, meld into the group photo, and stop staring down your 3rd cousin Hotisha's bodice. Uh, not that I would do such a thing. No. Not me. Cough.
o It isn't easy (meaning, you have to use a deep menu) to clean out all the images on the CF card. Should have been, really. it *is* easy to delete images one at a time.
o The weather flap on the USB connection (and external fire, strobe, and video connectors) are a little difficult to grasp (I have essentially no nails, remember), and they really are just rubber flaps - I fully expect them to wear out, as they don't have proper hinges or otherwise use reasonable bearing surfaces. I *really* don't like having to struggle with the flap every time I want to grab pictures from the camera, which is several times a day on days when I'm *not* seriously shooting. I might *have* to buy that wifi accessory...
These are, in the end, mostly problems I would characterize as "nitpicks", and with the exception of the soft review images, certainly nothing to get in a frenzy over (well, maybe the placement of the LCD screen too... but that certainly isn't a problem only found in Canon products.) This is a fabulous camera; I can't imagine anyone actually regretting buying one unless they've been working with far, far more expensive gear than this. I gave it five stars, and that's just how I feel about it.
About me: I've been into photography since about 1965, my last camera was an Olympus E20, a 5 MP camera with an *excellent* all-occasion lens, macro to telephoto, and an insatiable appetite for batteries. Moving up to a 40D was a great experience for me. I'm not a pro, maybe semi-pro is fair, my experience with cameras includes both BW and color developing, all manner of large format boxes, several 35 mm cameras, and ten or eleven digital cameras from the 320x240 dawn of digital cameras to today. I am also an engineer (EE) and the author of a very extensive image processing software suite and several RAW processing plugins; consequently I am intimately familiar with how digital cameras actually work.
Customer Review: Bravo, Canon!
Summary: 5 Stars
I received the Canon EOS 40D on 9/26/07. From the time I took it out of the box and held it, I knew I was going to like this camera.
Ergonomics: I've been using a smallish Rebel XT for almost a year, so the larger size and grip of the 40D was a delight. And the 40D is nice and grippy in all the right places. And all the controls fall readily to your fingertips--very ergonomic.
Build quality: It has some heft to it, which lends a sense of sturdiness and quality. Also, the extra weight provides a better balance for my EF-S 17-55 f/2.8 IS USM lens. My Rebel XT, when I had the strap around my neck with the camera hanging down in front, would tend to twist forward under the weight of the lens. With the same lens mounted to the 40D, the camera tends to stay straight--much better balance.
Viewfinder: The viewfinder is another thing that Rebel XT owners will smile about regarding the 40D. The viewfinder is much larger and brighter than the Rebel XT's.
Top LCD: The top LCD display has lots of helpful information that remains displayed at all times (f/stop in Av mode, white balance setting, est. remaining shots on card, battery indicator, metering mode, auto focus mode, exposure scale, ISO, and shooting mode (single shot, 3 fps, 6.5 fps, or timer)). I look at the remaining shots indication all the time.
Rear LCD: The rear LCD is huge (3-inches). And the lettering is large, bright and easy to read--much better for those of us who have difficulty seeing small writing close up. I find that it can be read even if you turn the camera almost all the way sideways to your face. Therefore, the 140 degrees viewing angle rating appears to be quite conservative. The menu options are well-organized, intuitive, and easy to navigate and use. You can set the amount of time the image displays on the rear LCD after you take the shot (Review time = Off, 2 sec., 4 sec., 8 sec., or Hold). I did notice that, despite how very bright this display is, in bright sunlight, it is nearly impossible to see the image in the display. So, I just had to look for some shade (or shield the display from the sun somehow).
Taking Pictures: The 40D lends so much confidence, it is almost impossible to adequately describe. Especially with the excellent EF-S 17-55 lens, there seems to be no shooting situation you can't conquer. The Auto Focus (AF) locks on fast and sure with a quick "beep-beep" in all lighting situations. I generally have the camera set to just the center AF point, since I want to choose the specific spot I want to focus on. The 40D has a high-precision cross-type center AF point that, when used with an f/2.8 or larger lens, provides twice the sensitivity as the other AF points. Lately I've been utilizing the 40D's Highlight tone priority mode and the High ISO speed noise reduction mode. The Highlight tone priority mode expands the dynamic range from gray to bright highlights and the gradations in between become smoother. This mode forces the minimum ISO to be 200. This is no problem, since the 40D produces very low noise, even at elevated ISO speeds. I have noticed that detail in highlights is well-preserved, though I still frequently need to reduce the highlights in post-processing (I shoot RAW almost exclusively). The High ISO speed noise reduction mode applies noise reduction at all ISO speeds, which is particularly effective at high ISO speeds. This mode also reduces noise in shadows. I am having no problems with noise on this camera. And despite this in-camera post-processing, in Photoshop Elements, I still can level, saturate, sharpen, etc. to my heart's content and still wind up with a sharp image, due to the excellent 10.1 megapixel sensor, and the inherently low amount of noise it produces.
Live View: I briefly played around with the Live View mode hand-held, since I have yet to receive my new ball head I've ordered for the tripod legs I recently received. It is really convenient to move the little joy-stick on the back of the 40D to place the little box over the point of interest and zoom in 5x or 10x and manually focus to fine-adjust the focus. You can auto focus during live mode by holding down the AF On button until you hear the quick "beep-beep" of the AF locking on (rear screen goes blank), then release it and the Live View display comes back on immediately. When you press the shutter release in Live View mode, it is nearly silent, since the mirror is already locked up and out of the way. [Note that you initiate Live View mode by pressing the "set" button in the middle of the big wheel on the back of the 40D and the mirror locks up and out of the way immediately, and you get a nearly full-screen, live view on the large rear LCD with info underneath showing (in Av mode) f/stop, exposure scale, shots remaining on card, and ISO speed.]
General observations: The battery seems to be lasting a long time, despite me playing around with the Live View mode, and spending a lot of time going through menu items and deciding which modes I want to use. As of this writing, I've taken about 200 photos (some of which are posted here for you to see). I got the 8GB Sandisk Extreme IV Compact Flash card, so I can just walk around popping off shots without worry of running out of space. I have received a Bogen-Manfrotto 055mf3 tripod, but I am waiting on the Kirk BH-1 ball head to arrive. Then, I will give the Live View mode a thorough going over.
Conclusions (9/29/07): This camera simply does all that is asked of it. There is no better camera that can be used with the top-performing Canon EF-S 17-55 lens, since the 40D is the best 1.6x crop Canon camera body, and the EF-S 17-55 lens can only be used on 1.6x crop Canons. The 40D is ergonomic, sturdy, feature-packed, high performance, high IQ, low noise, and an exceptional value. I'm sure many pro shooters will be snatching these things up, too. And I'm going to have a ball exploring all that it can do. Bravo, Canon!
Customer Review: A great mid-range SLR for heavy duty
Summary: 5 Stars
Why would you buy this camera when you can buy a Canon 400D or Nikon D40x for about half the price? Or: Why would you upgrade from your current Canon 20D or 30D?
The 40D is more than halfway up the scale that starts with smaller, lighter, plastic-body single lens reflexes like the Canon 400D or Nikon D40x and goes up to the amazingly capable and tough cameras used by professionals. The 40D is a lot less than halfway up the price scale, so depending on how much you use your camera and what kinds of photography you do, you could consider it to be a bargain. If you plan to haul your camera around a lot, you'll like the strong all-metal body, despite the added weight and size. If you want to get the most out of Canon's full-featured external flash guns, you'll like the integrated flash control capabilities. If you want to take a series of photos very quickly to get the best shot of a sports event or a child's facial expressions, you'll like the ability to rip off 8 shots a second. If you want to take photos at night or macro photos - extreme close-ups -- you'll like the ability to flip the mirror up to get the steadiest possible shots on a tripod.
But if you don't think you'll ever use a tripod, you probably don't need this camera.
If you're thinking about upgrading from a Canon 20D or 30D, the 40D has worthwhile improvements. I upgraded from a Canon 20D. I've taken about 1000 photos with the 40D and I'm quite pleased with the improvements. The most useful are the much larger LCD and the "live view" feature. The big LCD makes it a lot easier to judge the shots you've just taken, and it's brighter and more easily visible in sunlight than the LCD on the 20D and 30D. (On the other hand, it doesn't have more pixels, so the shot is not as crisp as one would like.) Live view lets you use the LCD instead of the viewfinder (which you can do with any inexpensive digital camera). That means you can frame and focus easily when you're taking a photo from a very low angle, as you might if you're doing macro photography. And it's great in crowds because it allows you to hold your camera up over the heads of the people in front of you and still see what your camera sees.
The 40D also has a more user-friendly menu than the 20D/30D, and you can specify up to 3 custom settings that allow you quickly change to a combination of aperture, speed, ISO, and other settings that you use frequently. The 40D also has a built-in mechanism that shakes dust off the sensor. (The sensor on the 20D didn't seem to attract a lot of dust, but I'm pretty careful when changing lenses.)
If you buy the camera in a kit with a Canon lens, be careful about what lens you buy. Remember that cameras in this category - under two grand - have sensors that are smaller than the frame of a 35mm camera. Therefore, if you use a 50mm lens, the camera's field of focus makes it look like you're using an 80mm lens. (Multiply the lens' focal length by 1.6 to get the effect on a 40D, 400D, or any of the Nikon equivalnets.)
The 40D may be bundled with an inexpensive 18-55 mm lens that's pretty basic and covers the same range as a 28-80mm lens on a regular film SLR. That's a very usful range -- wide angle to modest telephoto. Or you can get a 17-85mm image-stabilized lens that has a very useful range - equal to 27 - 135mm. But the images need some work on your computer to correct distortion if you're making enlargements of wide-angle shote.
Or the kit may include a 28-135mm image stabilized lens that acts like a 45-215mm lens on these "1.6 crop factor" cameras. As such, it doesn't have enough a wide angle range suitable for landscapes or photos of groups of people. Of the three, I'd choose the 17-85mm. But if your budget can handle it, consider buying the 40D body and adding the excellent Canon 17-55mm image stabilized ("IS") f/2.8 lens, which has to be purchased separately. You might also consider the much less expensive Tamron 17-55mm f/2.8 (which lacks stabilization and is not quite as good as the Canon 17-55.)
If you already have a Canon SLR and an additional lens with a Canon mount, it's a no-brainer to consider the 40D. But if you're buying your first SLR, do take a good look at the Nikon D80 or the Nikon D300, which is more expensive but which has some nice features. And there are also very capable cameras in the same price range from Sony - the Alpha 700 - and Olympus.