Dust and dirt in digital cameras is a huge and largely ignored problem. Added work and lack of sleep aside, it forces photographers to compromise their photography by catering to the ridiculous and restrictive whims of finicky equipment. Changing lenses is now something to be concerned about! Some photographers even carry two cameras with different lenses attached so they don’t have to risk changing lenses in unclean surroundings. Now that we don’t need to carry two cameras in order to have two different ISO films at our disposal, we need to carry two incredibly expensive cameras and restrict ourselves to two lenses so our digital sensors won’t get dusty. What progress! Some even say they try to change lenses only in their vehicles when out on a shoot! Isn’t “digital” supposed to be more convenient? All we need now are portable clean rooms to use in the field.
.
On top of all this, you have a big problem if you need to take a commercial aircraft to a photo location. The ultra-pure methanol used to clean digital sensors is extremely flammable and cannot be carried on commercial aircraft, and it is not readily available in most locations. You can buy some and ship it to your photo location in advance, or simply cross your fingers and give an offering to the god of dust. If luck is with you, you won't have to spend too many hours cloning out dust spots when you return home. How convenient.
.
Warranty: Since you can completely destroy your camera while cleaning its image sensor, you will void your Canon warranty if you clean it yourself. Ship it back to Canon for cleaning every week or so, or every day if you’re in a dusty location, and it may come back slightly cleaner than when you sent it in. Do you think this is ridiculous and not at all practical? Tell it to Canon. Nikon is more lenient about warranty coverage.  For those who want to clean image sensors themselves, Copper Hill Images provides great instructions and a simple but effective tool.
.
Exposure: Whenever possible I bracket film exposures by plus and minus 2/3 of a stop. Most of the time the first exposure is the correct one. Sometimes it’s one of the brackets, and once in a great while I’m so far off that none of them are right. Still, on critical or rare shots I agonize over whether I got the exposure right. With on-camera histograms and flashing highlight pixels I looked forward to knowing with absolute certainty that I got everything right. Sadly, all the gadgetry doesn’t really make much difference. While on-camera displays prevent terrible exposure mistakes, they do not help with subtle exposure errors in the range of 1/3 or 1/2 stop. Shooting RAW files gives you the ability to correct some exposure error later when the file is processed, but digital cameras have absolutely zero tolerance for overexposure when shooting JPEG files. It is common to discover that some fine details are overexposed when a photograph is viewed on a large monitor, even though it and its histogram looked great when it was viewed on the camera’s LCD. Some details are simply too small to show up as flashing pixels on the tiny display. Since they are small they do not shout at you from the histogram either. Bracketing is certainly not dead, it’s just cheaper with digital. The bad news is that, at this writing, only a few digital cameras can bracket at more than three frames per second. If you are shooting wildlife it's just not fast enough. Film cameras have been shooting between seven and ten frames per second for many years. The moral of the story is to always shoot RAW files, not JPEGs, and be extremely careful about burning out highlights.
.
Speed: Speed makes a big difference when photographing birds in flight and running animals, or when bracketing exposures on anything not likely to stay still for a long time. A $2,000 EOS 1V film body shoots at a maximum of 10 frames per second for 36 frames. A $7,000 EOS 1Ds digital body shoots at a maximum of 3 frames per second for 10 RAW frames . A $4,500 EOS 1D MkII body shoots at 8.5 frames per second for 20 RAW frames. Enough said. 

Cost and Obsolescence: When film was king the lifecycle of camera models was long, usually between five and ten years. Differences between models were limited to things like metering, frame rate, auto-focus, and the like. Any film camera that could hold the film flat and had a quality lens could be loaded with the latest film and used to take excellent photographs. The act of getting a given photograph might be easier with a newer model, but comparable photographs taken on any good film camera were essentially indistinguishable from one another. This is why, until now, older professional camera models retained a large percentage of their value on the used market. Now that the film (a digital sensor) is an integral part of the camera, everything has changed. You can't upgrade your film without replacing your whole camera. Rapidly advancing electronics technology dictates that today’s expensive digital treasure will be nearly worthless in just a few years. This is significant, since top of the line digital cameras are more than triple the cost of their film counterparts. Of course some of the cost is offset by savings on film and processing. It all depends on how much you shoot. Just don’t forget that digital cameras require you to invest thousands of additional dollars in memory cards and other obsolescence prone technology.
.
Fragility: Film and professional film cameras are tough. Compact flash memory cards and professional digital cameras are tough too, but unless you invest a million dollars in CF cards you need to download your images to something. The only reasonably fast something at this time is a fragile hard drive. Drop it or give it one too many bumps and every image you’ve taken on an important trip can be lost. Of the thousands of rolls of film I have shot from Alaska to the steamy jungles of Borneo, I have lost only one roll to an accident that involved a wasp inside my shirt, a flying roll of film, and a bit of pain. Had I been holding a portable hard drive or notebook PC at the time, several thousand images would have been lost. Short of theft, losing every roll of film on a trip is unimaginable. Insuring the survival of your digital images involves expensive redundant equipment and the ability to carry it all.
.
Quality: A 4000 dpi, 130 MB scan from a Fuji Provia 100 slide beats a six mega-pixel digital SLR image when it comes to making large prints. At ISO 400 and above, the 6 mega pixel digital SLRs win the print quality contest, but things even out if you clean up the film scans with noise reduction software. This gives high ISO film scans quite a quality boost. Of course to get the 130 MB scan you need to shoot the film, get it processed, and scan the film. This is obviously much slower and more tedious to accomplish. New 8 mega-pixel professional SLR cameras may well beat 35mm film for large print quality at any ISO setting, but since they cost well over twice as much as the best pro film cameras they ought to do something better.
.
Cheer up digital buffs. All of the shortfalls I've written about here will lessen or vanish as time passes and the technology improves. In fact, this article (along with your camera) may be obsolete by the time you've read it. The huge cost differences between film and digital begin to shrink if you shoot hundreds of rolls of film per year. Using a digital camera greatly streamlines the workflow at home after a trip. Unfortunately it adds greatly to the work which must be done in the field when it is least convenient. To its benefit, grain or “noise” is a thing of the past at speeds less than ISO 400. You can change the ISO setting for each frame independently. Nearly immediate feedback is a wonderful learning and creativity enhancing tool. Digital cameras are capable of capturing far greater shadow detail than scanned film. Digital capture eliminates the long and laborious hours of film scanning. Best of all, digital cameras are fun to use. Even if it can’t yet live up to all of the hype, “digital” is here to stay and it offers some new and unique possibilities. At the same time there are those who will continue to make wonderful photographic images on film. The digital age should not pretend to take anything away from great old photographs, or great new photographs made with film and smelly chemicals. The greatness of an image does not depend on the tools used to make it, and photography is about making great images.

June 2004 Update
After only a few months of use, one of our SanDisk 1GB Extreme CF cards failed while shooting in the jungles of Malaysian Borneo. Apparently it wasn't extreme enough. Reformatting the card failed to fix the problem. Finding this out took lots of time because the problem occurred only when the card became about 3/4 full. Otherwise it worked fine, and we were able to retrieve all of the images except one. Upon returning home and contacting SanDisk technical support, we were told that the card must be replaced. That takes about two weeks and involves getting a return authorization, packing and shipping the product, and waiting for the new card to arrive. To their credit, SanDisk makes this process as easy as possible and their "Extreme" cards have a lifetime warranty. Still, nothing like this ever happened with film. Screwing around with cables and computer equipment, formatting CF cards, copying files, and worrying about the integrity of the images I've made while sweating like a pig in the jungle isn't my idea of a good time. Am I nit-picking?
.
August 2004 Update
Sometime before its warranty expires, our Canon EOS 10D will make a trip to Canon's service center in New Jersey to have a single stuck pixel "repaired". The pixel is about 1/6 of the way up from the bottom of the frame and  just left of center. It is always bright regardless of the background. I am told by Canon Professional Services that the fix usually involves substituting adjacent color values for the defective pixel. This is essentially in-camera cloning and not a true repair of the defective pixel. I see no problem with the repair method. After all, one pixel is smaller than any dust or other imperfection that gets cloned out of images on a regular basis. The only reason for repairing it at all is to keep from having to clone it out of the images later on. While the problem is so small that it's almost not a problem, it's something that doesn't happen with film, ever. There are no stuck pixels on our EOS 1D Mk II, yet, but there are a couple on our little Olympus point & shoot digital camera.
.
As long as I'm complaining about digital idiosyncrasies... I was recently reminded by a friend that there are certain types of images that simply cannot be made at all with a digital camera. For instance, try taking an hours-long exposure to get star tracks in a photo. Without post processing, even a ten minute exposure to get light trails on a desert highway will exhibit plenty of noise. Then there's infrared photography. Without extreme camera modifications that make the camera useless for normal photography, it simply cannot be done. With a film camera you need only buy a filter and roll of infrared film. Digital image capture offers some incredible advantages, but there are some incredible disadvantages too. Digital camera technology is simply not yet as rugged, reliable, and hassle free as film camera technology. Until it is, I'll continue my love-hate relationship with digital image capture and there will be at least one film body along on most of our travels - if for nothing more than its depth of field AE mode.
.
For you cold weather shooters, let's not forget that cameras like the EOS 1V are rated to work at temperatures down to -20°C (-4° F) while all of Canon's digital cameras are rated only down to 0° C (+32° F). If you want to stay within Canon's design limits and take photos in the winter, you'd better live in the south or stay inside! Many people seem to forget about this limitation, but Canon's top technical representatives have not. They make no apologies for it, saying the temperature limitation is simply a limit imposed by the currently available battery, LCD, CF card, and other technology. Some people do successfully use digital camera bodies at colder temperatures. They usually work, but sometimes serious operational problems result. In addition to LCDs freezing and sometimes not returning to normal on warming, and the expected battery problems, I have heard accounts where the shutter button and other controls work intermittently in the cold. There's one account of a bright arc appearing across every image after a camera was in 15° F (-9° C) for two hours. I do not mean to pick only on Canon here. Nikon and all other digital camera brands have similar design limits. Regardless of the brand you use, film bodies keep taking pictures reliably at the temperatures where all of these digital camera problems occur.
.
I am sure many people who read this will say "I've used my digital camera in very cold temperatures and it worked fine". As I said earlier, they usually do. But, the fact remains that temperatures below freezing are beyond the design limits of these cameras, so you cannot count on it working reliably at these temperatures. Would you risk an important cold weather shoot on the chance that a digital camera might work in temperatures it was never designed to handle? This seems much like using a rope rated by its manufacturer to carry one hundred pounds for lifting something that weighs one hundred thirty pounds. The rope usually won't break, but if it does you have only yourself to blame.
.
Another August 2004 Update!
Just over four years ago Canon's D30 was the latest thing in digital camera technology. Since then we have seen the D30 and its successor the D60 fade into obsolescence. Now obsolescence rears its ugly head over Canon's EOS 10D camera in the form of the just announced EOS 20D. It is the fourth digital camera to fill this spot in about as many years. The new camera is a smaller and lighter, 5 frame per second, 8 mega pixel version of Canon's 6 mega pixel, 3 frame per second EOS 10D, and it carries the same price tag. This is great news if you have not "gone digital" yet. It's not such great news if you just bought an EOS 10D, which is now worth a fraction of what you paid for it. But cheer up. Misery loves company, and the same thing will happen to all those EOS 20D owners in a short while. Now that cameras are computers, their lifecycles are incredibly short. Since the 20D form factor is completely different than the 10D, it uses a different power grip. If you use any Arca style L-brackets or mounting plates, you’ll have to replace those too. 
.
Initial reports are that the 8 MP sensor’s noise figures are the same as the ultra-low noise figures of the EOS 10D image sensor. That’s quite a feat considering the fact that the 8 mega pixels are packed into the same physical space, and hence produce the same 1.6X magnification factor. If this were film you could simply buy a few rolls and try it out. As it is you'll have to plunk down about $1500 in order to give it a spin. The good news is that this new camera may be able to produce large prints that are as good as those from film. Still, the incredibly short life cycle of these cameras will make us all experts at doing EBay auctions and depleting our bank accounts.
.
November 2004 Update
The end of the film era looms large, for us anyway. We have decided to sell the last of our film equipment. See why in this article.