35mm vs. 645
Preamble
As far as the average amateur photographer (i.e. any one who does not make the main bulk of his income from photography) is concerned, building a photographic system takes time, money and, of course, thinking - unless money is not an issue. As things used to be, almost all of us would start with a simple 35mm system and gradually, year on year, build it up - every now and then buying useful accessories or lenses that would inspire and expand one's creativity and, maybe, upgrade from, say, a Nikon F90 to a Nikon F100, while continuing to use the same lenses. This, however, has been significantly changed and speeded up with the appearance of digital equipment that can produce high-quality images that could compete on equal terms with the quality of the best films available at that point or even surpass them. As to the change, from being one-time digital skeptics we have started gradually accepting the somewhat uncomfortable fact that film is irrevocably dying (at least in the 35mm format) and wondering if - or, rather, when - to completely switch to digital. And as to the speed, new models and designs now appear - and become obsolete - at a much faster pace; they also cost a lot more than before. As just one example, the Nikon D1 was introduced in early 1999, the Nikon D1H and D1X in early 2001 and the Nikon D2H in June 2003, while the Nikon F90 was introduced in 1992 to be followed by the F100 in only 1998. This goes along with the similarly very fast change from AF to AF-S and then further to AF-S-DX-G lenses, not to mention an even faster pace of change in the "prosumer" digital market. All this, in my view inevitably, should make an average amateur photographer think deeply about his actual needs with respect to photographic equipment so as to address this situation and make a wiser investment that would both provide good image quality and, by the endlessly advancing at an ever-increasing speed standards, last longer than a couple of years. In my case, this situation broadened my outlook towards photographic equipment and raised the issue regarding existing alternatives. In particular, I have asked myself what the relationship between different formats is, what format one should work in or whether, alternatively, one should diversify towards several formats.
35mm vs. 645 vs. any other format - opposition or supplementation?
Different formats are being constantly compared in an attempt to figure out which one is better and provides the best image quality; we also often hear phrases like "moving up from 35mm to 645", "switching to 6X6 format", and so on and so forth. All this almost suggests that different formats are exclusive of each other and one can only work in one format. I, however, am of the opinion that different formats are actually different tools that are means towards different ends and that serve different purposes. Generally, small format offers speed of operation, versatility and convenience; large format offers extremely good quality of enlargements and the ultimate perspective control ability, albeit at the cost of portability and hand-holdability; medium format is a sort of a compromise between the other two formats that offers better image quality than 35mm but faster operation than with the large format. Very importantly, different formats also impose a different style of and approach towards the photographic process itself and many photographers usually find themselves in different frames of mind when they use different format cameras - obviously, the larger the format, the more contemplative, methodic, and time-consuming your approach shall be.
What is the 35mm format about?
The 35mm format is about one of the following three aspects: convenience, speed, and specialty lenses (including extreme telephoto and zoom lenses). Convenience stands as a separate category, while speed and presence of ultra telephoto and zoom lenses might often overlap.
1. Convenience combined with relatively good image quality is what the 35mm format began with. This is when one wants to take a camera when visiting relatives or to a friend's party and use it freely and casually. This is when you go away on a business trip and do not really have much space to pack a camera, several lenses (either zoom or prime), and a dedicated flash (nor will you have the time to actually thoughtfully assemble and re-assemble your system). This is when you go out for a casual walk with your friend and do not want to frustrate him (or, preferably, her) by constantly fiddling with your equipment. In other words, convenience is about having a ready-to-use and producing relatively-good-image-quality system without carrying a photo bag with you - if you carry a dedicated photo bag, you can as well pack any other system into it. Convenience is about carrying a camera that does not bug you yet gives you a chance to avoid situations when you regretfully think that you should have brought a camera and miss a potentially good shot. All this implies that in this category one should have a relatively small 135 camera with a built-in flash and only one, probably zoom, lens. If we further get down to particularities, you should not be looking at anything bigger than a Nikon F80 - whereas the Nikon F5, Nikon F100, as well as all the professional digital cameras of similar size and capabilities are strictly about extreme speeds and durability required by the conditions and purposes of professional usage. As to the lenses, one would need to balance between size and related to it speed (i.e. maximum aperture), focal length range and quality - but let me leave this up to your personal preferences.
2. Extreme speeds mean the maximum speed of operation attainable - the speed of auto-focus, the speed of frame advance in continuous shooting, fastest shutter speeds, as well as other aspects related to these criterions. Obviously, these features are designed and advanced for action - and for pretty fast action at that, as, say, the Nikon F80 can handle relatively fast action, too. They are for those in photojournalism as they can not afford missing an important moment, for those shooting action, or those shooting wildlife.
The cameras we are talking about in this department are those bigger (and, of course, faster) than the Nikon F80, i.e. F5, F100 and their digital counterparts. They can shoot up to eight frames per second, their fastest shutter speed is 1/8000 or even 1/16000 seconds, and they can keep in focus pretty much anything no matter how fast or in what direction it is moving. Speed is what matters here.
Once again, these cameras are only about speed and durability - they are neither about convenience (which smaller 35mm cameras are about), nor about image quality (which any bigger format cameras are about). Even though they belong to the 35mm format, they should stand as a separate category as they are actually inconvenient - combined with pro-level zooms, they are as bulky and heavy as medium format cameras and cost about the same, or even more, too.
3. Extreme telephoto lenses and zoom lenses. Extreme telephoto is anything that goes beyond 300mm (in 35mm equivalent) - you can not get lenses of longer focal lengths in other formats. In the 645 format, the longest you normally get is 500mm, which is equivalent to 310mm in the 35mm format.
As far as zoom lenses go, they should be about convenience and that is the beauty of them - as long as you consider the so-called "prosumer" zoom lenses, which, with their size and weight, actually do serve the purpose. As to the professional level zoom lenses, they are, ironically, are not about convenience - they are about speed (in terms of maximum aperture and auto-focus) and durability! Their size, weight and price are all very, very inconvenient. They normally go together with the bigger pro-level 35mm cameras.
What's new in the 645 format?
As I have already written above, the 645 format is a sort of a compromise between small and large formats which attempts to incorporate the best features of the two worlds. Although at what size the difference in print quality between 35mm and 645 formats becomes significant is a very subjective criterion (some people say that they can see the difference even in 4X6 prints, while others claim that there is no difference whatsoever in prints as large as 11X14), physics dictate that under equal conditions 645 format inevitably produces better image quality (higher resolution, lower grain and smoother tonal gradation). While certainly more convenient than the large format, 645 cameras are bulkier and slower in operation than 35mm cameras, which requires a more thoughtful approach towards making photographs (some consider this as an advantage, some as a drawback) and defines the appropriate fields of application (e.g. landscape or portraiture photography). Recent technological innovations, however, have made the gap in easiness of operation between 35mm and 645 cameras much narrower - three latest medium format cameras produced by Hasselblad (Hasselblad H1), Contax (Contax 645), and Mamiya (Mamiya 645AFD) offer all the technological advantages that the 135 auto-focus cameras have had for years (especially auto-focus and sophisticated matrix and spot metering), which, inevitably, broadens the scope of applicability of the medium format. Granted, medium format cameras are still noticeably slower in operation than top-end 35mm cameras, yet they are much more convenient than before. Another very important feature of the cameras mentioned above is that all of them are cross-platform cameras, i.e. they can accept both film and digital backs. In the light of the fast development of digital technologies this is a very significant advantage as it makes the camera fairly independent of the recording media it is coupled with thus prolonging its lifecycle. At the same time, it does not pose the film vs. digital dilemma so severely as one can use both types of media at the same time.
General conclusions
Considering the recent developments in 35mm and 645 formats, as well as the features outlined above, the following seems to be a relatively rational approach:
1. Use the "light" part of the 35mm format if you need compactness and convenience. This most likely means one small camera (not bigger than the F80 (or its equivalents from other brands) - and the Nikon F80 is the best of them among film cameras) with a built-in flash and one zoom lens (or, maybe, one to three prime lenses depending on your style and personal preferences). Another alternative would be a digital camera of similar size and capabilities (here, however, you will need to have a further look into the image quality and price issues and decide what suits your needs best). Nikon F100 and bigger cameras, film or digital, as well as any pro-level zooms with constant maximum aperture (usually f/2.8) are excluded from this category.
2. Stay in the "heavy" part of the 35mm format if you need extreme speeds of operation in terms of both cameras and zoom lenses or extreme telephoto lenses or both at the same time, i.e. if you shoot action or wildlife. Photography is not a cheap hobby to begin with, but this is the category where you are really going to feel it, especially if you want to keep up with all the technological innovations. I should emphasize again that a more-or-less well rounded pro-level 35mm kit weighs and costs about as much as a 645 kit.
3. Buy into a recent AF 645 system if, given the same weight and price, significantly better image quality is of more importance to you than the extreme speeds, wide-range zooms, or telephoto lenses longer than 300mm (in 35mm equivalent). As things are now, here you get almost as much convenience as in option two but at slower speeds (which, of course, is compensated by a far superior image quality). This also seems to be the best option if you want your investment in photographic equipment to last for a relatively long time period.
It is very important to note that the above three categories are not mutually exclusive but rather supplementary. In theory, one can buy into all three classes if one's scope of photographic interest is very wide. In practice, however, this would require a very significant investment and most of us would have to make compromises here.
My personal preferences
Recent changes and the challenges of the 35mm format described in the Preamble now have me, quite frankly, facing the issue of whether to stay in the 35mm format at all and, if so, in what form (film or digital), to what extent and for what purposes. Having clarified what 35mm and 645 formats are about, the only thing that I need to do now is juxtapose it with the types of photography that I do to see overlapping areas and draw conclusions.
If I have to define what types of photography I do, though without restricting myself, I would say mostly landscape and cityscape, portraiture and people, as well as social events. Apart from this, due to my current lifestyle and the kind of work I do for a living, I travel quite often and like always having a camera with me. I do not do sports, action or wildlife photography and due to this do not need extreme speeds or telephoto lenses. To suit these needs, I would need a small camera for trips and a kit for the times when I set out to specifically take photographs. For this, the following seems to best suit my needs:
1. A small 35mm camera for casual use. In my opinion, the Nikon F80 is probably the best choice here as I want to buy into the 135 format as little as possible. I do remember that film in 35mm format is dying; however, the Nikon F80 now costs only USD340 and I think that it offers the best image quality and combination of features one can get for this money. I do not want to invest into a half-serious digital SLR as yet as I think that they still have some way to go to achieve high enough quality at low enough prices.
2. I shall keep my Nikon F100 for shooting social events. I at first thought that a Nikon F80 should be enough for this; however, on one occasion I used both F100 and F80 side-by-side and discovered that F80 is just not good enough for events - its auto-focus is not fast enough, has much more hunting in relatively dark ambient light conditions, and its shutter lag is too long. Another reason for keeping the F100 is just that it is too fine a piece of machinery to sell!
3. For the rest of photography I do an AF medium format kit would suit my needs best - it would offer enough speed and convenience together with a significantly better image quality as well as independence from the recording media, i.e. would be a longer-lasting investment.