That is a question that only you can answer, as it depends on your imaging requirements and your budget.  However, here is some information to consider when making a decision.

There are five key factors:

• Shutter delay
• Image quality
• Focal length multiplier effect
• Speed of turn-round
• Cost

There are also other factors, such as the enjoyment you may derive from using one system or the other, being able to control the output, and the time that you have available.

Shutter delay

My limited experience with friends’ digital cameras (“Here.  You take the pictures for me; your pictures always come out so well!”) is one of constant frustration because of the delay between pressing the shutter and the camera deciding to take the picture.  With people shots (or any action shots), the precise moment is crucial.  If the camera fires even one second later, the image is probably not worth having, as gestures and candid expressions can be so fleeting.  Time was when all digital cameras seemed to have a delay of up to 2 or 3 seconds, which is really quite unacceptable.  Many of the newer models are much better, but there is still the delay introduced by autofocus (OK, you can have that problem with film cameras, too, but why use auto-focus lenses?!).  In my opinion, digital hasn’t yet reached the point where you can even be sure of capturing good candids of the children – though you will know quickly that you didn’t get the shot that you wanted!

Image Quality

If you must have ultimate image quality and the ability to make massive enlargements, using film as the originating medium is still the way to go (at the time of writing!)

You may choose (like me) to shoot film, but print digitally.

If you scan in a “6×6” negative (actually 56mm × 56mm) at 4800 dpi, you will get a file that is 10,488 pixels × 10,488 pixels.  This results in a 629.4MB image – about one hundred times the resolution of most current digital SLR files!

• This will produce a high-quality print at 300 pixels per inch that is 88.8 cm × 88.8 cm (34.96 × 34.96 inches)!
• Many people print at 240 pixels per inch.  The image size would then be 1 metre 11 cm × 1 metre 11cm (43.7 × 43.7 inches)!
• In fact, images this size are usually viewed at a certain distance, and you would easily obtain perfectly satisfactory results if you printed at 150 pixels per inch, giving you a print 1 metre 77.6 cm square (nearly six feet by six feet)!

The focal length multiplier effect

Also bear in mind that even Medium Format sensors are not “Full Frame”: instead of a 56mm×56mm image you get something that is at most 48mm×48mm, and with many Medium Format backs substantially less than this.  This has an impact on all the lenses that you use, effectively making them appear to have a longer focal length.  This is especially a problem with wide angle lenses, where a 40mm ultra wide angle may provide coverage on a digital sensor equivalent to a 55 or 60mm lens on a full 56mm×56mm film frame – and in most cases with Medium Format equipment you will not find a wider angle lens available to give you the angle of view that you were expecting.  This is in particular a problem for shots of interiors, but can also be a problem for landscapes and other types of photography.

Speed of turn-round

Digital images give you of course an almost-instant turn-round, though it is not quite as instant as you think.  It does take time to

• transfer the image from the camera to the computer
• convert from raw to another format
• process the image as required (contrast, sharpness, colour balance, etc)
• produce the print

• You need a scanner that will take Medium Format film – although these are no longer difficult to find, nor expensive.
• You need a fast processor and plenty of RAM on your computer.  My computer has a 2GHz processor and 1½Gb of RAM, and it can take nearly an hour for my film scanner to scan a colour frame at 16 bits per colour, with the dust correction tool operating, process it, and deposit it in my image-manipulation software!  A faster processor and 3 or 4 Gb of RAM would dramatically increase the speed of this.

A digital back for a Medium Format camera such as the Hasselblad would currently cost you in the region of US$20,000, and even with this the image quality would be way below what you can achieve by shooting film in a Pentacon Six and then scanning it into your computer.  Using the mixed film/digital route is not a zero cost alternative, but you probably already have a computer and a printer.

A digital camera – even a 35mm one – may give you the quality that you need, but that won't be in the same league as what you can get with film.  And even a 35mm digital SLR with a full-sized sensor will also cost you a lot more than a Pentacon Six.

Pentacon Six and digital!

Of course, going the film route is a lot slower – you have to get the film processed, and then do the scanning in, which is laborious and time-consuming.  Also, you may not need to produce door-sized prints. 

As you can see from the above, my solution at the moment is to use the Pentacon Six and digital.  For best-possible quality, I shoot on a Pentacon Six or Exakta 66 (occasionally a Kiev 60, Kiev 88 or Hasselblad 500C or 500C/M).  I have the film processed in a lab, having given up on doing my own film processing – although now in 2007 I am thinking of starting again, mostly to avoid postal delays.  Unless I am testing a lens I get small 5"×5" prints made, which are cheap and serve as proofs only.  I have given up on sending poorly exposed or badly colour balanced prints back to the lab for re-printing.  It is not worth the hassle, and it’s quicker (even with the scanning times indicated above) to scan it in, re-touch it if necessary to remove dust or digital artefacts, and print it myself so that I get an image that looks the way I remember the original scene.

I have 60cm × 60cm prints on my dining room wall (we feel that larger would be overbearing and out of proportion to the room) and prints in a range of sizes throughout the house.  We occasionally enjoy projecting slides shot with the Pentacon Six / Exakta 66 at anything up to 6 feet wide.  (Digital projection may get there one day, but look at the resolution figures right now – for anything other than a moving image, the quality would be awful at this size.)