After years of hesitating between the 35mm and digital formats, I also decided to go fully digital, and since August 2000 all of my photographs have been taken with a Nikon CoolPix 990. The novelty of this approach lies in the fact that by combining the magnifications of the telescope (20x to 60x), the camera (3x optical zoom) and cropping on the computer (0% to 50%), one ends up with a total magnification of approximately 80x, which is equivalent to either looking through a telescope equipped with an 80x eyepiece, or shooting in 35mm with a 4000 mm telephoto lens!
(See illustrative pictures here)

The concept of "digiscoping"...

I coupled my camera and my telescope with a home-made aluminium bracket holding the Coolpix 990 in front of the scope eyepiece. This attachment system remains sufficiently loose to allow easy access to the telescope (in particular with the swiveling body of the Kowa TSN-1) for finding the bird and focusing on it. I currently use a simple plastic ring attached to the camera which fits easily around the telescope's 20X or 30X eyepieces so I can get the camera out of the way at any time to relocate a lost target or retune a soft focus. My intention is to test the Nikon telescomicro 8x20D telephoto lens, mainly for shooting birds in flight (practically impossible with the telescope), but also for shooting at distances of less than 20 feet, when the telescope is useless. This type of photography through a telescope is spreading around the world. In Malaysia, Canada, Australia, Japan, Belgium, USA and the Netherlands, at least a dozen people use approximately the same kind of equipment that I have. Among these, the most experienced, my friend Laurence Poh, from Malaysia, has been using his CoolPix 950 and 990 cameras with his Leica Apo-Televid 77 mm since February 1999; his internet albums contain almost a thousand spectacular photographs. I encourage you to spend hours browsing through these albums; it's much more than exotic birds; it's great art !
An up-to-date listing of active members of the Birds-pix eGroup is available here.

Advantages and disadvantages...

Digital birding photography offers multiple other advantages: 
- many birders already own a spotting scope 
- lightweight camera equipment compared with the 35mm heavy equivalent 
- 80x magnification power, which allows for non-intrusive picture-taking from long distances 
- the chance to visually document rare species 
- the ability to take hundreds of pictures, without any additional cost 
- the possibility of shooting in continuous mode 
- instant results on the camera's LCD can be immediately discarded if not satisfactory 
- display of the pictures on the Internet or by printing in only a few hours. 
- picture processing, with a full range of photographic possibilities, such as sizing, cropping, etc. with appropriate software. I use Adobe Photoshop version 5.5. 

To be fair, one must also list the disadvantages: 
- rather long set-up time (the bird must cooperate and stay put for a few minutes) 
- depth-of-field is always minimal 
- does not work under the lower focusing limit of the telescope 
- limited film sensitivity (100-400 ASA) almost always requires sunlight for quality pictures 
- a writing delay between each shot of 2 to 8 seconds (depending on your CF card) 
- the LCD screen is difficult to view in bright sunlight, necessitating some sort of shading system 
- one has to have a computer to download, manipulate and print files 
- as with all computer technology, equipment bought today will be obsolete tomorrow 
- with current technology (3.3 Megapixels), it is impossible to print quality pictures larger than A4. Prints larger than A4 (two-page presentation in magazine, for instance or a mural enlargement) will remain, but for how long, an exclusive territory of traditional 35 mm. 
- Digital photography also raises the question of the authenticity of the pictures. But of course, it is just as easy today to fake a silver photograph as it is a digital one. It all depends on the integrity of the photographer. 

A list of digital equipment is short and is limited to three essential elements: 

- a digital camera with a 3x zoom, capable of functioning in completely manual mode 
- Compact Flash memory cards (enough  to enable one to take all the needed pictures) 
- two sets of NiMh batteries with a charger 

Of course, one has to already have the telescope, a lightweight tripod and the computer. 

As for my personal choices (Swarovski AT-80 or Kowa TSN-1 / Nikon Coolpix 990), they offer three clear additional advantages: 

- The combination of the 45 degree viewing angle of the telescopes, and the swiveling head of the CoolPix 990 camera makes it possible to shoot upwards or downwards with the telescope and always keep an eye on the tilted LCD screen of the camera. 
- The zoom of the CoolPix moves "inside" the body of the camera, facilitating its coupling to the telescope. 
- There is no mirror movement in the CoolPix. A final argument in favor of the CoolPix 990: In its June edition, the renowned French magazine "Chasseur d'Images" notes that "with its 2048x1536 pixels, the 990 offers a larger pixel surface than its big brother, the Nikon D1 (2012x1324 pixels) and concludes: "In exterior or classic situations, or in macro mode, the 990 produces better images than its big brother, the D1, a conclusion we really did not expect! " Naturally the D1 will always offer advantages with respect to TTL viewing, its unique velocity, superior sensitivity and a chromatic fidelity that's hard to beat, but for approximately ($1000 USD), the CoolPix 990 looks like a nice solution for those who want to get the best of digital photography without bankrupting themselves and remain lightweight." A D1 body alone costs approximately $6000 USD! The storage media is another factor to look into. Currently there are 3 types -Smartmedia as used by Olympus, Compact Flash (Nikon and Canon) and Sony's Memory stick. The highest capacity currently is Compact Flash, up to 196 MB (256 full-sized photos at Normal compression; fewer high quality pictures can be taken for the highest quality pictures). 

Copyright information.

One will notice that my documents on the Internet are compressed at low resolution (Jpeg format, approximately 100 K) and obviously give poor results when printed. I encourage their electronic reproduction without restriction, as long as the photo is accompanied by a suitable mention of the photographer. 
However, the original, high resolution files of these photographs (Photoshop PSD, 250-300 dpi, 1 to 40 Mb), allow for quality printing on inkjet home photo printers in sizes of A5 to A4, depending on the cropping applied on the original picture. For hard copies, or for access to the original files, I should be contacted directly. This access might, of course, be subject to licensing.