Tuesday, April 24, 2012


Digiscoping (taking photographs or video through a telescope) can be a frustrating part of birdwatching and seem like a bit of a dark art, but it can be made a lot easier with the right equipment, techniques and some practice. The appeal is obvious; using a telescope both for viewing and as a long-focus lens, often with a relatively cheap camera getting respectable results and offering magnifications beyond the capabilities of even the most expensive SLR camera lenses. The possibilities of this photographic form can be seen in the entries for Swarovski's digiscoper of the year.  With advances in camera technology and better adapters on the market digiscoping has become very popular.
Hoopoe digiscoped.

The equipment required is a short list:

A telescope.

A device capable of recording an image.

A means of attaching this device to the scope.

Any scope will do to an extent. The easiest to use are those with a larger diameter eyepiece lens. These days this really only excludes some of the older second hand scopes with early zooms. Also the larger the objective lens the better, because this gives a brighter image allowing faster shutter speeds.

The camera is a bit more critical, and there are a few options for how you can digiscope. The most popular way is to use a small compact digital camera held up to the eyepiece. This method is often the most convenient and is the least disruptive to using the scope for its intended purpose of viewing wildlife. For this a small compact camera with an optical zoom range of no more than 3-4x is ideal. Any greater zoom often means you can't get rid of vignetting (dark corners to the image or a circular image), and sometimes makes it hard to get sharp results. It may seem counter intuitive, but it is often the cheaper, lower-specified cameras that give the best results. Top-of-the-range compact cameras such as the Leica X1, Canon G1X or Fujifilm X10 may be outstanding photographically, but their large sensors and wide maximum apertures impair their digiscoping performance.

The alternative to a compact is an interchangeable lens camera (digital SLR (DSLR) or a mirrorless system such as micro four-thirds). These cameras can be used in a similar way to compacts in that you can have a lens attached and take photographs through the eyepiece, but on some manufacturer's scopes adapters are available that go in the place of the eyepiece.

Hand-held digiscoping often produces
 results like this.
You can get passable results hand-holding a compact camera or an DSLR with a lens up to the scope eyepiece but the results can be very hit-and-miss and often look something like the photo on the right. for sharp and steady shots it is best to have a rigid connection that holds the camera in perfect alignment. The adapter required depends on the scope and camera you have. Some manufacturers have their own adapters specifically designed for their scopes, and these tend to work the best, but there are also universal adapters that enable photography using a wide variety of older scopes and models that don't have their own adapters.
Opticron's compact digital camera kit
which includes the Panasonic FS45
One of the neatest digiscoping kits available is offered by Opticron. In the box you get a Panasonic camera (a good pocket-sized camera in its own right) and a compact mounting bracket and tube custom-made for the camera. This fits onto Opticron's HDF zoom and fixed magnification eyepieces and an alternative tube is available for the new SDL zoom. For a quick and easy adapter for Opticron scopes (and some others makes with similar diameter eyepieces) this takes some beating. Opticron also have an adapter for DSLRs.

Swarovski produce what is probably the best engineered range of adapters, each designed to suit different cameras and requirements.  Both of the adapter are available for the ATX/STX and ATS/STS scopes.  For those wishing to use a compact camera and switch rapidly between viewing and taking photos there is the DCB II swing-over bracket which keeps the camera held over the scope body when viewing and allows it to click perfectly into place when you want to take a picture. 
Below is a video demonstrating the DCB II on the ATX range of scopes.

If you are going to be mostly taking photos and want the best image quality and advantages of a DSLR's low-light performance, manual control and better sound recording with video then the TLS APO adapter is best.  Below is a video demonstrating the TLS APO on the ATS/STS scopes.

Photo by Eddie Myers on an iPhone 4

Mobile phone digiscoping
Many mobile phones now have reasonably good cameras capable of recording high-resolution stills and video and they can be used for “phonescoping”.  The quality of cameras built into mobile and smart phones has reached a point where they have the performance of many pocket sized compact cameras. This has revived interest in digiscoping with phone cameras and the appeal is clear, having one lightweight piece of equipment that performs the roles of communication and photography. Add to this the possibilities offered by smart phones of uploading photos to the internet and emailing them out in the field and even live streaming video and there is great potential for this type of photography. Just like digiscoping with a conventional camera the results are greatly improved with an adapter that can hold the phone securely in the correct alignment.   Kowa and Meopta make bespoke adapters for Apple iPhones and Viking make a very capable light weight universal phone adapter.  A feature of the iPhone that makes it especially suitable for digiscoping is the ability to use the volume control on the headphone wire as a remote shutter release.

Why do digiscoping
Sparrowhawk outside our
Glandford shop
Digiscoping will never deliver the image quality that can be achieved with a DSLR and a dedicated long telephoto lens, but it does have some significant advantages. For starters there is the weight and bulk of the equipment you are carrying. A DSLR and a 400mm + lens is not small and light by any means, and realistically you have to make a choice between taking a scope or a camera and long lens. If you are out birdwatching with binoculars and scope, the additional equipment required to digiscope is quite light and compact. Then there is the magnification. Even an 800mm lens, the longest available for many cameras, gives a magnification equivalent to about 16x on a typical APS-C sized sensor DSLR. Digiscoping however can deliver a lot more. Most zoom eyepieces on scopes start at 20x and this is multiplied by the magnification provided by the camera. My own compact camera works best on a scope when zoomed in to 110mm, or about 1.5x magnification (75mm = 1x), this gives a total magnification of 30x, the same as a 1500mm lens on a DSLR (taking into account the 1.5x crop factor of most DSLRs). I apologise if this seems like a load of jargon-filled gobbledygook, but this is hard to avoid when talking photography. In simple terms a cheap compact camera attached to a telescope can give you magnifications beyond the reach of the best telephoto lenses. And finally there is the cost. A digiscoping set-up can range in price from around £160 for the scope and adapter plus about £100 or so for a camera, to a top-of-the-range scope with a digiscoping adapter and camera for around £2500. Compare that to a DSLR and 500mm or 800mm lens and you will be looking at a price range more like £1500-£15000.

In addition to stills photography most digital cameras and smart phones can now record video, many in high-definition, which can be an excellent way of recording the behaviour of birds and mammals. Another advantage of video is that it is often possible to get good results in poorer light conditions than with stills. For some examples of the kind of results that can be achieved see video of a lesser redpoll above and our Flickr page.  These videos were recorded in full HD, but have had to be scaled down for the internet.
River warbler digiscoped in very
 early mornin light

For me the best part of digiscoping is the ability it gives you to get a record of birds you have seen and as an aid to identification after the fact. Many birdwatchers have encountered unusual gulls in odd stages of moult or mystery waders that manage to look like at least three different species at once, and in these situations having a photo or a short video can assist with a positive identification or lend weight to your claim of a slender-billed curlew on your local patch.

Digiscoping is not restricted to telescopes, it is possible to get photos through binoculars and microscopes aswell.

The stamen and pollen of a common
field speedwell flower. The total area
 of this uncropped picture is less than
2mm across
Compact attached to a microscope.

A few hints and tips.
When putting a camera up to the eyepiece of a scope it is sometimes tempting to get it as close to the eye lens as possible, but it is often better to have it a few mm to a cm away. You wouldn't press your eyeball onto the eyepiece.

Select the shooting mode on your camera that prioritises the widest aperture and fastest shutter speed (e.g. aperture priority (Av) or “Sports” etc.)

If your camera has an auto-focus assist lamp turn it off because when digiscoping it will be pointing at either the back of the scope or the ground, not what you want it to focus on.

For the same reasons turn the flash off.

And finally, do not despair. Digiscoping takes a bit of practice and a lot of patience, but can be a great enhancement to the enjoyment of birdwatching.

Focal length and magnification explained.
The magnification of nature watching telescopes and binoculars is expressed as how many times closer the object you are looking at appears (e.g. 8x). With camera lenses the magnifying power is expressed as a focal length in mm (e.g. 500mm). Before the days of digital cameras the size of the area that an image was recorded on depended on the type of film the camera used. The most popular size used in SLR cameras and point-and-shoot compact cameras was 35mm (actual dimensions 36mm x 24mm) and this is still used as a reference for digital cameras. The most common size of sensor in digital SLR cameras is known as APS-C size, which has an area smaller than that of 35mm film. This is know as the crop factor of the sensor because it has the affect of cropping the image projected by the lens and so magnifying it. APS-C sensors magnify the image by 1.5x compared to 35mm film, so a 500mm lens on a DSLR is the equivalent of a 750mm lens on a 35mm film SLR. Compact digital cameras have even smaller sensors, but still often give the focal length range in terms of 35mm film equivalent. One common misconception is that a compact camera with a 4x zoom offers 4x magnification, but in this case the 4x referrers to the zoom range, which is 4x the shortest focal length. As an example my digital compact has a 4x zoom, with the shortest focal length being 28mm and the longest being 112mm, or 28 multiplied by 4. 112mm is in fact 1.49x magnification, because a focal length of 75mm is approximately 1x magnification.

No comments:

Post a Comment