You are here:birding >digiscoping >
DeutschEnglishFrancais
2018-07-19 : 7:18 am : +0200

birding

About Digiscoping

Adapter for ATS Ocular (HTY)
Adapter für ATS Okular (HTY)
AT/S Adapter DCA by Swarovski Optik
AT/S Adapter DCA von Swarovski
Colour-ringed Skylark (Digiscoping ATS 80, E990 Nikon)
Feldlerche farbberingt (Digiscoping ATS 80, E990 Nikon)
Digiscoping: Digital camera on a Swarovski Optik DCB digiscoping adaptor (swing-arm)
Digiscoping: Digikamera hinter Objektiv des Spektivs (DCB Plattform Swarovski Optik)
True vignetting - Great Crested Grebe on nest (Swarovski ATS 65, Nikon E990)
Echte Vignettierung, Haubentaucher am Nest Digiscoping ATS 65, E990 Nikon)
The Digiscoping Effect - Rhein Delta. Yellow-legged Gull without digiscoping
Digiscoping Effekt Rheindelta linker Damm: Larus michahellis ohne Digiscoping
The Digiscoping Effect - Rhein Delta. Yellow-legged Gull with digiscoping (Swaro ATS 65, Nikon E990)
Digiscoping Effekt Rheindelta linker Damm: Larus michahellis mit Digiscoping (ATS 65, E990 Nikon)

Digiscoping – digital photography through a telescope

Digiscoping is the general term used to describe photography through a telescope; with its little sibling being digibinning (through binoculars). Fixing a digital camera or video recorder to the ocular lens of the telescope is usually achieved with the help of an adapter – either home-made or specially produced. The good-ol’-fashioned way would be to just hold the camera up to the eye-piece of the telescope or binocular, but this is a rather challenging undertaking even for the steadiest of hands.

I currently use the manufacturer-designed Swarovski DCA – a two ring system where the first ring clamps to my zoom eye-piece, and the second ring attaches directly to my little Canon point and shoot camera (A590IS). This system allows me to easily attach and remove my camera at will, allowing me to store my camera in my pocket while I am looking for birds, and then quickly attach it to the telescope when I want to take a photo or video.

Martin Riesing’s solution is a home-made PVC pipe adaptor that screws on to the front of his point and shoot digital camera (Canon A570/A590). When he wants to take photos, he simply slides the adaptor ring over the eyepiece, giving him a snug and stable fit – a perfect home-grown solution!

When taking photos through our binoculars (we both currently use a Swaro EL either 8,5 or 10x42), we simple hold our cameras up to the binocular eye-piece. Through dumb luck, the zoom lens of our cameras fits snugly in to the twist-up eye-cups of the Swaro EL series, making it very simple to take digibinning photos without an adaptor. Having said that, I tend to keep a Swarovski snap-shot adaptor with me as it adds a whole lot of stability to my diginocked images – with some great results. I find diginocking particularly useful when I am on long hikes and have decided to not lug my telescope back in to the mountians with me.

Nach oben

Digiscoping equipment

To state the obvious, in order to digiscope, you will need two main pieces of equipment:

1.    A telescope
2.    A digital camera

The telescope

The choice of a telescope is of critical importance. It is possible to take a photo through any telescope, but the better the telescope, the better your digiscoping results are bound to be. Of greatest importance include:

  • The amount of light the telescope gathers and transmits through to the camera objective
  • How true the colours transmitted are (warmer/colder tinges, chromatic aberration, etc.)
  • The field of view of the telescope
  • Eye relief
  • The size of the sweet-spot – that portion of the transmitted image that is sharp, bright, and colour-true.


The amount of light that is transmitted through the telescope depends largely on three things: the objective lens diameter (the larger the objective diameter, the more light can be gathered), the quality of the glass used (one top-quality glass lens for a telescope costs as much as €100 before being shaped!), and the coatings used on the glass (the better the coatings, the more light is transmitted).


The colour truthfulness of a telescope depends mainly on the glass, coatings and design of the telescope and even the best of telescopes vary in their ability to deliver colour-perfect images. High definition (Fluoride) glass is more expensive than normal high-grade optical glass, but it is also better able to transmit images with little or no chromatic aberration – the purplish hue that one gets around brightly (back-)lit subjects.


When you try to use a digital camera with a telescope or pair of binoculars, you will more than likely find a black ring around the image. This is called vignetting and is quite normal. The easiest way around it is just to zoom in with your camera a little bit, and the vignetting will disappear (i.e. be out of the frame of the picture). Two factors that contribute to the amount of vignetting you get are the telescope’s Field of View (FOV) and eye-relief. An ocular lens with a wider FOV and greater eye-relief will tend to give much less vignetting. For example, the Swaro fixed 30x eye-piece gives little to no vignetting when I use my Canon A590 with it, whereas my 20-60x zoom eye piece gives distinct vignetting and I always need to use my camera’s zoom to get around it. The problem with this is that then I rely more heavily on the decidedly weaker optical quality of my pocket camera’s lenses (which affects the photo quality). But, the great advantage of this setup is that it does give me a whole lot more zoom range – something that can be wonderful, and even necessary, in many field situations.

The new 25-50x zoom is an absolute dream ocular for digiscoping – combining the versatility of the zoom with enough FOV and eye-relief to give very little or no vignetting on my camera.


The size of the sweet spot is something that is easily overlooked initially. It is the portion of the image that remains as bright, sharp and colour-true as the centre of the image. Many good moderately-priced telescopes have centre performance approaching that of the alpha telescopes when one compares the very centre of the two images. But, the image deteriorates rapidly away from the centre, and any small aberrations in a telescope become very clear on high magnification photographs.

 

The digital camera

Choosing a digital camera for digiscoping is not particularly easy.


A digital single lens reflex camera (dSLR) has the advantage of having a larger sensor (better colours), and able to take faster photos (reaction time and rapid-fire), but such a setup tends to be more bulky and the moving mirror tends to shake the setup more and – unless one has a fancy-shmancy new digital camera with live-view – one is limited to focussing and taking photos using the eye viewfinder. DSLRs are either, fitted directly to the telescope with something like the Swarovski TLS800 – which replaces the regular ocular lens, and creates a 800mm equivalent telephoto lens – or attached via the lens filter thread to an adapter like the Swaro DCA ring adapter (see above). The former system offers the photographer a stable telephoto lens setup, while the latter offers the naturalist the ability to quickly switch between photography and telescope viewing. When choosing the DCA system, it is always best to use the thinnest/shortest camera lens possible in order to keep the weight of the camera body as close to the telescope as possible. Nice DSLRs abound, but one that I have enjoyed is the Nikon D300 (and its predecessors).


Little pocket point-and-shoot digital cameras have the advantage of being small and easy to use, but it is just a little bit harder to take great photos with such a small sensor. This is a compromise most birders (who also like to take photos) are willing to make. Plus, with a little bit of practise, and some helpful techniques, one can still take great photos with many a point-and-shoot.

Arguably the most fun way to attach your point and shoot to your telescope is to craft something yourself with things you can pick up at the local hardware store or lying around at home. Commercially available adaptors include the DCA that attaches via a screw thread either directly to your camera or via an adapter ring produced by the camera manufacturer. Another option is something like the Swarovski DCB – an arm/bracket onto which the camera is screwed via the tripod screw, and which allows the digital camera to be flipped in to and out of position, thus allowing you to quickly switch between photography and viewing.


Some basic features to look for when choosing a compact digital camera include:

  • Zoom – essential to remove vignetting. No more than 5x
  • Clarity of images – how much noise does the camera produce?
  • Range of aperture and shutter speeds
  • Ability to manually set aperture, shutter speed, focus, etc.
  • Remote (electronic) shutter release is a really nice feature but only if the camera responds quickly to activation
  • Rotating display screen is a very handy (but not crucial) feature
  • Number of megapixels. I put this at the end of the list because it is not as critical as most believe – a poor quality camera with 10 megapixels will still give you a poor image, just this time with a whole lot more noise. According to some opinions, the usefulness of more pixels tops out at 6MP with the sensor the size of that in most point and shoot cameras.


Two very popular digiscoping cameras at the moment include the Canon A590IS (great value for money at the moment) and the Nikon P5100.


When choosing your digital camera, it is important to either test the camera out yourself with your digiscoping setup or, to get the opinion of someone who uses (or has tested) the camera for digiscoping. The FOV and image rendition of cameras varies greatly from make to make and even between models and so your results and amount of vignetting can vary considerably.

Nach oben


Digiscoping with Clay Taylor Part I - English

Digiscoping with Clay Taylor Part II - English

Nach oben