Digiscoping

Disigscoping is a method of obtaining photographs using a digital camera through a spotting scope to create powerful telephoto pictures. It is a modern from of telescope photography which is normally associated with astronomers. Historically the 35mm SLR or large format cameras were used, but with the introduction of digital cameras it has become of interest to wildlife photographers. It is also a technique popular with birdwatchers who have found the digital camera a useful addition to their field telescopes. The technique amongst birders is sometimes called digiscopy birding. For this variety of digiscoping, fast shutter speeds and minimal shutter delay, and good lighting are more essential due to the fact the subject is usually moving, if only minimally.

To be able to Digiscope you use a telescope/fieldscope/spotting scope instead of the camera lens for extreme telephoto photography.

There are a number of approaches that can be used, these include:-

A scope and a special camera adaptor for a DSLR that replaces the eyepiece
A scope, eye piece, a connector bracket and smaller digital camera
A scope, eye piece and some sort of bracket or alignment device that allows the camera to be lined up to see through the eyepiece.

In addition in each case you need a tripod, and will need an editing package to allow the resulting photographs to be improved. The editing software is needed to improve on the images you have taken, some may be under exposed and soft, and will most likely suffer from vigneting, the dropping off of the images towards the outside and possibly the cropping off of the corners.

Nikon have a Digiscoping System Diagram which shows how their systems go together. The camera can be a DSLR/SLR or either a point and shoot type like a Nikon Coolpix, or a mobile phone camera or similar camera. The adapter allows the camera to be connected to the eyepiece of the field scope.

We have explored in another article (click here to read) the first of the above options, where we are looking at a Nikon DSLR and adaptor being used and compared the results with options to use longer telephoto lenses.

If we now consider the options beyond the replacement of the eyepiece by a special adaptor as in the case of our DSLR article we discover that for the best results, it is crucial that the optical axis of the camera and the fieldscope are in alignment. The distance between the camera and the fieldscope eyepiece is also important there are now adapters available to do this. Some people however manage to configure something to do this ranging from complex brackets to pieces of tubing. The quality of the fieldscope and eyepiece are also critical factors. The camera and scope also have to be kept quite still, any vibration will cause the resulting images to be blurred, hence the need for a good tripod. Focusing is done on the scope, usually the camera will need to be operated in 'manual' mode. The high magnification to aperture ratios give slower shutter speeds compared with conventional telephoto lenses, so an ISO of 400+ will be needed on digital cameras. It may also be wise to use a cable release or remote control to reduce camera shake when operating the shutter.

There are some factors to consider which can have an impact on the quality of the picture and these include pushing the optical zoom on a point and shoot camera to too great a distance, or using digital zooms, camera/scope movement and atmospheric disturbance like heat haze, and dust which can reduce contrast and introduce blue into the image. Another problem is depth of field, working with such long focal lengths and a fixed aperture will result in limited depth of field, so slightly miss your target and they will be out of focus. The conditions of the day are also important, good light is needed

It is also difficult to track your target down over such distances. You may just be able to see the object with your eyes, but with the magnification of the scope getting it to line up with what you see can be a challenge, and if not quick enough your subject may have gone. Even getting a tripod to lock in a position where it is lined up with your target can be a challenge. The system will also be poorly balanced as the tripod mount on the scope was set to balance with an eyepiece and not a camera and other items added the extreme end. Some scopes may also not be strong enough to survive the stresses involved. Again some brackets have been developed in an attempt to overcome this problem.

How close you can get, or how long the lens is, will depend upon the arrangement used:-

With a DSLR and special adaptor instead of an eyepiece you have 800mm or 1000mm, the equivalent to 1,200 or 1,500 mm on a 35mm camera. This is with a working aperture of F13. You could put in a teleconverter (non Nikon) and double this length to the equivalent of 2,400 or 3,000mm but at the cost of three stops of light.

By selecting different Coolpix cameras and by changing eyepieces and scope you can get a magnification ranging from 1,700mm to 9,300mm, with a corresponding range of apertures. The longer you make the system generally the lower the light you have and the harder it would be to set up and get good results from.

With point and shoot cameras and phone cameras, if you can line them up you should be able to get similar high magnifications, however getting and keeping alignment and focus has to be overcome, although there are some brackets made that claim to assist with this. It is difficult to get any reliable information that will allow these systems to be compared with the above.

Digiscoping is not widely practiced by general photographers, more by people who already have scopes, and a specific interest, most often birding. If you already have a scope and a camera then trying the two together is not a major cost compared to building an experimental system to try this out. Digiscoping is also not for the fainthearted if you decide to experiment with this, expect to have problems to overcome, but it does offer the potential at least to get closer to nature, perhaps on a more limited budget, particularly if you already have a suitable scope.

It should also be remembered that solutions using lenses can be also configured, and in particular combinations with mirror lenses or other lenses and one or more teleconverters. When taking these to extreme lengths they are rather dark and difficult to focus. The longest arrangement we have tried was an older 500mm Tamron lens with a 3x, and two 2x teleconverters connected. The equivalent to a 6,000mm lens. Photographs could be taken, but a lot of editing work would be required to make acceptable images.

It is often not necessary to go to such lengths as frequently a section of an image can be taken, and if the requirement is for low resolution screen images this can be a small section of the image. Therefore a 400mm or 500mm lens, and sectioning may be sufficient to achieve your objectives and produce a more usable image that requires minimal editing.

We have produced another article comparing the DSLR adaptor and digiscope route to the option to use lenses with more information on the digiscoping challenge, click here to read this now.

When looking at the many websites on the internet that show images taken on a digiscope or telling you how to set up such a system, you should remember that:-

Screen images are low resolution 72dpi compared to 300dpi often used for printing therefore the images may be a small section of the image taken and may not print out.
Comparisons of the scene and the area covered may be made to look extreme by taking general shot with a wide angle lens, and if you compared a general shot with a 10.5mm lens to the section contained in a 1000mm lens you have less than 150^th of the image width. If you then sectioned the 1000mm image the area drawn on the wider shot would be too small to show. These images can therefore be misleading.
You have no idea of how many photos had to be taken to get the images shown. An enthusiast may have taken 20,000 photos and be showing 6, so although the 6 may look good you may not be prepared to take enough to get the same results.
Some who are pushing the digiscoping topic so strongly are promoting the sale of scopes, brackets and systems.

Some other websites you may like to look at for more information are:-

http://nikon.topica.ne.jp/bi_e/products/nature_c.htm Nikon Sport Optics Nature Watching section where it gives information on the products and adapters they have to connect their camera ranges either Coolpix or DSLR's to their Fieldscopes.

http://www.digiscopediary.co.uk/ This website put together by a keen digiscoper provides information on digiscoping equipment, techniques, product tests, hints and tips as well as pictures.

http://digiscoper.org/blog/ another site showing pictures of what can be achieved with this method of photography. The images are quite good in that it shows the wide view/position of the photographer in different locations around Scotland followed by the photographs taken at the time using the digiscoping method.

http://www.digiscoping.co.uk/ A resource put together by London Camera Exchange (LCE).

http://www.birddigiscoping.com/ an American website where you can see lots of close up photographs of birds using the digiscoping method.

If you have any experience, or decide to try any digiscoping let us know how you get on.