Stephen Ingraham (who?)
the unofficial site for birders and digiscopers using Zeiss equipment.
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Digiscoping with the Zeiss Diascopes and the Digital Camera Adaptor Setting up your DCA to fit your camera. We recommend that you read these pages through to the end, and study the illustrations, before you begin to try to use the DCA for the first time. Once you understand the basic principles better, following the instructions will be lot easier. If you are quick study, the illustrations and captions provide enough information to get your DCA up and running without reading this text. If you already own a camera, and have already figured out how to mount it on the DCA, you may want to proceed directly to Field Technique. The Zeiss DCA is a unique tool. It does indeed allow use of the spotting scope for visual observation, and all but instant conversion to image capture mode. You just swing the bracket out for observation, and then swing it back in for image capture. However, like any mechanical device, it takes some adjusting to work correctly with your individual camera, and it requires that you develop some specialized techniques to get the most out of it. We will cover basic set up first, and then talk about more advanced techniques. The DCA will fit the vast majority of digital cameras on the market today. No front filter threads are required. All you need is a tripod socket. It will take cameras from the smallest pocket wonders, to full DSLRs, the size of regular 35mm equipment. The Goal is to center the camera lens exactly behind the eyepiece of the scope, both vertically and horizontally, and to place it the correct distance from the eyepiece so that you get a full field of view using as much of the zoom range of the camera lens as is possible. Most cameras, as above, with a maximum 1-3 zoom, can be adjusted to give you a full field for the upper half of their zoom range, and some can be adjusted to give you a full frame at all zoom settings. You can see from the illustrations that the DCA has three axis of adjustment. There is a vertical slider which holds the camera platform. The slot in the camera platform allows side to side, horizontal movement of the tripod screw, and therefore the camera. It also provides adjustment to make sure the two lenses are parallel to each other. Finally the slider between the tripod plate and the camera platform provides movement to adjust the distance between the camera and the eyepiece. Notice that there are two set screws on the distance slider, one on the bottom and one on the top. The bottom set screw loosens the whole slider so distance can be adjusted. The set screw on the top can be set, once the correct distance is determined, as a “quick stop” so that the distance slider can be returned to the correct setting quickly if it has to be slid out to move the camera from behind the eyepiece. Some Assembly Required: That flexibility and range of adjustment, however, means that “some assembly is required” for most cameras. In my experience, most of the smaller digital cameras require that you “disassemble” the DCA as it comes out of the box, and reassemble it to fit your camera. There is some mention of this several pages into the instruction manual, when talking about 35mm SLR style cameras, but the fact is, you will have to do it for many compacts as well. The problem is that “out of the box” the DCA has “almost” enough vertical travel to center the camera lens behind the eyepiece, but not quite enough. It is close enough so that you might be tempted to just leave it. Don’t do it. I will walk you through the process of disassembling the DCA and putting it back together so that it will have ample range to center your lens exactly. Centering will make a wonderful difference in the quality of the images you can capture. It is not hard. Follow these illustrations and instructions.
1) Remove the distance slider arm. The set screw on the distance slider arm is a “captive” screw. It only backs out so far and remains attached to the arm assembly. Clearly this is necessary, to avoid dropping it all the time while adjusting the DCA. If you look at it closely you will see that it has a “retainer screw” on the up side of the arm, opposite the knob. Place an appropriate screwdriver in the screw slot in the retainer screw. While holding the retainer screw steady, twist the knob past its normal stop to break the retainer screw loose. Remove the screw with the screwdriver.
You have now separated the DCA into two parts: the main mount and the distance slider and camera platform.
2) Now, remove the set screw that holds the camera platform on, turn the distance slider up-side down, and reinstall it so that the short arm of the L is pointing down. (I also turn the platform around so that it extends behind the vertical arm. This gives you easier access to the tripod screw, and a bit more reach on the distance adjustment.)
3) Remove the “quick-stop screw” from the distance slider. (Careful, there is a little black disk that rides in the slot at the other end of this screw from the knob. (Don't drop it. Don’t loose it.) Reinstall the quick stop so that the knob is pointing up again
4. Finally, reinstall the distance slider and camera platform by putting the set screw up through the slot in the arm and screwing it into its hole in the main mount. Replace the retainer screw and tighten it down firmly.
In this configuration, the DCA will allow the majority of digital cameras to be centered behind the eyepiece, but you should now understand the principle of how the adaptor goes together, and be able to arrange the different parts in some configuration to fit almost any digital camera.
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