<a href="https://www.flickr.com/photos/34688260@N02/13905327267" title="untitled-3-1 by saltytri, on Flickr">"800" height="598" alt="untitled-3-1"></a> Since I use the three DP Merrills mostly on a tripod with an RRS clamp, I wanted a convenient way to switch from camera to camera while using the same HoodLoupe. Three imported base plates were fitted to the bodies and a fourth was fitted to the HoodLoupe. It's important that they all be the same width so that the clamp engages the camera plate equally with the HoodLoupe plate. If the plates aren't the same width, one will remain loose when the clamp is tightened. I found that the width of these plates varies a little from source to source so all were purchased from the same supplier at the same time. <a href="https://www.flickr.com/photos/34688260@N02/14088726361" title="untitled-4-1 by saltytri, on Flickr">"800" height="533" alt="untitled-4-1"></a> A piece of plastic was shaped as a spacer between the HoodLoupe and the base plate. It needs to be thicker at the aft end to compensate for the shape of the HoodLoupe. It is cut with a slightly greater angle so that the HoodLoupe tilts forward just a bit at the top. This forces a tight fit between the camera and the rim of the HoodLoupe when the two are slid together in the clamp. Thus, light is sealed out, particularly along the top edge. <a href="https://www.flickr.com/photos/34688260@N02/14112015683" title="untitled-6-1 by saltytri, on Flickr">"800" height="554" alt="untitled-6-1"></a> The base plate and plastic spacer are attached to the HoodLoupe with a single #6 machine screw that goes through all three pieces. There is no slippage because the spacer contacts rubber pads on the top of the base plate and seats firmly against the rubber housing of the HoodLoupe. The rubber housing is supported by an inner structure of ABS plastic, so the HoodLoupe is stiff enough to make this work. Even so, a large fender washer was used against the ABS to make sure that the clamping pressure of the machine screw was well distributed. Both the washer and the screw head were "painted" with a black Sharpie so that they aren't obvious when seen through the eyepiece.