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Message: <blockquote data-quote="Can Popper" data-source="post: 609706" data-attributes="member: 39163">40mm PlosslI went out to the gun ranges again to try out my universal digiscoping adapter.  The eyepiece I used on it was the 40mm Plossl and the Pentax SMC zoom (24mm to 8mm version).The 40mm Plossl, as usual, took wonderful pictures.  I think it is the most goof proof digiscoping eyepiece around.  I also took pictures through my SMC zoom.  The zoom provides good images and great color but it has a big drawback.  When I change the magnification on the zoom, the eyerelief changes and I need to readjust the position of my camera on the digiscoping adapter.  A great annoyance.  Zoom my Fuji F10, however, does not require a readjustment of the camera's position.Below I am posting three pictures.  One is of the targets shot through the SMC zoom at 24mm.  The second is of the targets through the 40mm plossl with no camera zoom.  The third is of the targets through the 40mm plossl with 3x camera zoom.The photos turn out to be quite revealing.  If you compare the two no camera zoom photos of the SMC at 24mm and the 40mm plossl, you will see apparent field of views appear to be identical.  However, the 40mm plossl has a much larger true field of view, just look at the great area you can see with the plossl. Now in the third picture, I camera zoomed to the max of 3x.  Notice how the magnification is now close to double (47x) that of the Pentax at 24mm (26x) but the true field of view or the area is the same (look at the edges along the wooden rail).  Thus the 40mm plossl allows you to see more and find objects more easily.  While I was downloading the pictures from my camera to computer, the thought occurred to me that the 40mm plossl may be able too allow the user to digiscope birds in flight.  Its wide true field allows the digiscoper to find and track the birds more easily.  Its largest exit pupil (about 6.25mm on the 100ED and 6.67mm on the 65ED) would facilitate very high shutter speeds.  Finally, the great depth of field would allow the picture of the bird in flight to be more easily taken in 3D space.   The pictures should be take with no camera zoom in order not to reduce the true field of view.  Just make sure the camera is set to the highest resolution so that there will still be alot of pixels to cut out of the unvignetted area.</blockquote>

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