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Message: <blockquote data-quote="Paul Corfield" data-source="post: 1674723" data-attributes="member: 19132">Took some photos this morning before it started to snow here. Lovely cold air means you can photograph at long range without any air disturbance like you get in the summer.Regarding extension tubes, I took all photos this morning with a 50mm extension tube in the back of the scope. I've listed the minimum focus distance with this 50mm length of tube.Scope on its own will focus down to 9.5m approx.With any teleconverter focus is 10mWith 2X barlow focus is only around 15m or 16m. The barlow requires at least 75mm extension to get down to 10mHad to compress the photos quite a bit because of all the pine needles so some detail will be lost in the compression.1st photo is with just the scope.2nd photo is with Kenko Pro 300 1.4X TC stacked with the DOI 2X TC stacked with the 2X GSO barlow. I'd guess it's giving about 5X overall as the GSO barlow is only about 1.5X on the camera. So in mm this is around 3500mm equivalent. As this image shows a small bird at this range would be quite easy to capture and in good detail too. The cones on the tree measure around 4".3rd photo is just with the DOI 2X TC4th is with the GSO barlow and I needed about 50mm macro tube between camera and barlow to reach 2X magnification.Coinclusion - teleconverter images have better contrast than the GSO barlow and this includes all barlows, some are much worse than others. Teleconverters require only 50mm extension tube to get good close distance focusing. Detail is pretty similar in both images. Teleconverters can be used with other lenses. So I'd say where possible go for teleconverters first and barlow second. Paul.</blockquote>

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