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Message: <blockquote data-quote="Paul Corfield" data-source="post: 1850837" data-attributes="member: 19132">I remember when Yvan did that Powermate test but unfortunately I think he returned it before we could get to the root of the problem.Powermates in the 2X and 2.5X varieties produce a very parallel light path so you gain very little in magnification by moving it further from the camera. Actually the 2.5X version produces less magnification by moving it further away. There's a good diagram on this link showing how distance affects the Powermate magnification. They also do a Powermate T-ring adapter which makes for a compact set up. There's a photo on this link. <a href="http://www.televue.com/engine/page.asp?id=42" target="_blank">http://www.televue.com/engine/page.asp?id=42 </a>Pretty sure that with moving barlows further from the camera you are just getting a cropping effect, just like putting a full frame lens on a small sensor dslr. Moving the barlow produces a bigger image circle which falls well outside the size of the sensor. I'll do the test later today.Paul.</blockquote>