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<p>[QUOTE=&quot;benveniste, post: 2663720, member: 25547&quot;]First you claimed that the 105mm VR was &quot;unusable&quot; because you could do lighting setups with a bellows that you can&#039;t with the 105mm VR.&nbsp; And now you are claiming you don&#039;t use such a setup.&nbsp; Gotcha.</p><p><br /></p><p><br /></p><p><br /></p><p>Again, argument by assertion.&nbsp; How much droop are you claiming?</p><p><br /></p><p><br /></p><p><br /></p><p>And yet you didn&#039;t realize your Pentax bellows doesn&#039;t have a movable tripod mount and you won&#039;t post a shot of any of these setups.&nbsp; Gotcha.</p><p><br /></p><p><br /></p><ol> <li>So a 105mm lens becomes a 65 or 70mm lens at 1:1, while an 85mm lens becomes a 55 or 60mm.&nbsp; (Both provably false.)</li> <li>The lens itself is quite large in diameter.&nbsp; (It&#039;s no wider than the bellows plate).<br /> </li> <li>Coupled with the relatively short working distance, this severely limits the lighting angles you can achieve.&nbsp;&nbsp; (It&#039;s 2mm shorter than the theoretical maximum for a 75mm lens, which means in real life it&#039;s longer).<br /> </li> <li>It is a heavy lens, and causes the system to sag.&nbsp;&nbsp; Even with a perfectly rigid mount, the camera itself will sag a bit. (Not demonstrated or quantified.)</li> <li>Droop <i>always</i> occurs and must be compensated for. (Not demonstrated or quantified.)</li> </ol><p><br /></p><p><br /></p><p>I don&#039;t claim to be able to, and you&#039;ve already stated that you won&#039;t &quot;waste your time&quot; demonstrating that you can.&nbsp; But just for fun, let&#039;s do some simple math. Your enlarging lens has a filter diameter of 40.5mm when reversed.&nbsp; To &quot;fill the screen&quot; with a dime requires a 1.34x magnification.&nbsp; To accomplish that with a 75mm lens in turn requires a subject distance of 131mm from the center of the lens.</p><p><br /></p><p>This in turn means that even if the enlarging lens was infinitely thin, the maximum possible incident angle is 81.3 degrees.&nbsp; So the light source would have to be less than a millimeter in width.&nbsp; Neither of these are real world possibilities.</p><p><br /></p><p>In short, you deliberately and dishonestly proposed an impossible strawman.&nbsp; Given that, why should anyone trust any of your other claims?[/QUOTE]</p><p><br /></p>

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