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<p>[QUOTE=&quot;dougsmit, post: 4400789, member: 19463&quot;]A recent post on the &#039;Game&#039; thread saw me show a denarius of Septimius Severus that I thought had a lot of detail on the reverse figure. </p><p><img src="https://www.cointalk.com/attachments/rj4520bb0235-jpg.1104787/" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></p><p><br /></p><p>Being a tad bored today, I got out some &#039;toys&#039; I had not used for a long time and tried to look at the reverse figure a bit more closely.&nbsp; The toy was the 50mm f/1.4 Super Takumar normal lens that came on my very first &#039;serious&#039; camera back in 1964.&nbsp; It was a good lens by 1964 standards but designed by people with pencils rather than computers.&nbsp; Because it was corrected to take sharp photos at long distances, I mounted it in reverse so the corrections would be better at a very close distance.&nbsp; </p><p>This is the first shot made with that rig.&nbsp; It is a set of eight images, each with slightly different focus, combined with a freeware program I have used for many years CombineZ.&nbsp; The program evaluates each part of each images and uses the sharpest part of each in one composite image.&nbsp; Usually I use this for shots of coins tilted to show the edge and face of the coin but it can be useful for super macro.&nbsp; The lens was set to marked f/5.6 but the effective aperture was much smaller since the image was so far past 1:1.&nbsp; In the old days, I had to calculate and compensate for the exposure but the through the lens metering on current cameras make this a skill for dinosaurs.&nbsp; What I did have to decide was to use f/5.6 since I feared any smaller setting would degrade sharpness due to diffusion (an optical &#039;law&#039; that can not be corrected out of lenses).&nbsp; Focus stacking allows creation of an image with the depth of field of a smaller aperture but the diffraction limits of a wider one.&nbsp; I will continue to play.&nbsp; Suggestions for subjects appreciated.</p><p>[ATTACH=full]1106060[/ATTACH][/QUOTE]</p><p><br /></p>

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