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<blockquote data-quote="Eyelight" data-source="post: 363194" data-attributes="member: 24753">Dragonfly 3&quot; framed in camera at a 6&quot; subject size3.30&quot; DOF - 200mm, f/16 @ 94&quot; distance yields roughly 10&quot; image cropped to 6&quot; final image 3.05&quot; DOF - 200mm, f/22 @ 77&quot; distance yields roughly 8&quot; image size cropped to 6&quot; final image3.05&quot; DOF - 300mm, f/22 @ 115&quot; distance yields roughly 8&quot; image size cropped to 6&quot;final image3.54&quot; DOF - 300mm, f/45 @ 89&quot; distance yields roughly 6&quot; image size While&nbsp; 200mm is probably cleaner than 300mm and f/16 is probably cleaner than&nbsp; f/22, all have to be cropped except for the 300mm @ f/45, which likely&nbsp; is not the crispy one.&nbsp; Bear in mind that the DOFs above are considered&nbsp; where the acceptable sharpness ends based on viewing criteria that may&nbsp; or may not suit the final image.&nbsp; Also, the DOF is spread in front and&nbsp; behind the focus distance, so for these to work, the focus has to be&nbsp; selected with care.But then, where's the shutter speed and ISO&nbsp; been while we were maximizing the DOF.&nbsp; Either one or both have been&nbsp; going in the wrong direction for sharp&nbsp; images. So, this answer is not so much an answer as it is an exercise in why there is no single answer.&nbsp; Would&nbsp; diffraction be noticeable in any of these shots?&nbsp; Seems more likely&nbsp; that a slower shutter speed or higher ISO would have greater impact. In&nbsp; a way, the dragonfly question lends to Wayne's point because using an&nbsp; aperture less than f/16 pushes the subject even farther away to keep the&nbsp; DOF above 3&quot;.&nbsp; To use f/11 we need to move back to roughly 14' and end&nbsp; up with a 12&quot; image that has to be cropped to half the horizontal&nbsp; resolution. However, it could yield the best final image.... maybe.</blockquote>

[QUOTE="Eyelight, post: 363194, member: 24753"] Dragonfly 3" framed in camera at a 6" subject size 3.30" DOF - 200mm, f/16 @ 94" distance yields roughly 10" image cropped to 6" final image 3.05" DOF - 200mm, f/22 @ 77" distance yields roughly 8" image size cropped to 6" final image 3.05" DOF - 300mm, f/22 @ 115" distance yields roughly 8" image size cropped to 6"final image 3.54" DOF - 300mm, f/45 @ 89" distance yields roughly 6" image size While 200mm is probably cleaner than 300mm and f/16 is probably cleaner than f/22, all have to be cropped except for the 300mm @ f/45, which likely is not the crispy one. Bear in mind that the DOFs above are considered where the acceptable sharpness ends based on viewing criteria that may or may not suit the final image. Also, the DOF is spread in front and behind the focus distance, so for these to work, the focus has to be selected with care. But then, where's the shutter speed and ISO been while we were maximizing the DOF. Either one or both have been going in the wrong direction for sharp images. So, this answer is not so much an answer as it is an exercise in why there is no single answer. Would diffraction be noticeable in any of these shots? Seems more likely that a slower shutter speed or higher ISO would have greater impact. In a way, the dragonfly question lends to Wayne's point because using an aperture less than f/16 pushes the subject even farther away to keep the DOF above 3". To use f/11 we need to move back to roughly 14' and end up with a 12" image that has to be cropped to half the horizontal resolution. However, it could yield the best final image.... maybe. [/QUOTE]

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