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<blockquote data-quote="WayneF" data-source="post: 208994" data-attributes="member: 12496">The 28-105 is not a true micro lens. The micro would focus closer, but the 28-105 does come close.For example, the 35mm f/1.8&nbsp; lens focuses close enough that its largest reproduction ratio is 1:6.25&nbsp;&nbsp; (1/6 the size on the sensor than in real life)The 28-105mm focuses close enough that its largest reproduction ratio is 1:2 (image is 1/2 the size as the original.)A real regular micro lens will focus to 1:1, (image is same the size as the original.)Photograph a penny up close as possible.&nbsp; A penny is 3/4 inch diameter.The images of the penny are:35 mm - 1/8 inch diameter28-2105 - 3/8 inchreal micro lens - 3/4 inchThis&nbsp; is size on the senor, which is easier to imagine as film... the size on the negative.&nbsp; Digital is same thing, we just cannot take it out and look at it.1:2 from the 28-105 should be sufficient for your use.&nbsp;&nbsp; You speak of objects much larger than a penny.&nbsp;&nbsp; A letter size piece of paper (document) cannot be reproduced at 1:1 size.&nbsp;&nbsp; For DX, more like 1:9 is all that would be possible.&nbsp; The 35mm lens could do that, it should be sufficient too.The 28-105 could do as much as 1:2 (half size of a tiny subject). But you cannot use that much for a larger object.</blockquote>

[QUOTE="WayneF, post: 208994, member: 12496"] The 28-105 is not a true micro lens. The micro would focus closer, but the 28-105 does come close. For example, the 35mm f/1.8 lens focuses close enough that its largest reproduction ratio is 1:6.25 (1/6 the size on the sensor than in real life) The 28-105mm focuses close enough that its largest reproduction ratio is 1:2 (image is 1/2 the size as the original.) A real regular micro lens will focus to 1:1, (image is same the size as the original.) Photograph a penny up close as possible. A penny is 3/4 inch diameter. The images of the penny are: 35 mm - 1/8 inch diameter 28-2105 - 3/8 inch real micro lens - 3/4 inch This is size on the senor, which is easier to imagine as film... the size on the negative. Digital is same thing, we just cannot take it out and look at it. 1:2 from the 28-105 should be sufficient for your use. You speak of objects much larger than a penny. A letter size piece of paper (document) cannot be reproduced at 1:1 size. For DX, more like 1:9 is all that would be possible. The 35mm lens could do that, it should be sufficient too. The 28-105 could do as much as 1:2 (half size of a tiny subject). But you cannot use that much for a larger object. [/QUOTE]

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