http://www.thephotoforum.com/forum/photography-equipment-products/360517-best-macro-lens-any-brand.html#post3239641
Here is the third of my four very-first-ever test frames using the Nikon 6-T reverse-mounted on the front of the old, Nikon 100-300mm f/5.6 Ai-S manual focus lens. Shot outdoors on my patio, hand-held with the lens wide-open, at f/5.6 at 1/200 second. There's not much depth of field, so I leaned forward and backwards and when I saw the weird little "lines" on the side of the paint brush bristles, I fired. This brush is 1/2 almost to the millimeter, one full inch across the widest spot at the tips of the bristles. I got the idea from this lens review: Zoom Lenses For Nikon 'F' Mount: Telephoto

"The real surprise of the 100-300, however, comes when you put a close-up lens onto its front threads. I employed my standard Nikon 6T (reverse-mounted) and was absolutely floored by the high quality close-ups produced by this combination. High image sharpness and contrast, perfectly flat field, and virtually no CA are features you associate with an expensive Micro-Nikkor, not a makeshift combination of a achromatic attachment and a consumer zoom lens. Food for some real thoughts."