Originally posted by Omestes Not to seem like a troll, but why do you say 1:2 is superior? In my life, having a 1:1 macro is a necessity.
Ahoy!
I entirely agree about true 1:1 macro lenses. I own the Tamron 272E and have owned many other 1:1 and 1:2 macro's, but my reference was specifically with respect to the Cosina AF 100/3.5 MC macro as it's native 1:2 is vastly superior compared to it with the 1:1 adapter fitted as it doesn't always focus correctly and it softens towards the outer edge of the image. I have some beautiful images taken using it in 1:2 mode in addition to those with the Tamron 272E on the interweb, and they compare with each other pretty much identically, though the Cosina (or any of it's variants) costs a fraction of any true 1:1 macro, and for the price, it's one of photography's gem lenses in terms of price and IQ. I love the Cosina simply because of what it is. I don't think there's anything that can match it like for like and it's just insane that K-Mount owners are prepared to pay ridiculous money for the Pentax version which is the exact same lens (it's madness)!
The supplied 1:1 adapter lens is a total POS and superior +1, +2 or higher magnification adapter lenses can be bought from Amazon for not a lot of money, but I'll stand by my comment that it performs best in native 1:2 mode, and even if images from it were put alongside true 1:1 macro lens examples, I don't think most people would be able to tell the difference. The 'plastic fantastic' is just a gem of a lens optically, and I've owned about 5x copies of it over the years in addition to 50/3.5 1:2, 50/2.8 1:1, 105/2.8 1:1 and 90/2.8 1:1, so have a fair amount of personal experience with various makes/models, so I wasn't saying 1:2 is better than 1:1, just that the Cosina provides optimum IQ without the 1:1 adapter in native 1:2 mode.
Hope that clears up any misunderstanding.