Oh, thanx everybody!
imtheguy, itīs not an option, since the only (perhaps) good thing is that I can return the lens.
I have to admit I donīt get the IQ and size IMO, that axl are talking about?
Not mentioning other relative words "distortion, vignetting or chromatic abberations" that Iīve come across when reading about the lenses.
Do you (anybody) have any more of such photos like rktīs
first picture (like how close a flower I can get?, how many details of a flower, etc...?)?
So far I have been taking quite many flower-pictures and perhaps it would be easier to see the difference(s) between the 1:2 and 1:1...
Okey, I am now more in to take photos of flowers, leafs etc than insects.
BTW, your explanation, Marc Sabatella, was really good as well. Did finally get it.
How much differences is there between 100mm and 90mm (since I think the Sigma 105mm is too heavy for me) when thinking of the focal length?
Does it matter that the min focal for tamron (29cm) and pentax (30cm) is different (when concidering the 90mm-100mm)?