Presently, I own a Tamron 90mm macro. I love the lens and got it used at a great price. But, the reach is sometimes just not there. My lens of choice if I had the money would be a Sigma 150 or 180. But, I don't have the bucks, and choose to live with this otherwise great lens. I am considering increasing the reach of the tammy by adding a TC, either a 1.4 or 1.7. I think the 2X would possibly just degrade the image too much. When I have more money (after paying off some debts), I'll sell the tammy combo to my sister and buy the Sigma. My question is...... Do any of you have experience with coupling a tammy with a TC? If so, how does it affect bokah? If so, which TC magnification? If so, have any pics to post? If so, would a Kenko be good? If so, does a Kenko work on other lenses, as well? I'm just so confused about what to buy and whether it would be worth it or not. I guess I should have said "My questions are....." :tongue: Thanks.