To buy or not to buy....

that is the question.

I am really interested in getting into the macro side of photography and am not sure if I need to go ahead and purchase a dedicated macro lens (most likely either a 100mm or 105mm).

Am I better off just using my extension tubes on both the 50mm & 85mm that I currently have? Would I be better off selling the 85mm and getting the Canon 100mm macro instead since it wouldn't make sense to have both the 85 & 100mm as they are so close in focal length to each other?

I will be keeping the extension tubes no matter what as they can only enhance whichever lens(s) I end up using, correct?

Appreciate any and all feedback.

I'd try the tubes with the 85mm and see how you like it first. I have two macro lenses, but I also have Kenko tubes and use them quite a bot with a variety of lenses.

I guess a lot fo the answer will be dependant on what you want to shoot.

Are you in need for 1:1 or are you looking for a smaller ratio? or a greater ratio?

While I agree with Nightcat about the focal lengths being similar, but with the full set of kenkos would get less than 1:1 whereas a 90-105 dedicated macro with a full set of tubes will afford you approx 2:1 magnification. So if your shots need the magnification, the 85 + tubes may be less of a way to approximate your future experience.

With that said however, the 50mm with a full set of tubes gets to 1:1 and if you really want to experiment you can use your 10-20 and/or 17-50 to get even higher magnifications! (there was a small thread about using wide angle macro shots....interesting to goof off with for sure!)

You are correct: people use the kenkos with all sorts of lenses - including (and especially?) with dedicated macros - so you will not be wasting your money if later on you decide on getting a dedicated macro after the tubes.

Just my 2cents

Well I ended up buying a Tamron 90mm f/2.8 macro instead. Got it for under $300 used. Will post some pics once I get it hopefully later this week.

Thanks for all the help everyone.

congrats on the purchase and good luck! post later when you get the lens!