Which macro lens?

I am looking to buy a new macro lens, I have a Pentax K10 also i have a sigma 70-300 which has a macro facility on it but you have to be quite a long way away from the subject and I prefer to get closer to the subject.
I was thinking of the Pentax 100mm F2.8 SMC D FA Marco or the 50mm version. I wonder if the 100mm is worth the extra £50?!
Any help greatly received!! (or better recomandations) Thank you

I would def go for the 100mm version of whichever macro lens you decide on as if you are doing insects you need that extra reach.
I would say either the Pentax, Tamron 90mm or Sigma 105mm will all do you just as well tbh.
I use both a Tamron 90mm and an old Vivitar 100mm manual focus lens and prefer the Vivitar for quality but the Tamron for portability.
The Vivitar is made completely of metal and is just so ruddy heavy.

There have been a few recent recommendations on the forums...
Personally, if you're not 100% stuck on Pentax, I'd suggest you also look at Tamron's 90mm f2.8 DI Macro lens. I got it for several hundred dollars less than the Pentax 100mm.
Absolutely beautiful results. (I have been used to closeups from "macro enabled" zoom lenses... just no comparison.)
No regrets whatsoever.

I like the super thin DOF and/or staying some distance from subjects that the 100mm allows.

I've used the 50 and the 100 pentax.
if all you want is coins and jelwery, the 50 is fine.
for live subjects, you'll need/want the extra working distance of the 100.

I use my 100 primarily for portraits, but there's lots of samples of macro stuff by me and others posted.

ps, here's a test shot of my step daughter, and her bf I did for practice the other day...
It is one hell of a fine portrait lens!




also, I know not the best portrait, just they stood in while i was setting up for another couple......the other guy had hair so no brightspot on bald head....

I too have the Pentax 100mm (the older "SMC-F" brute). Optically the same as all the other Pentax 100mm, AFAIK, and brutally sharp for portraiture
Astonishingly so
Matt

The Cosina/Vivitar 100mm f/3.5 macro is plastic, small and light so I can easily carry it wherever I go. Optical quality is way beyond expectations. Does 1:2 or 1:1 with included adapter. Inexpensive... around €100.





The Vivitar Series 1 105mm f/2.5 macro is heralded as perhaps the sharpest 1:1 macro ever. Bigger and heavier than the above, so I own both. Cost me less than €250 and gets me bugs like this:

I have the Cosina 3.5 100mm as well under the Phoenix brand.
Bought it off Ebay as autofocus and when I received it the lens was manual.
Too expensive to return it as it was from the USA but its actually not that bad for the money.

This was a quick shot taken with it, only time it has been used.

Thanks for your comments .......your garden bug is a vine weavel by the way....garden pest!!!!

Aha! The black vine weevil. Thanks for the ident.