Best affordable macro lens?
I have a Nikon camera. I don't care if its a nikon lens as long as it will fit the mount, like a sigma or tamron. My price range is about 500 dollars. I would like the lens to work on dx and fx cameras.
Best macro for what?
depends what you are shooting as to what you will need… 50mm - 105mm
and if you just want to shoot "close-up", then you could use close-up filters, bellows, reversing ring…
personally, i use a Tamron 90mm f/2.8 macro lens…
I use both the Nikkor AF-S 60 mm f/2.8 and Nikkor AF-S 105 mm f/2.8.
The reason for using two is that I use one when the camera is mounted on a copy stand (the 60 mm) and the 105 mm when I'm in the field and need a longer stand-off from the subject. Affordable is relative. Since I need both, they are by definition "affordable" and over the years have paid for themselves
Those two lenses are FX so you can use them on your DX cameras.
Here is a link to all the Nikkor lenses
Sigma, Tamron, and Tokina all make excellent lenses in their pro lines. Look for f/2.8 and you should be fine. On digital crop cameras, the 60mm gives about the same field of view as a 100mm on a 35mm camera. I have the Canon 60mm lens and the Sigma 105mm for my Canon dSLR. Both are excellent. The 60mm is very small and doubles as a nice portrait lens for head and shoulder work. The 105 lets me back away from smaller critters or when I need to get a shadow out of the way.
For cost, shop around when you are ready to buy and see who has the best deal. If you are very cost conscious, then buying used from KEH or eBay can save even more.
I'd like to suggest an alternative. For less than $200, you can get a Canon 500D Close-up filter with an adaptor ring to fit any Nikon lens- it turns your lens into an excellent macro without the cost and weight of a dedicated lens. I use it all the time and love it.
http://www.canon-reviews.com/reviews/canon-500d-close-up-lens