Originally posted by yoon395 Hello, everyone
I'm still fairly a beginner but have been building experience using a Pentax K-x with a 18-55mm kit lens. In the somewhat near future I'm looking to upgrade to a nicer macro lens but I'm clueless in regards to several things:
1) Is a nicer macro lens all about lens speed (the max aperture) or are there other factors involved?
2) I don't know how ranges are classified, but I would primarily be taking macro shots, portraits, or full body shots (not much at a great distance). Is there something that could be a noticeable upgrade from the kit lens?
I've heard good things about the DA 40mm but it's a little steep for me. Any alternatives?
Any input appreciated, thanks!
I haven't read any of the replies so if this is repeatative, consider it a second on whatever was said.
First and foremost, you need to learn what Macro Is. There is nothing about your kit lens that could be considered a macro lens. A macro lens will allow you to reproduce 1:1 (or 1:2) typically. What that means is that the image on your sensor/film plane will be the same size (or half in the case of 1:2) as it is in real life.
Just to pull some numbers out of thin air (I know these aren't accurate, just for discussion sake), let us assume the sensor size is 1 inch square. That's 1 inch wide, 1 inch tall. If you were to take a photo of a coin that is 1 inch in diameter, at 1:1, the image would fill the frame (except the corners because the coin is round). If you were to take a photo at 1:2. it would fill roughly Half the frame. 1:4, one fourth of the frame and so on and that is about where your kit lens lies in the grand scheme of closeup. With a bellows, extension tubes, reversing lenses, mounting front to front, etc you can actually go larger than 1:1.
There are some macro masters around here that take drop dead gorgeous photos with their cobbled together setups. Then there are the rest of us who purchase dedicated macro lenses. These lenses are usually silly sharp and usually pretty expensive. They also make good telephoto lenses (most are in the 100mm range commonly). Pentax offers a few options. The DA35mm Limited is a normal lens that is capable of doing 1:1 macro. You really can't go wrong with this lens but to do 1:1 magnification, you are practically resting the lens front on your subject. This one would be nicely suited to a full body shot (but would not be macro at that point). Then there is a DFA50 f2.8. If I'm not mistaken, this is a 1:2 macro lens. Usable as a regular 50mm and could be suitable as a portrait lens or for full body shots. Then there is my favorite, the DFA100mm f2.8 WR. Great for portraits, as a 100mm telephoto, and shines nicely as a macro lens.
Other manufacturers also offer macro lenses, Tamron makes a very nice 90mm and sigma, a 105mm. I think they both have shorter range lenses as well but those two are 1:1 macro. Lenses that claim to have macro capability (all in one zooms) could be considered more Closeup capability rather than macro. Still usable to get up close and personal but not what I would call 'macro'.
Edit: If you want to get a DA40, go for it. By all accounts it's one of the fastest focusing and sharpest of the Pentax lineup. I don't have one because I cannot get past it's lack of bulk (and really don't need another lens in that range). But, it is not a macro lens.