By first inspection this lens lives up to the expectation. It is lighweight for what it does; it doesn't really weight significantly more than the FA 120/4 macro. It is also very well made. No wobbly elements or rattles. It has metal filter threads and whole thing seem very solid. I'm surprised how bright and clear the viewfinder image is. It is brighter than the MZ-S finder when using the FA 200/4 macro; a lens that is one stop faster. The MZ-S has among the brighter finders of all Pentax 35mm slr's but it is no match for the 645 viewfinder. The angle of view seem identical between the said 200mm macro lens and the 150-300 zoom when the latter is set at 300mm. AF also work remarkably fast and precise in spite of this being an F:5.6 lens. I have high hopes for its optical qualities. After all, this is the focal lenght range where zoom seems to be easiest to design. I have yet to hear about an ED zoom lens in the telephoto range that wasn't great. The lens is assembled in Vietnam which probably explains its attractive price.
Included in the box was a "Asahi Pentax" S82 close up lens. There was no bill for it. I have enquired about Pentax close-up lernses so I guess it was included so that I could check it out. Anyway, it seems totally fantastic. Apart from the obvious conclusion that Pentax don't sell many of these close up lenses, as the lens is labeled Asahi and the manual was printed in 1978, it seems to work remarkably well. With this acessory the lens yield magnification at 300mm somewhere between 1:1 and 1:2 while maintaining a long working distance. Theres no light loss like with extension tubes. You can zoom and don't have to constantly refocus like when using extension with zooms. It also weight and cost a fraction of tubes and of course you also maintain AF and exact finder readout and focal lenght data imprinting. I cannot judge optical quality yet as I haven't shot anything. The urban legend says that close-up lenses may have not that great edge sharpness, but viewed from the viewfinder the image is sharp from edge to edge with this lens. If there is a loss of sharpness at the edges, which there probably is, it possibly not significant and it equally possibly fixable by stopping down. I don't see much point in keeping my 120/4 macrro. It weights about the same as the zoom. It doesn't provide significantly more max magnification. It has a shorter working distance that scares away critters and make camera placement more critical. It has almost certainly worse bokeh (well, the zoom cannot really have worse bokeh than the 120 Macro!). And it is not anyway near as versatile. Although the 120 macro is a fantastically sharp lens, I guess it won't be used much anymore. P�l
